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Sample records for female fertility asexual

  1. speciation through asexuality in fish: postzygotic reproductive isolation may be completed in spite of fertility of hybrids

    Directory of Open Access Journals (Sweden)

    Karel Janko

    2015-12-01

    Altogether, it appears that initiation of hybrid asexuality and the completion of speciation process through formation of postRIMs are interconnected phenomena. Both processes are linked to the genetic divergence of hybridizing taxa: initially, hybridization between little diverged species leads to recombinant and fertile hybrids allowing intensive gene flow. As the hybridizing taxa continue to diverge, clonally reproducing hybrid females and sterile males become dominant and the gene flow ceases. The speciation may therefore be completed through asexuality of hybrids The work was supported by grant no. 13-12580S provided by the Czech Science Foundation (www.gacr.cz. Further support was provided by the Academy of Sciences of the Czech Republic (www.cas.cz by the grant no. RVO 67985904

  2. Asexual reproduction induces a rapid and permanent loss of sexual reproduction capacity in the rice fungal pathogen Magnaporthe oryzae: results of in vitro experimental evolution assays

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    Saleh Dounia

    2012-03-01

    Full Text Available Abstract Background Sexual reproduction is common in eukaryotic microorganisms, with few species reproducing exclusively asexually. However, in some organisms, such as fungi, asexual reproduction alternates with episodic sexual reproduction events. Fungi are thus appropriate organisms for studies of the reasons for the selection of sexuality or clonality and of the mechanisms underlying this selection. Magnaporthe oryzae, an Ascomycete causing blast disease on rice, reproduces mostly asexually in natura. Sexual reproduction is possible in vitro and requires (i two strains of opposite mating types including (ii at least one female-fertile strain (i.e. a strain able to produce perithecia, the female organs in which meiosis occurs. Female-fertile strains are found only in limited areas of Asia, in which evidence for contemporary recombination has recently been obtained. We induced the forced evolution of four Chinese female-fertile strains in vitro by the weekly transfer of asexual spores (conidia between Petri dishes. We aimed to determine whether female fertility was rapidly lost in the absence of sexual reproduction and whether this loss was controlled genetically or epigenetically. Results All the strains became female-sterile after 10 to 19 rounds of selection under asexual conditions. As no single-spore isolation was carried out, the observed decrease in the production of perithecia reflected the emergence and the invasion of female-sterile mutants. The female-sterile phenotype segregated in the offspring of crosses between female-sterile evolved strains and female-fertile wild-type strains. This segregation was maintained in the second generation in backcrosses. Female-sterile evolved strains were subjected to several stresses, but none induced the restoration of female fertility. This loss of fertility was therefore probably due to genetic rather than epigenetic mechanisms. In competition experiments, female-sterile mutants produced similar

  3. Differential evolution of asexual and sexual females in a benign culture environment

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    Snell, Terry W.

    2013-01-01

    Here we report one of the first investigations of evolvability of lifespan and reproduction in metazoans, examining both extrinsic and intrinsic factors. We tested effects on senescence of an environmental variable (simulated lake hydroperiod, the length of time an aquatic habitat is inundated), female reproductive physiology (asexual females that reproduce by ameiosis, versus sexual females reproducing by meiosis), and time in a benign culture environment (minimal, if any, external mortality factors). To do this we established chemostat cultures of the rotifer Brachionus plicatilis s.s., and maintained the cultures for 385 d. Hydroperiod alone or in interaction with the effects of time in the benign environment (season) or reproductive physiology had no significant effect on the net reproductive rate, generation time, or rate of aging. Yet combining animals from both ephemeral and permanent hydroperiods revealed a 26% increase in asexual female lifespan across seasons (23% decrease in the rate of aging) and a 56% increase in asexual fecundity, suggesting that maintenance in benign laboratory conditions leads to slower aging. The relative stasis of traits for sexual females implies an impact of reproductive physiology on evolvability. In addition we found a positive correlation between fecundity and lifespan, suggesting an absence of trade-offs in life history traits in the benign laboratory environment. PMID:24795527

  4. A Comparison of In Vitro and In Vivo Asexual Embryogenesis

    NARCIS (Netherlands)

    Hand, Melanie; Vries, de S.C.; Koltunow, Anna

    2016-01-01

    In plants, embryogenesis generally occurs through the sexual process of double fertilization, which involves a haploid sperm cell fusing with a haploid egg cell to ultimately give rise to a diploid embryo. Embryogenesis can also occur asexually in the absence of fertilization, both in vitro and in

  5. Sexual versus Asexual Reproduction: Distinct Outcomes in Relative Abundance of Parthenogenetic Mealybugs following Recent Colonization.

    Science.gov (United States)

    Tabata, Jun; Ichiki, Ryoko T; Tanaka, Hirotaka; Kageyama, Daisuke

    2016-01-01

    Asexual reproduction, including parthenogenesis in which embryos develop within a female without fertilization, is assumed to confer advantages over sexual reproduction, which includes a "cost of males." Sexual reproduction largely predominates in animals, however, indicating that this cost is outweighed by the genetic and/or ecological benefits of sexuality, including the acquisition of advantageous mutations occurring in different individuals and the elimination of deleterious mutations. But the evolution of sexual reproduction remains unclear, because we have limited examples that demonstrate the relative success of sexual lineages in the face of competition from asexual lineages in the same environment. Here we investigated a sympatric occurrence of sexual and asexual reproduction in the pineapple mealybug, Dysmicoccus brevipes. This pest invaded southwestern Japan, including Okinawa and Ishigaki Islands, in the 1930s in association with imported pineapple plants. Our recent censuses demonstrated that on Okinawa sexually reproducing individuals can coexist with and even dominate asexual individuals in the presence of habitat and resource competition, which is considered to be severe for this nearly immobile insect. Molecular phylogeny based on partial DNA sequences in the mitochondrial and nuclear genomes, as well as the endosymbiotic bacterial genome, revealed that the asexual lineage diverged from a common sexual ancestor in the relatively recent past. In contrast, only the asexual lineage exhibiting obligate apomictic thelytoky was discovered on Ishigaki. Co-existence of the two lineages cannot be explained by the results of laboratory experiments, which showed that the intrinsic rate of increase in the sexual lineage was not obviously superior to that of the asexual lineage. Differences in biotic and/or abiotic selective forces operating on the two islands might be the cause of this discrepancy. This biological system offers a unique opportunity to assess

  6. Sexual conflict and the evolution of asexuality at low population densities.

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    Gerber, Nina; Kokko, Hanna

    2016-10-26

    Theories for the evolution of sex rarely include facultatively sexual reproduction. Sexual harassment by males is an underappreciated factor: it should at first sight increase the relative advantage of asexual reproduction by increasing the cost of sex. However, if the same females can perform either sexual or asexual life cycles, then females trying to reproduce asexually may not escape harassment. If resisting male harassment is costly, it might be beneficial for a female to accept a mating and undertake a sexual life cycle rather than 'insist' on an asexual one. We investigate the effects of sexual harassment on the maintenance of sex under different population densities. Our model shows that resisting matings pays off at low population densities, which leads to the complete extinction of males, and thus to the evolution of completely asexual populations. Facultative sex persists in a narrow range of slightly higher densities. At high densities, selection favours giving up resisting male mating attempts and thus sexual reproduction takes over. These interactions between the outcomes of sexual conflict and population density suggest an explanation for the rarity of facultative sex and also patterns of geographical parthenogenesis, where marginal environments with potentially low densities are associated with asexuality. © 2016 The Author(s).

  7. Fertility in female childhood cancer survivors

    DEFF Research Database (Denmark)

    De Bruin, Marie L; Van Dulmen-den Broeder, Eline; Van den Berg, Marleen H

    2009-01-01

    chemotherapy and radiotherapy may have an adverse effect on ovarian function, ovarian reserve and uterine function, clinically leading to sub-fertility, infertility, premature menopause and/or adverse pregnancy outcomes. Here we will first address normal female fertility and methods to detect decreased...... fertility. Hence we will focus on direct effects as well as late fertility-related adverse effects caused by chemotherapy and radiotherapy, and we will conclude with a summary of current options for fertility preservation in female childhood cancer survivors.......Advances in childhood cancer treatment over the past decades have significantly improved survival, resulting in a rapidly enlarging group of childhood cancer survivors. There is much concern, however, about the effects of treatment on reproductive potential. In women there is evidence that both...

  8. Female employment reduces fertility in rural Senegal.

    Science.gov (United States)

    Van den Broeck, Goedele; Maertens, Miet

    2015-01-01

    Economic growth and modernization of society are generally associated with fertility rate decreases but which forces trigger this is unclear. In this paper we assess how fertility changes with increased labor market participation of women in rural Senegal. Evidence from high-income countries suggests that higher female employment rates lead to reduced fertility rates but evidence from developing countries at an early stage of demographic transition is largely absent. We concentrate on a rural area in northern Senegal where a recent boom in horticultural exports has been associated with a sudden increase in female off-farm employment. Using survey data we show that employed women have a significantly higher age at marriage and at first childbirth, and significantly fewer children. As causal identification strategy we use instrumental variable and difference-in-differences estimations, combined with propensity score matching. We find that female employment reduces the number of children per woman by 25%, and that this fertility-reducing effect is as large for poor as for non-poor women and larger for illiterate than for literate women. Results imply that female employment is a strong instrument for empowering rural women, reducing fertility rates and accelerating the demographic transition in poor countries. The effectiveness of family planning programs can increase if targeted to areas where female employment is increasing or to female employees directly because of a higher likelihood to reach women with low-fertility preferences. Our results show that changes in fertility preferences not necessarily result from a cultural evolution but can also be driven by sudden and individual changes in economic opportunities.

  9. Female employment reduces fertility in rural Senegal.

    Directory of Open Access Journals (Sweden)

    Goedele Van den Broeck

    Full Text Available Economic growth and modernization of society are generally associated with fertility rate decreases but which forces trigger this is unclear. In this paper we assess how fertility changes with increased labor market participation of women in rural Senegal. Evidence from high-income countries suggests that higher female employment rates lead to reduced fertility rates but evidence from developing countries at an early stage of demographic transition is largely absent. We concentrate on a rural area in northern Senegal where a recent boom in horticultural exports has been associated with a sudden increase in female off-farm employment. Using survey data we show that employed women have a significantly higher age at marriage and at first childbirth, and significantly fewer children. As causal identification strategy we use instrumental variable and difference-in-differences estimations, combined with propensity score matching. We find that female employment reduces the number of children per woman by 25%, and that this fertility-reducing effect is as large for poor as for non-poor women and larger for illiterate than for literate women. Results imply that female employment is a strong instrument for empowering rural women, reducing fertility rates and accelerating the demographic transition in poor countries. The effectiveness of family planning programs can increase if targeted to areas where female employment is increasing or to female employees directly because of a higher likelihood to reach women with low-fertility preferences. Our results show that changes in fertility preferences not necessarily result from a cultural evolution but can also be driven by sudden and individual changes in economic opportunities.

  10. Female fertility preservation in the pediatric and adolescent cancer patient population.

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    Algarroba, Gabriela N; Sanfilippo, Joseph S; Valli-Pulaski, Hanna

    2018-04-01

    The 5-year survival rate for childhood cancer is over 80%, thereby increasing the number of young women facing infertility in the future because of the gonadotoxic effects of chemotherapy and radiation. The gonadotoxic effects of childhood cancer treatment vary by the radiation regimen and the chemotherapeutic drugs utilized. Although the American Society of Clinical Oncology guidelines recommend fertility preservation for all patients, there are several barriers and ethical considerations to fertility preservation in the pediatric and adolescent female population. Additionally, the fertility preservation methods for pre- and postpubertal females differ, with only experimental methods available for prepubertal females. We will review the risk of chemotherapy and radiation on female fertility, the approach to fertility preservation in the pediatric and adolescent female population, methods of fertility preservation for both pre- and postpubertal females, barriers to fertility preservation, cost, and psychological and ethical considerations. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Female relative wages, household specialization and fertility

    OpenAIRE

    Siegel, Christian

    2017-01-01

    Falling fertility rates have often been linked to rising female wages. However, over the last 40 years the US total fertility rate has been rather stable while female wages have continued to grow. Over the same period, women's hours spent on housework have declined, but men's have increased. I propose a model in which households are not perfectly specialized, but both men and women contribute to home production. As the gender wage gap narrows, the time allocations of men and women converge, a...

  12. Postmating sexual conflict and female control over fertilization during gamete interaction.

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    Firman, Renée C

    2018-06-01

    Males and females rarely have identical evolutionary interests over reproduction, and when the fitness of both sexes is dependent upon paternity outcomes, sexual conflict over fertilization is inevitable. In internal fertilizers, the female tract is a formidable selective force on the number and integrity of sperm that reach the egg. Selection on sperm quality is intensified when females mate multiply and rival males are forced to compete for fertilizations. While male adaptations to sperm competition have been well documented (e.g., increased sperm fertilizing capacity), much less attention has been given to the evolutionary consequences of postmating sexual conflict for egg form and function. Specifically, increased sperm competitiveness can be detrimental by giving rise to an elevation in reproductive failure resulting from polyspermy. Spanning literature on both internal and external fertilizers, in this review I discuss how females respond to sperm competition via fertilization barriers that mediate sperm entry. These findings, which align directly with sexual conflict theory, indicate that females have greater control over fertilization than has previously been appreciated. I then consider the implications of gametic sexual conflict in relation to the development of reproductive isolation and speculate on potential mechanisms accounting for "egg defensiveness." Finally, I discuss the functional significance of egg defensiveness for both the sexes, and sperm selection for females. © 2018 New York Academy of Sciences.

  13. Jobs and kids: Female employment and fertility in China

    OpenAIRE

    Fang, Hai; Eggleston, Karen N.; Rizzo, John A.; Zeckhauser, Richard J.

    2013-01-01

    Data on 2,355 married women from the 2006 China Health and Nutrition Survey are used to study how female employment affects fertility in China. China has deep concerns with both population size and female employment, so the relationship between the two should be better understood. Causality flows in both directions. A conceptual model shows how employment prospects affect fertility. Then a well-validated instrumental variable isolates this effect. Female employment reduces a married woman’s...

  14. Does the silver moss Bryum argenteum exhibit sex-specific patterns in vegetative growth rate, asexual fitness or prezygotic reproductive investment?

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    Horsley, Kimberly; Stark, Lloyd R; McLetchie, D Nicholas

    2011-05-01

    Expected life history trade-offs associated with sex differences in reproductive investment are often undetected in seed plants, with the difficulty arising from logistical issues of conducting controlled experiments. By controlling genotype, age and resource status of individuals, a bryophyte was assessed for sex-specific and location-specific patterns of vegetative, asexual and sexual growth/reproduction across a regional scale. Twelve genotypes (six male, six female) of the dioecious bryophyte Bryum argenteum were subcultured to remove environmental effects, regenerated asexually to replicate each genotype 16 times, and grown over a period of 92 d. Plants were assessed for growth rates, asexual and sexual reproductive traits, and allocation to above- and below-ground regenerative biomass. The degree of sexual versus asexual reproductive investment appears to be under genetic control, with three distinct ecotypes found in this study. Protonemal growth rate was positively correlated with asexual reproduction and sexual reproduction, whereas asexual reproduction was negatively correlated (appeared to trade-off) with vegetative growth (shoot production). No sex-specific trade-offs were detected. Female sex-expressing shoots were longer than males, but the sexes did not differ in growth traits, asexual traits, sexual induction times, or above- and below-ground biomass. Males, however, had much higher rates of inflorescence production than females, which translated into a significantly higher (24x) prezygotic investment for males relative to females. Evidence for three distinct ecotypes is presented for a bryophyte based on regeneration traits. Prior to zygote production, the sexes of this bryophyte did not differ in vegetative growth traits but significantly differed in reproductive investment, with the latter differences potentially implicated in the strongly biased female sex ratio. The disparity between males and females for prezygotic reproductive investment is

  15. Fertility and Childbearing Among American Female Physicians.

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    Stentz, Natalie Clark; Griffith, Kent A; Perkins, Elena; Jones, Rochelle DeCastro; Jagsi, Reshma

    2016-10-01

    Female physicians may experience unique challenges regarding fertility and family planning. We sought to determine childbearing patterns and decision-making among American female physicians. In 2012-2013, we surveyed a random sample of 600 female physicians who graduated medical school between 1995 and 2000. Primary outcome measures included fertility and childbearing history, reflections regarding decision-making, perceptions of workplace support, and estimations of childbearing potential. Response rate was 54.5% (327/600). A majority (82.0%) of the sample were parents, 77.4% had biological children with an average of 2.3 children. Average age at medical school graduation was 27.5 years, at completion of training (completion of medical school, residency, and/or fellowship) was 31.6 years, and at first pregnancy was 30.4 years. Nearly one quarter (24.1%) of respondents who had attempted conception were diagnosed with infertility, with an average age at diagnosis of 33.7 years. Among those with infertility, 29.3% reported diminished ovarian reserve. When asked what they would do differently in retrospect, most respondents (56.8%) would do nothing differently regarding fertility/conception/childbearing, 28.6% would have attempted conception earlier, 17.1% would have gone into a different specialty, and 7.0% would have used cryopreservation to extend fertility. Fewer of those whose first pregnancy was in medical school perceived substantial workplace support (68.2%) than those whose first pregnancies followed training (88.6%). A substantial proportion of female physicians have faced infertility or have regrets about family planning decisions and career decision-making. Combining a medical career with motherhood continues to pose challenges, meriting further investigation and targeted support.

  16. Freedom, invisibility, and community: a qualitative study of self-identification with asexuality.

    Science.gov (United States)

    MacNeela, Pádraig; Murphy, Aisling

    2015-04-01

    A significant body of research is now emerging on the subjective meaning of asexuality. This study explored how self-identification as asexual is managed, both as a threat to the self-concept and a source of personal meaning. A total of 66 self-identified asexuals were recruited from an asexuality internet community and responded to open-ended questions on an online survey. Of these, 31 participants identified as female, 15 as male, 18 gave a different label such as genderqueer or androgynous, and two did not provide information on gender. A thematic analysis of the transcripts resulted in three themes. Socially, asexuality attracted denial and resistance due to incompatibility with heteronormative societal expectations. Despite the threat to self-integrity arising from asexuality being socially rejected, it was typically assimilated as a valued and meaningful orientation on an intra-personal level, aided by information and support from the online community. A second level of threat to self arose whereby other self-identifications, especially gender, had to be reconciled with a non-sexual persona. The accommodation made to other elements of the self was reflected in complex sub-identities. The findings were interpreted using identity process theory to understand how threats arising from self-identifying as asexual are managed. Although asexuality emerges as an orientation to sexuality that can be reconciled with the self, its invisibility or outright rejection in society constitute an on-going challenge.

  17. Fertility and sexual function in female Hodgkin lymphoma survivors of reproductive age.

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    Eeltink, Corien M; Incrocci, Luca; Witte, Birgit I; Meurs, Saskia; Visser, Otto; Huijgens, Peter; Verdonck-de Leeuw, Irma M

    2013-12-01

    To assess the perceived fertility status and to determine the association between perceived fertility status and sexual function, as reported by young female Hodgkin lymphoma survivors. Young female Hodgkin lymphoma survivors are at risk of infertility and impaired sexual function. However, little is known about their awareness of infertility and its association with sexual functioning. A descriptive questionnaire survey. In this cross-sectional study, a survey was completed by female Hodgkin lymphoma survivors (40 years). Outcome measures included self-reported fertility status and sexual problems and the internationally validated Female Sexual Function Index. In total, 36 survivors were included (mean age 32 years, SD 4). Eighteen women (50%) thought themselves fertile. Eight survivors (22%) who perceived themselves as being infertile were more often treated with alkylator-based chemotherapy, and 63% reported sexual dysfunction. Ten survivors (28%) were not aware as to whether they were fertile or not; seven of these would like to have children. The reported fertility status was related to age and chemotherapy regimen. Regarding sexuality, 14 (39%) of the female Hodgkin lymphoma survivors reported one or more sexual problem and none reported recovery. Female sexual dysfunction according to the Female Sexual Function Index was reported by 11 (31%) survivors. Almost 30% of Hodgkin lymphoma survivors do not know whether they are fertile or not. Overall sexual dysfunction is common in Hodgkin lymphoma survivors and comparable to the general population. However, a lack of desire was significantly more often reported in female Hodgkin lymphoma survivors. To prevent assumed infertility and unintended childlessness by postponing parenthood in young female survivors, awareness of fertility status is needed. There is also a need to routinely assess sexual function and provide adequate interventions to improve arousal and lubrication problems. © 2013 John Wiley & Sons Ltd.

  18. Sexual and asexual oogenesis require the expression of unique and shared sets of genes in the insect Acyrthosiphon pisum

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    Gallot Aurore

    2012-02-01

    Full Text Available Abstract Background Although sexual reproduction is dominant within eukaryotes, asexual reproduction is widespread and has evolved independently as a derived trait in almost all major taxa. How asexuality evolved in sexual organisms is unclear. Aphids, such as Acyrthosiphon pisum, alternate between asexual and sexual reproductive means, as the production of parthenogenetic viviparous females or sexual oviparous females and males varies in response to seasonal photoperiodism. Consequently, sexual and asexual development in aphids can be analyzed simultaneously in genetically identical individuals. Results We compared the transcriptomes of aphid embryos in the stages of development during which the trajectory of oogenesis is determined for producing sexual or asexual gametes. This study design aimed at identifying genes involved in the onset of the divergent mechanisms that result in the sexual or asexual phenotype. We detected 33 genes that were differentially transcribed in sexual and asexual embryos. Functional annotation by gene ontology (GO showed a biological signature of oogenesis, cell cycle regulation, epigenetic regulation and RNA maturation. In situ hybridizations demonstrated that 16 of the differentially-transcribed genes were specifically expressed in germ cells and/or oocytes of asexual and/or sexual ovaries, and therefore may contribute to aphid oogenesis. We categorized these 16 genes by their transcription patterns in the two types of ovaries; they were: i expressed during sexual and asexual oogenesis; ii expressed during sexual and asexual oogenesis but with different localizations; or iii expressed only during sexual or asexual oogenesis. Conclusions Our results show that asexual and sexual oogenesis in aphids share common genetic programs but diverge by adapting specificities in their respective gene expression profiles in germ cells and oocytes.

  19. Jobs and Kids: Female Employment and Fertility in Rural China

    OpenAIRE

    Hai Fang; Karen N. Eggleston; John A. Rizzo; Richard J. Zeckhauser

    2010-01-01

    Data on 2,355 married women from the 2006 China Health and Nutrition Survey are used to study how female employment affects fertility in China. China has deep concerns with both population size and female employment, so the relationship between the two should be better understood. Causality flows in both directions. A conceptual model shows how employment prospects affect fertility. Then a well-validated instrumental variable isolates this effect. Female employment reduces a married woman's p...

  20. Fertility Effects on Female Labor Supply

    DEFF Research Database (Denmark)

    Lundborg, Petter; Plug, Erik; Rasmussen, Astrid Würtz

    This paper introduces a new IV strategy based on IVF induced fertility variation in childless families to estimate the causal effect of having children on female labor supply using IVF treated women in Denmark. Because observed chances of IVF success do not depend on labor market histories, IVF...... treatment success provides a plausible instrument for childbearing. Our IV estimates indicate that fertility effects are: (a) negative, large and long lasting; (b) much stronger at the extensive margin than at the intensive margin, and (c) similar for mothers, not treated with IVF, which suggests that IVF...

  1. Male chimpanzees' grooming rates vary by female age, parity, and fertility status

    DEFF Research Database (Denmark)

    Proctor, Darby P; Lambeth, Susan P; Schapiro, Steve

    2011-01-01

    , should show little or no preference when choosing mating partners (e.g. should mate indiscriminately). To determine if the preferences indicated by copulations appear in other contexts as well as how they interact, we examined how male chimpanzees' grooming patterns varied amongst females. We found...... that males' preferences were based on interactions among females' fertility status, age, and parity. First, grooming increased with increasing female parity. We further found an effect of the estrous cycle on grooming; when females were at the lowest point of their cycle, males preferentially groomed parous...... females at peak reproductive age, but during maximal tumescence, males preferred the oldest multiparous females. Nulliparous females received relatively little grooming regardless of age or fertility. Thus, male chimpanzees apparently chose grooming partners based on both female's experience and fertility...

  2. Crybb2 deficiency impairs fertility in female mice

    International Nuclear Information System (INIS)

    Gao, Qian; Sun, Li-Li; Xiang, Fen-Fen; Gao, Li; Jia, Yin; Zhang, Jian-Rong; Tao, Hai-Bo; Zhang, Jun-Jie; Li, Wen-Jie

    2014-01-01

    Highlights: • Crybb2 deletion impaired female fertility. • Crybb2 deletion dramatically affected the production of reproduction-related hormones and hormone response. • Crybb2 deletion impaired follicular development and inhibited the proliferation of granulosa cells. • Crybb2 deletion promoted follicular atresia and apoptosis in granulosa cells. - Abstract: Beta-B2-crystallin (CRYBB2), encoded by Crybb2 gene, is a major protein in the mammalian eye lens that plays an important role in maintaining the transparency of the ocular lens. However, CRYBB2 also plays important roles in many extra-lenticular tissues and organs such as the retina, brain and testis. Our previous studies demonstrated that male Crybb2 deficient (Crybb2 −/− ) mice have reduced fertility compared with wild-type (WT) mice, while female Crybb2 −/− mice exhibited reduced ovary weights and shorter estrous cycle percentages. Here we specifically investigated the role of CRYBB2 in the female reproductive system. Our studies revealed that ovaries from female Crybb2 −/− mice exhibited significantly reduced numbers of primordial, secondary and pre-ovulatory follicles when compared with WT mice, while the rate of atretic follicles was also increased. Additionally, fewer eggs were collected from the oviduct of Crybb2 −/− female mice after superovulation. Estrogen levels were higher in the metestrus and diestrus cycles of female Crybb2 −/− mice, while progesterone levels were lower in diestrus cycles. Furthermore, the expression of survival and cell cycle genes, Bcl-2, Cdk4 and Ccnd2, were significantly decreased in granulosa cells isolated from female Crybb2 −/− mice, consistent with the predominant expression of CRYBB2 in ovarian granulosa cells. Our results reveal a critical role for CRYBB2 in female fertility and specific effects on the proliferation and survival status of ovarian granulosa cells

  3. Crybb2 deficiency impairs fertility in female mice

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Qian [Department of Laboratory Diagnosis, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China); Sun, Li-Li [Aviation Medical Evaluation and Training Center of Airforce in Dalian, Dalian, Liaoning Province 116013 (China); Department of Laboratory Diagnosis, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China); Xiang, Fen-Fen [Department of Laboratory Medicine, Putuo Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai 200062 (China); Gao, Li [Department of Pathology, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China); Jia, Yin; Zhang, Jian-Rong; Tao, Hai-Bo [Department of Laboratory Diagnosis, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China); Zhang, Jun-Jie, E-mail: zhangjj910@163.com [Department of Obstetrics and Gynecology, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China); Li, Wen-Jie, E-mail: wenjieli@pku.org.cn [Department of Laboratory Diagnosis, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China)

    2014-10-10

    Highlights: • Crybb2 deletion impaired female fertility. • Crybb2 deletion dramatically affected the production of reproduction-related hormones and hormone response. • Crybb2 deletion impaired follicular development and inhibited the proliferation of granulosa cells. • Crybb2 deletion promoted follicular atresia and apoptosis in granulosa cells. - Abstract: Beta-B2-crystallin (CRYBB2), encoded by Crybb2 gene, is a major protein in the mammalian eye lens that plays an important role in maintaining the transparency of the ocular lens. However, CRYBB2 also plays important roles in many extra-lenticular tissues and organs such as the retina, brain and testis. Our previous studies demonstrated that male Crybb2 deficient (Crybb2{sup −/−}) mice have reduced fertility compared with wild-type (WT) mice, while female Crybb2{sup −/−} mice exhibited reduced ovary weights and shorter estrous cycle percentages. Here we specifically investigated the role of CRYBB2 in the female reproductive system. Our studies revealed that ovaries from female Crybb2{sup −/−} mice exhibited significantly reduced numbers of primordial, secondary and pre-ovulatory follicles when compared with WT mice, while the rate of atretic follicles was also increased. Additionally, fewer eggs were collected from the oviduct of Crybb2{sup −/−} female mice after superovulation. Estrogen levels were higher in the metestrus and diestrus cycles of female Crybb2{sup −/−} mice, while progesterone levels were lower in diestrus cycles. Furthermore, the expression of survival and cell cycle genes, Bcl-2, Cdk4 and Ccnd2, were significantly decreased in granulosa cells isolated from female Crybb2{sup −/−} mice, consistent with the predominant expression of CRYBB2 in ovarian granulosa cells. Our results reveal a critical role for CRYBB2 in female fertility and specific effects on the proliferation and survival status of ovarian granulosa cells.

  4. Marginal distribution and high heterozygosity of asexual Caloglossa vieillardii (Delesseriaceae, Rhodophyta) along the Australian coasts.

    Science.gov (United States)

    Kamiya, Mitsunobu; Saba, Erika; West, John A

    2017-12-01

    In animals and land plants, many asexual species originate through inter- or intraspecific crosses, and such heterozygous asexuals frequently are more abundant than their sexual relatives in marginal habitats. Although asexual species have been reported in various macroalgal taxa, detailed information regarding their distribution, heterozygosity, and origin is limited. Because many asexual tetrasporophyte strains of Caloglossa vieillardii have been isolated from South Australia, far from their core tropical habitats, we re-examined the distribution range of asexual C. vieillardii and genotyped these and other western Pacific strains using an actin gene marker. We confirmed the marginal distribution of the asexuals; however, a small patch of sexual thalli was newly discovered 450 km further west from asexual populations in South Australia. Three heterozygous genotypes and one homozygous genotypes were detected from nine asexual populations; 21 heterozygous strains were obligately asexual, but one homozygous strain suddenly produced sexual gametophytes after several years of culture. We hypothesized that the most abundant heterozygous genotype (defined as type 3/4) in asexual populations occurred by a cross between type 3 and type 4 allele gametophytes, both of which were isolated from the Australian coasts. In the crossing experiments, certain combinations between type 3 females and type 4 males produced tetrasporophytes, which recycled successive tetrasporophytes. In the culture experiments, whereas both sexual and asexual strains successfully produced tetraspores at 12°C, no sexual strains released carpospores below 14°C. However, it is uncertain whether this slight difference of maturation temperature was related to the marginal distribution of asexual C. vieillardii. © 2017 Phycological Society of America.

  5. Genome-wide Association Studies for Female Fertility Traits in Chinese and Nordic Holsteins.

    Science.gov (United States)

    Liu, Aoxing; Wang, Yachun; Sahana, Goutam; Zhang, Qin; Liu, Lin; Lund, Mogens Sandø; Su, Guosheng

    2017-08-16

    Reduced female fertility could cause considerable economic loss and has become a worldwide problem in the modern dairy industry. The objective of this study was to detect quantitative trait loci (QTL) for female fertility traits in Chinese and Nordic Holsteins using various strategies. First, single-trait association analyses were performed for female fertility traits in Chinese and Nordic Holsteins. Second, the SNPs with P-value Nordic Holsteins. Third, the summary statistics from single-trait association analyses were combined into meta-analyses to: (1) identify common QTL for multiple fertility traits within each Holstein population; (2) detect SNPs which were associated with a female fertility trait across two Holstein populations. A large numbers of QTL were discovered or confirmed for female fertility traits. The QTL segregating at 31.4~34.1 Mb on BTA13, 48.3~51.9 Mb on BTA23 and 34.0~37.6 Mb on BTA28 shared between Chinese and Nordic Holsteins were further ascertained using a validation approach and meta-analyses. Furthermore, multiple novel variants identified in Chinese Holsteins were validated with Nordic data as well as meta-analyses. The genes IL6R, SLC39A12, CACNB2, ZEB1, ZMIZ1 and FAM213A were concluded to be strong candidate genes for female fertility in Holsteins.

  6. Epigenetic variation in asexually reproducing organisms

    NARCIS (Netherlands)

    Verhoeven, K.J.F.; Preite, V.

    2014-01-01

    The role that epigenetic inheritance can play in adaptation may differ between sexuals and asexuals because (1) the dynamics of adaptation differ under sexual and asexual reproduction and the opportunities offered by epigenetic inheritance may affect these dynamics differently; and (2) in asexual

  7. Fertility and sexual function in female Hodgkin lymphoma survivors of reproductive age

    NARCIS (Netherlands)

    Eeltink, C.M.; Incrocci, L.; Witte, B.I.; Meurs, S.; Visser, O.; Huijgens, P.C.; de Leeuw, I.M.

    2013-01-01

    Aims and objectives: To assess the perceived fertility status and to determine the association between perceived fertility status and sexual function, as reported by young female Hodgkin lymphoma survivors. Background: Young female Hodgkin lymphoma survivors are at risk of infertility and impaired

  8. Fertility in female survivors of Hodgkin's lymphoma

    Directory of Open Access Journals (Sweden)

    Irene Biasoli

    2012-01-01

    Full Text Available Currently, Hodgkin's lymphoma is one of the most curable types of cancer. Patients are often young and so the long-term morbidities of treatment have become of increasing concern. Among these, infertility is one of the most challenging consequences for patients in reproductive age. Premature ovarian failure in premenopausal women is a serious long-term sequel of the toxicity of chemotherapy. The main consequence of this syndrome is infertility, but women also present other symptoms related to estrogen deprivation. Different rates of impaired gonadal function are reported, depending on the patient's age, stage of disease, dose and intensity of chemotherapy and the use of radiation therapy. The most established strategy in female infertility is cryopreservation of embryos after in vitro fertilization. Additionally, the use of oral contraceptives or gonadotropinreleasing hormone analogs (GnRH-a during treatment is under study. This review will provide a general overview of the main studies conducted to evaluate the infertility rate among female Hodgkin's lymphoma survivors and risk factors associated to treatment, different end-point definitions for evaluating fertility and also a brief description of the available strategies for fertility preservation.

  9. Coming to an Asexual Identity: Negotiating Identity, Negotiating Desire.

    Science.gov (United States)

    Scherrer, Kristin S

    2008-10-01

    Sexuality is generally considered an important aspect of self-hood. Therefore, individuals who do not experience sexual attraction, and embrace an asexual identity are in a unique position to inform the social construction of sexuality. This study explores the experiences of asexual individuals utilizing open ended Internet survey data from 102 self-identified asexual people. In this paper I describe several distinct aspects of asexual identities: the meanings of sexual, and therefore, asexual behaviors, essentialist characterizations of asexuality, and lastly, interest in romance as a distinct dimension of sexuality. These findings have implications not only for asexual identities, but also for the connections of asexuality with other marginalized sexualities.

  10. Male chimpanzees' grooming rates vary by female age, parity, and fertility status.

    Science.gov (United States)

    Proctor, Darby P; Lambeth, Susan P; Schapiro, Steven J; Brosnan, Sarah F

    2011-10-01

    Copulation preferences in our closest living relative, the chimpanzee, suggest that males prefer older females who have had previous offspring. However, this finding is counter to some behavioral models, which predict that chimpanzee males, as promiscuous breeders with minimal costs to mating, should show little or no preference when choosing mating partners (e.g. should mate indiscriminately). To determine if the preferences indicated by copulations appear in other contexts as well as how they interact, we examined how male chimpanzees' grooming patterns varied amongst females. We found that males' preferences were based on interactions among females' fertility status, age, and parity. First, grooming increased with increasing female parity. We further found an effect of the estrous cycle on grooming; when females were at the lowest point of their cycle, males preferentially groomed parous females at peak reproductive age, but during maximal tumescence, males preferred the oldest multiparous females. Nulliparous females received relatively little grooming regardless of age or fertility. Thus, male chimpanzees apparently chose grooming partners based on both female's experience and fertility, possibly indicating a two-pronged social investment strategy. Male selectivity seems to have evolved to effectively distribute costly social resources in a pattern which may increase their overall reproductive success. © 2011 Wiley-Liss, Inc.

  11. Speciation and reduced hybrid female fertility in house mice.

    Science.gov (United States)

    Suzuki, Taichi A; Nachman, Michael W

    2015-09-01

    In mammals, intrinsic postzygotic isolation has been well studied in males but has been less studied in females, despite the fact that female gametogenesis and pregnancy provide arenas for hybrid sterility or inviability that are absent in males. Here, we asked whether inviability or sterility is observed in female hybrids of Mus musculus domesticus and M. m. musculus, taxa which hybridize in nature and for which male sterility has been well characterized. We looked for parent-of-origin growth phenotypes by measuring adult body weights in F1 hybrids. We evaluated hybrid female fertility by crossing F1 females to a tester male and comparing multiple reproductive parameters between intrasubspecific controls and intersubspecific hybrids. Hybrid females showed no evidence of parent-of-origin overgrowth or undergrowth, providing no evidence for reduced viability. However, hybrid females had smaller litter sizes, reduced embryo survival, fewer ovulations, and fewer small follicles relative to controls. Significant variation in reproductive parameters was seen among different hybrid genotypes, suggesting that hybrid incompatibilities are polymorphic within subspecies. Differences in reproductive phenotypes in reciprocal genotypes were observed and are consistent with cyto-nuclear incompatibilities or incompatibilities involving genomic imprinting. These findings highlight the potential importance of reduced hybrid female fertility in the early stages of speciation. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  12. Female Employment and Fertility in Rural China

    OpenAIRE

    Fang, Hai; Eggleston, Karen N.; Rizzo, John A.; Zeckhauser, Richard Jay

    2010-01-01

    Data on 2,288 married women from the 2006 China Health and Nutrition Survey are deployed to study how off-farm female employment affects fertility. Such employment reduces a married woman’s actual number of children by 0.64, her preferred number by 0.48, and her probability of having more than one child by 54.8 percent. Causality flows in both directions; hence, we use well validated instrumental variables to estimate employment status. China has deep concerns with both female employment an...

  13. Tristania Sumatrana Effect On Female Mus Musculus Fertility

    Science.gov (United States)

    Syamsurizal, S.

    2018-04-01

    The use of traditional medicinal plants are generally based on empirical experience, therefore it is necessary scientific approach in order to bring traditional medicine into medical practice and the formal health services. Tristania sumatrana Miq. is one of the traditional medicinal plants are often used as a contraceptive for women in West Sumatra Tristania sumatrana Miq. extract can prolong the estrous cycle in mice to eleven days. This study aimed to influence Tristania sumatrana Miq. extract treatment on fertility of female mice. Experiments conducted a randomized block design 5x2. Five dose groups: control with no treatment, placebo, treatment with doses of 600, 900 and 1200 mg/kgbw and the old two treatment groups: 10 and 20 days. Fertility parameters studied were ovarian weight follicle Graaf number, the corpus luteum and fetal life. The research proves of Tristania sumatrana Miq. extract treatment causes a decrease very significantly the ovarian weight (treatment of 900 mg/kgbw for 10 days), follicles Graaf number (900 mg/kgbw for 20 days), the corpus luteum (600 mg/kgbw for 10 days) and live fetuses (900 mg/kgbw for 10 days). Tristania sumatrana Miq. extract treatment can lead to decreased fertility of female mice.

  14. Asexuality development among middle aged and older men.

    Science.gov (United States)

    Huang, Yan-Ping; Chen, Bin; Ping, Ping; Wang, Hong-Xiang; Hu, Kai; Yang, Hao; Zhang, Tao; Feng, Tan; Jin, Yan; Han, Yin-Fa; Wang, Yi-Xin; Huang, Yi-Ran

    2014-01-01

    To assess erectile function in middle-aged and older men with asexuality status and further analyze their specific reasons for this condition. Men who had regular sexual intercourse attempts (sex frequency ≥ 1 time per month) were classified into mild erectile dysfunction (ED), moderate to severe ED and non-ED according to International Index of Erectile Function-5, and men having no sexual intercourse attempts for at least 6 months were defined as having an asexuality status. The risk factors associated with ED were collected in a sample of 1,531 Chinese men aged 40 to 80 years, and the self-report reasons for asexuality were recorded in asexual cohort individually. Comparative analyses and multivariate regression models were conducted among these groups. The prevalence rates of ED and asexuality status were 49.9% and 37.2%. The asexuality status group had higher risk factors than the moderate to severe ED group in terms of old age (age ≥ 65, adjusted odds ratio (OR) 17.69 versus (Vs.) 7.19), diabetes (crude OR: 2.40 Vs. 2.36) and hypertension (crude OR: 1.78 Vs. 1.72). The specific reasons for the asexuality status were "erectile difficulty" (52.9%), "do not care about sexuality" (53.5%)", "no longer necessary to have sexuality at this age" (47.7%), "severe stress" (44.4%), "severe fatigue" (26.3%) and "masturbation" (26.9%). Men with an asexual status suffer from higher risk factors for ED than men with moderate to severe ED. The majority of this asexual status could be attributed to a full ED, although the reasons for this transient asexuality also involved sexual attitudes and interests, sexual partners and masturbation.

  15. Asexuality development among middle aged and older men.

    Directory of Open Access Journals (Sweden)

    Yan-Ping Huang

    Full Text Available OBJECTIVES: To assess erectile function in middle-aged and older men with asexuality status and further analyze their specific reasons for this condition. SUBJECTS AND METHODS: Men who had regular sexual intercourse attempts (sex frequency ≥ 1 time per month were classified into mild erectile dysfunction (ED, moderate to severe ED and non-ED according to International Index of Erectile Function-5, and men having no sexual intercourse attempts for at least 6 months were defined as having an asexuality status. The risk factors associated with ED were collected in a sample of 1,531 Chinese men aged 40 to 80 years, and the self-report reasons for asexuality were recorded in asexual cohort individually. Comparative analyses and multivariate regression models were conducted among these groups. RESULTS: The prevalence rates of ED and asexuality status were 49.9% and 37.2%. The asexuality status group had higher risk factors than the moderate to severe ED group in terms of old age (age ≥ 65, adjusted odds ratio (OR 17.69 versus (Vs. 7.19, diabetes (crude OR: 2.40 Vs. 2.36 and hypertension (crude OR: 1.78 Vs. 1.72. The specific reasons for the asexuality status were "erectile difficulty" (52.9%, "do not care about sexuality" (53.5%", "no longer necessary to have sexuality at this age" (47.7%, "severe stress" (44.4%, "severe fatigue" (26.3% and "masturbation" (26.9%. CONCLUSIONS: Men with an asexual status suffer from higher risk factors for ED than men with moderate to severe ED. The majority of this asexual status could be attributed to a full ED, although the reasons for this transient asexuality also involved sexual attitudes and interests, sexual partners and masturbation.

  16. Biological markers of asexuality: Handedness, birth order, and finger length ratios in self-identified asexual men and women.

    Science.gov (United States)

    Yule, Morag A; Brotto, Lori A; Gorzalka, Boris B

    2014-02-01

    Human asexuality is defined as a lack of sexual attraction to anyone or anything and it has been suggested that it may be best conceptualized as a sexual orientation. Non-right-handedness, fraternal birth order, and finger length ratio (2D:4D) are early neurodevelopmental markers associated with sexual orientation. We conducted an Internet study investigating the relationship between self-identification as asexual, handedness, number of older siblings, and self-measured finger-lengths in comparison to individuals of other sexual orientation groups. A total of 325 asexuals (60 men and 265 women; M age, 24.8 years), 690 heterosexuals (190 men and 500 women; M age, 23.5 years), and 268 non-heterosexuals (homosexual and bisexual; 64 men and 204 women; M age, 29.0 years) completed online questionnaires. Asexual men and women were 2.4 and 2.5 times, respectively, more likely to be non-right-handed than their heterosexual counterparts and there were significant differences between sexual orientation groups in number of older brothers and older sisters, and this depended on handedness. Asexual and non-heterosexual men were more likely to be later-born than heterosexual men, and asexual women were more likely to be earlier-born than non-heterosexual women. We found no significant differences between sexual orientation groups on measurements of 2D:4D ratio. This is one of the first studies to test and provide preliminary empirical support for an underlying neurodevelopmental basis to account for the lack of sexual attraction characteristic of asexuality.

  17. Origins of asexuality in Bryobia mites (Acari: Tetranychidae)

    NARCIS (Netherlands)

    Ros, V.I.D.; Breeuwer, J.A.J.; Menken, S.B.J.

    2008-01-01

    Background Obligate asexual reproduction is rare in the animal kingdom. Generally, asexuals are considered evolutionary dead ends that are unable to radiate. The phytophagous mite genus Bryobia contains a large number of asexual species. In this study, we investigate the origin and evolution of

  18. Identification of Phytophthora sojae genes involved in asexual ...

    Indian Academy of Sciences (India)

    ual sporulation or germination. But molecular details about asexual spore development in P. sojae are limited (Tyler et al. 2006). In the present study, to understand the molecular basis of asexual spore development in P. sojae, we investigated gene expression changes involved in asexual sporulation after ul- traviolet (UV) ...

  19. Fertility in female reindeer: the effects of nutrition and growth

    OpenAIRE

    N. J.C. Tyler

    1987-01-01

    Pregnancy rates in juvenile reindeer (Rangifer tarandus) vary considerably both within and between flocks. This potentially has considerable economic significance for reindeer husbandry. This paper discusses the influence of nutrition and growth on fertility in female reindeer using examples taken from the literature. Fertility in reindeer is related to body weight, like in many other mammals, but the relationship is not invariant. Weight-specific pregnancy rates appear to be density dependen...

  20. Fertility and the changing female educational attainment in Croatia

    Directory of Open Access Journals (Sweden)

    Čipin Ivan

    2016-01-01

    Full Text Available This paper investigates the aggregate relationship between cohort fertility and female educational attainment in Croatia. Numerous demographic studies have examined the link between fertility and the level of education. However, newer research indicates that the field of education might also play a role when trying to explain fertility behavior. We contribute to existing literature on macro-level factors related to reproductive outcomes by considering both the level and field of education as possible sources of cohort fertility differentials. The main goal of the present study is to assess the effect of structural changes in educational attainment on cohort fertility decline by means of demographic decomposition techniques. Our analysis is based on detailed 2011 Census data, which provide information on the number of livebirths by mother’s year of birth, birth order, marital status and educational attainment (i.e. the level and field of education. The results of our decomposition analyses reveal the dominance of the structural effect in explaining the overall completed fertility decline in Croatia. We assumed that the changing distribution of women by field of education at least partially accounts for the observed patterns in completed fertility but found no strong evidence in support of the outlined hypothesis.

  1. Fertility preservation in young females with non-gynaecologic malignancy: an emerging speciality.

    LENUS (Irish Health Repository)

    Smyth, C

    2013-06-06

    BACKGROUND: As new treatment and research advances continue to improve the prognosis of cancer patients, oncologists and surgeons are increasingly faced with the issue of fertility protection and preservation. Cancer patients are frequently exposed to gonadotoxic chemotherapy and radiation therapy as a component of their treatment regimens. There are currently various anticipatory techniques available to women who wish to retain future reproductive ability, the most successful of which involves oocyte retrieval followed by in vitro fertilisation and embryo cryopreservation. Innovative methods include oocyte cryopreservation, ovarian follicle cryopreservation and oophoropexy. AIM: The aim of this study was to examine our combined experiences at Mayo General Hospital of treating female patients (<30 years) with non-gynaecologic malignancy and requiring referral to the HARI Unit during a 6-year period (2007-2012). Emphasis was placed on reviewing the fertility-preservation options available. METHODS: The hospital inpatient enquiry system was inspected for all cases of non-gynaecologic malignancy referred for fertility preservation from 2007 to 2012. RESULTS: Three cases of non-gynaecologic malignancy in young females, with an intention to protect and preserve future fertility were identified. The primary treatment plan did not initially incorporate input from a gynaecology or fertility specialist. It was after concerted inquiry and reflection by both physician and patient that oncofertility consultation was sought. CONCLUSION: The responsibility is on both physicians and surgeons to consider a more holistic approach to cancer care in young female patients, which focuses not only on the elimination of malignancy but also on preservation of fertility and quality of life.

  2. Genetic correlations between female fertility and production traits in ...

    African Journals Online (AJOL)

    South African Journal of Animal Science. Journal Home ... Female fertility is increasingly gaining importance in national dairy cattle breeding objectives worldwide. In South Africa ... http://dx.doi.org/10.4314/sajas.v37i3.4090 · AJOL African ...

  3. Influence of female sex and fertile age on neuromyelitis optica spectrum disorders.

    Science.gov (United States)

    Borisow, Nadja; Kleiter, Ingo; Gahlen, Anna; Fischer, Katrin; Wernecke, Klaus-Dieter; Pache, Florence; Ruprecht, Klemens; Havla, Joachim; Krumbholz, Markus; Kümpfel, Tania; Aktas, Orhan; Ringelstein, Marius; Geis, Christian; Kleinschnitz, Christoph; Berthele, Achim; Hemmer, Bernhard; Angstwurm, Klemens; Weissert, Robert; Stellmann, Jan-Patrick; Schuster, Simon; Stangel, Martin; Lauda, Florian; Tumani, Hayrettin; Mayer, Christoph; Zeltner, Lena; Ziemann, Ulf; Linker, Ralf A; Schwab, Matthias; Marziniak, Martin; Then Bergh, Florian; Hofstadt-van Oy, Ulrich; Neuhaus, Oliver; Winkelmann, Alexander; Marouf, Wael; Rückriem, Lioba; Faiss, Jürgen; Wildemann, Brigitte; Paul, Friedemann; Jarius, Sven; Trebst, Corinna; Hellwig, Kerstin

    2017-07-01

    Gender and age at onset are important epidemiological factors influencing prevalence, clinical presentation, and treatment response in autoimmune diseases. To evaluate the impact of female sex and fertile age on aquaporin-4-antibody (AQP4-ab) status, attack localization, and response to attack treatment in patients with neuromyelitis optica (NMO) and its spectrum disorders (neuromyelitis optica spectrum disorder (NMOSD)). Female-to-male ratios, diagnosis at last visit (NMO vs NMOSD), attack localization, attack treatment, and outcome were compared according to sex and age at disease or attack onset. A total of 186 NMO/SD patients (82% female) were included. In AQP4-ab-positive patients, female predominance was most pronounced during fertile age (female-to-male ratio 23:1). Female patients were more likely to be positive for AQP4-abs (92% vs 55%; p 40 years. Our data suggest an influence of sex and age on susceptibility to AQP4-ab-positive NMO/SD. Genetic and hormonal factors might contribute to pathophysiology of NMO/SD.

  4. Female Employment and Fertility: Further Investigation of an Ambivalent Association

    OpenAIRE

    Zeba A. sathar; Shahnaz Kazi

    1989-01-01

    This study of the relationship between female employment and fertility is based on a survey of 1000 ever-married women in Karachi. A distinct pattern of differentials in actual performance and in desired fertility is observed across working and non-working women. Working women are not a homogeneous group, and the differences across six broad occupational groups of working women are more marked than those between working and non-working women. Women in higher status occupations marry much late...

  5. Female Labor Supply and Fertility. Causal Evidence for Latin America

    OpenAIRE

    Darío Tortarolo

    2014-01-01

    In this paper I study the causal relationship between fertility and female labor supply using census data from 14 Latin American countries and the U.S. over the span of three decades (1980, 1990 and 2000). Parental preferences for a gender-balanced family (mixed-sex children) is exploited as a source of exogenous variation in fertility. Although OLS estimates suggest a statistically signi cant negative relationship in the 39 censuses used, instrumental variables approach fails to identify a c...

  6. Sexual Fantasy and Masturbation Among Asexual Individuals: An In-Depth Exploration.

    Science.gov (United States)

    Yule, Morag A; Brotto, Lori A; Gorzalka, Boris B

    2017-01-01

    Human asexuality is generally defined as a lack of sexual attraction. We used online questionnaires to investigate reasons for masturbation, and explored and compared the contents of sexual fantasies of asexual individuals (identified using the Asexual Identification Scale) with those of sexual individuals. A total of 351 asexual participants (292 women, 59 men) and 388 sexual participants (221 women, 167 men) participated. Asexual women were significantly less likely to masturbate than sexual women, sexual men, and asexual men. Asexual women were less likely to report masturbating for sexual pleasure or fun than their sexual counterparts, and asexual men were less likely to report masturbating for sexual pleasure than sexual men. Both asexual women and men were significantly more likely than sexual women and men to report that they had never had a sexual fantasy. Of those who have had a sexual fantasy, asexual women and men were significantly more likely to endorse the response "my fantasies do not involve other people" compared to sexual participants, and consistently scored each sexual fantasy on a questionnaire as being less sexually exciting than did sexual participants. When using an open-ended format, asexual participants were more likely to report having fantasies about sexual activities that did not involve themselves, and were less likely to fantasize about topics such as group sex, public sex, and having an affair. Interestingly, there was a large amount of overlap between sexual fantasies of asexual and sexual participants. Notably, both asexual and sexual participants (both men and women) were equally likely to fantasize about topics such as fetishes and BDSM.

  7. Impact of religious faith & female literacy on fertility in a rural community of west Bengal

    Directory of Open Access Journals (Sweden)

    Mandal N

    2007-01-01

    Full Text Available Background : Role of different social factors on fertility control is evident from different studies. What is the impact of religious faith and female literacy on fertility? Objectives : To study the role of religious faith and female literacy on fertility regulation in a rural community of West Bengal. Methods : Cross Sectional Study at rural field practice area of Department of Community Medicine, NRS Medical College, Kolkata, based on interview of married women in reproductive age group. A total of 671 filled in schedules were analyzed by Epi info package. Results : Average number of pregnancies ever occurred among Muslim mothers (2.8 were higher in comparison with Hindu mothers (1.68. Regarding current fertility, live births in last 2 yrs was more among Muslim mothers (25.2% as compared with their counterparts among Hindu community (12.4%. In both the cases differences were found to be statistically significant. Female literacy was found to have no impact on fertility as a whole, but while stratified, its positive role was evident among Hindu mothers but not among Muslim mothers. Conclusions : Factors, which have made differences in fertility between two religious groups, should be properly assessed and duly addressed for better fertility control in the community.

  8. Female Labor Supply and Fertility in Iran: A Comparison Between Developed, Semi Developed and Less Developed Regions.

    Science.gov (United States)

    Emamgholipour Sefiddashti, Sara; Homaie Rad, Enayatollah; Arab, Mohamad; Bordbar, Shima

    2016-02-01

    Female labor supply has been changed dramatically in the recent yr. In this study, we examined the effects of development on the relationship between fertility and female labor supply. We used data of population and housing census of Iran and estimated three separate models. To do this we employed Logistic Regressions (BLR). The estimation results of our study showed that there was a negative relationship between fertility rate and female labor supply and there are some differences for this relationship in three models. When fertility rate increases, FLS would decreases. In addition, for higher fertility rates, the woman might be forced to work more because of the economic conditions of her family; and negative coefficients of the fertility rate effects on FLS would increase with a diminishing rate.

  9. Female-biased dimorphism underlies a female-specific role for post-embryonic Ilp7 neurons in Drosophila fertility

    Science.gov (United States)

    Castellanos, Monica C.; Tang, Jonathan C. Y.; Allan, Douglas W.

    2013-01-01

    In Drosophila melanogaster, much of our understanding of sexually dimorphic neuronal development and function comes from the study of male behavior, leaving female behavior less well understood. Here, we identify a post-embryonic population of Insulin-like peptide 7 (Ilp7)-expressing neurons in the posterior ventral nerve cord that innervate the reproductive tracts and exhibit a female bias in their function. They form two distinct dorsal and ventral subsets in females, but only a single dorsal subset in males, signifying a rare example of a female-specific neuronal subset. Female post-embryonic Ilp7 neurons are glutamatergic motoneurons innervating the oviduct and are required for female fertility. In males, they are serotonergic/glutamatergic neuromodulatory neurons innervating the seminal vesicle but are not required for male fertility. In both sexes, these neurons express the sex-differentially spliced fruitless-P1 transcript but not doublesex. The male fruitless-P1 isoform (fruM) was necessary and sufficient for serotonin expression in the shared dorsal Ilp7 subset, but although it was necessary for eliminating female-specific Ilp7 neurons in males, it was not sufficient for their elimination in females. By contrast, sex-specific RNA-splicing by female-specific transformer is necessary for female-type Ilp7 neurons in females and is sufficient for their induction in males. Thus, the emergence of female-biased post-embryonic Ilp7 neurons is mediated in a subset-specific manner by a tra- and fru-dependent mechanism in the shared dorsal subset, and a tra-dependent, fru-independent mechanism in the female-specific subset. These studies provide an important counterpoint to studies of the development and function of male-biased neuronal dimorphism in Drosophila. PMID:23981656

  10. Patterns of Asexuality in China: Sexual Activity, Sexual and Romantic Attraction, and Sexual Desire.

    Science.gov (United States)

    Zheng, Lijun; Su, Yanchen

    2018-05-01

    This study examined patterns of asexuality in Chinese asexual people in terms of sexual activities, sexual/romantic attraction, and sexual desire. The sample included 227 (64 men and 163 women) asexual participants and 57 (26 men and 31 women) uncertain asexual participants recruited from social networks for asexual people. The control group included 217 (115 men and 102 women) heterosexual participants recruited from general social networks. Participants scoring 40 or higher on the Asexuality Identification Scale were classified as asexual. Asexual participants reported having less frequent masturbation, sexual intercourse experience, and sexual and romantic attraction compared to heterosexual participants. Lower sexual attraction among asexuals indicated that "people who experience little or no sexual attraction" would be a more appropriate definition of asexuality. The pattern of uncertain asexual participants' sexual/romantic attraction and sexual desire was intermediate between heterosexual and asexual participants. Asexual participants scored significantly lower on dyadic sexual desire and slightly lower on solitary sexual desire than heterosexual participants. There were significant differences in sexual activities and solitary sexual desire among romantic orientation categories. Homoromantic participants showed higher dyadic sexual desire and were more likely to engage in masturbation, indicating the heterogeneity among asexual people. The findings indicated that Chinese asexual people showed similar patterns of asexuality as in Western nations. Specifically, asexual people have little or no sexual attraction, non-partner-orientated sexual desire, and are heterogeneous in sexual activities and sexual desire. This implies similar mechanisms underlying the etiology of asexuality across cultures.

  11. “I am no male or female or any other, I have no sex”: a case report on asexuality

    Directory of Open Access Journals (Sweden)

    Niranjan Hebbar YR

    2017-12-01

    Full Text Available A rather less investigated field of sexual orientation, “asexuality” is spread out within the dimensions on lack of sexual attraction or interest on sexual behaviour, and on self-identification issues, or in combination of these. As sex is considered to be one of the basic instincts of human beings which has been followed since centuries, growing reports of asexuality is a concern against the evolution theory. There is lack of studies to assess the exact prevalence of asexuality in Indian setup. Here we are presenting a case of a 20-year-old male, who presented with self-identity issues with no preference for any particular sexual identity.

  12. The role of oxidative stress in female infertility and in vitro fertilization

    Directory of Open Access Journals (Sweden)

    Joanna Wojsiat

    2017-05-01

    Full Text Available Infertility problem involves many couples of reproductive age. It has been estimated that in Poland 0.7-1.0 million pairs require treatment, while for more than half of them assisted reproduction is the only recommended and effective method. Infertility affects 13 to 15% of the world’s population. A major concern is the age-related decline in female fertility even more that often a decision about pregnancy is taken at later age. Recent studies show that increased production of reactive oxygen species is an important factor in etiopathogenesis of pregnancy and affects female reproduction. It was found that oxidative stress may damage the oocytes and may impair their fertilization capacity. Oxidative stress may also lead to embryo fragmentation and formation of numerous developmental abnormalities, and is regarded to be one of the important reasons of spontaneous and recurrent miscarriage. Moreover, overproduction of reactive oxygen species has a significant impact on the success of in vitro fertilization (IVF.

  13. Asexuality: Sexual Orientation, Paraphilia, Sexual Dysfunction, or None of the Above?

    Science.gov (United States)

    Brotto, Lori A; Yule, Morag

    2017-04-01

    Although lack of sexual attraction was first quantified by Kinsey, large-scale and systematic research on the prevalence and correlates of asexuality has only emerged over the past decade. Several theories have been posited to account for the nature of asexuality. The goal of this review was to consider the evidence for whether asexuality is best classified as a psychiatric syndrome (or a symptom of one), a sexual dysfunction, or a paraphilia. Based on the available science, we believe there is not sufficient evidence to support the categorization of asexuality as a psychiatric condition (or symptom of one) or as a disorder of sexual desire. There is some evidence that a subset of self-identified asexuals have a paraphilia. We also considered evidence supporting the classification of asexuality as a unique sexual orientation. We conclude that asexuality is a heterogeneous entity that likely meets conditions for a sexual orientation, and that researchers should further explore evidence for such a categorization.

  14. Female labour force participation, fertility and public policy in Sweden.

    Science.gov (United States)

    Sundstrom, M; Stafford, F P

    1992-01-01

    2nd only to Ireland in total fertility, Sweden has the highest total fertility (TFR) and female labor force participation rates (FLFPR) among European countries in the late 1980s and early 1990s. 1988 TFR and FLFPR were 1.96 and 80.1%, respectively. This paper considers the role of public policy in creating this unique trend, with particular focus on family leave policy. In 1974, Sweden became the 1st country to allow leave to both parents following childbirth. By 1990, leave duration had grown from an initial 6-month period to 15 months. In addition, subsidized day care, flexible working hours, and economic support to families with children is provided in the context of a family-supportive tax structure. While generous, benefits are related to work and income history. Labor income is replaced at 90% of gross earnings, while the unemployed receive only minimal taxable flat payments. Benefits overall are paid from general taxes. Given that benefits reflect job history and income, and income level tends to rise fastest in the initial stages of employment, women in Sweden postpone childbirth in order to realize wage increases and greater job standing over the short- to medium-terms. In sum, Sweden's policies stimulate both fertility and women's paid work by reducing the costs of having children while requiring parents to be employed to receive full benefits. This paper further reviews the development of parental leave and related policies and compares Swedish fertility, female labor force participation, and parental leave benefits to those of countries in the European Community.

  15. Household consumption, female employment and fertility decisions; A microeconometric analysis

    NARCIS (Netherlands)

    Kalwij, A.S.

    1999-01-01

    This thesis is mainly concerned with a simultaneous analysis of the economic determinants of female employment and fertility decisions on a household level in the Netherlands. In particular, this thesis is interested in the role of the employment decisions of women in the observed behavior that

  16. Impact of Radiotherapy on Fertility, Pregnancy, and Neonatal Outcomes in Female Cancer Patients

    International Nuclear Information System (INIS)

    Wo, Jennifer Y.; Viswanathan, Akila N.

    2009-01-01

    Purpose: Radiation has many potential long-term effects on cancer survivors. Female cancer patients may experience decreased fertility depending on the site irradiated. Oncologists should be aware of these consequences and discuss options for fertility preservation before initiating therapy. Methods and Materials: A comprehensive review of the existing literature was conducted. Studies reporting the outcomes for female patients treated with cranio-spinal, abdominal, or pelvic radiation reporting fertility, pregnancy, or neonatal-related outcomes were reviewed. Results: Cranio-spinal irradiation elicited significant hormonal changes in women that affected their ability to become pregnant later in life. Women treated with abdomino-pelvic radiation have an increased rate of uterine dysfunction leading to miscarriage, preterm labor, low birth weight, and placental abnormalities. Early menopause results from low-dose ovarian radiation. Ovarian transposition may decrease the rates of ovarian dysfunction. Conclusions: There is a dose-dependent relationship between ovarian radiation therapy (RT) and premature menopause. Patients treated with RT must be aware of the impact of treatment on fertility and explore appropriate options.

  17. Overview of industries policies and practices on fertile female and ionizing radiation

    International Nuclear Information System (INIS)

    Burns, L.

    1982-01-01

    Health physicists representing nuclear reactors, government contracting agencies, hospitals and universities, cousulting and personnel firms were surveyed on the policies of their organizations regarding the fertile female and her exposure to ionizing radiation. NCRP Report 39 recommends limiting the exposure of pregnant females to 500 mrem during the gestational period. The responses to the survey questionnaire are summarized

  18. Inter-fertility among female parent clones of pineapple involved in a ...

    African Journals Online (AJOL)

    Inter-fertility among female parent clones of pineapple involved in a 6x6 complete diallel crossing system based on typological approach. AE Issali, AE Badou Nguessan, DF Thiemele, A Amoncho, SB Ngoran Koua, HC Keassemon Kone, ZEB Koffi, A Sangare ...

  19. Female sexual function and fertility after ileal pouch-anal anastomosis.

    Science.gov (United States)

    Hor, Thevy; Lefevre, Jeremie H; Shields, Conor; Chafai, Najim; Tiret, Emmanuel; Parc, Yann

    2016-03-01

    A potential complication in women after ileal pouch-anal anastomosis (IPAA) is sexual impairment and reduced fertility. The aim was to evaluate sexual function and fertility after IPAA. All female patients who underwent an IPAA between 2004 and 2013 were retrospectively included. Sexual function, fertility, and continence were explored by the female sexual function index (FSFI), telephonic interview, and Wexner's score. Among 127 women included, 93 responded to the questionnaires (73.2%). Seventy five were sexually active, and 48 (64%) had normal sexual function (FSFI > 26). In univariate analysis, there was a significant relationship between ulcerative colitis (p = 0.0161), age > 40 years (p = 0.01311), number of bowel movements (p = 0.0238), nocturnal pouch activity (p = 0.0094), use of loperamide (p = 0.0283), and existence of sexual dysfunction. After multivariate analysis, age and nocturnal pouch activity were associated with a worse sexual function (p = 0.0235, OR = 3.3 (1.2-9.9) and p = 0.0094, OR = 4.1 (1.4-13.5)). Of 16 patients who wished to have children, 10 (63%) became pregnant without recourse to in vitro fertilization, of whom 3 had two or more pregnancies. In total, there were 13 children born after IPAA. The mean time between the first pregnancy and surgery was 24.8 ± 22 months. At 12 and 24 months after cessation of contraception, 57 and 67% had at least one pregnancy. While sexual function is impaired in a limited number of patients, the impact of surgery can be regarded as modest. Age and nocturnal pouch activity were some independent factors of worse sexual function. The risk of infertility should not preclude consideration of IPAA as a treatment option.

  20. Asexual sporulation facilitates adaptation

    NARCIS (Netherlands)

    Zhang, Jianhua; Debets, A.J.M.; Verweij, P.E.; Melchers, W.J.G.; Zwaan, B.J.; Schoustra, S.E.

    2015-01-01

    Understanding the occurrence and spread of azole resistance in Aspergillus fumigatus is crucial for public health. It has been hypothesized that asexual sporulation, which is abundant in nature, is essential for phenotypic expression of azole resistance mutations in A. fumigatus facilitating

  1. Coexistence of sexual individuals and genetically isolated asexual counterparts in a thrips.

    Science.gov (United States)

    Kobayashi, Kazuya; Yoshimura, Jin; Hasegawa, Eisuke

    2013-11-21

    Sex is a paradoxical phenomenon because it is less efficient compared with asexual reproduction. To resolve this paradox we need a direct comparison between sexual and asexual forms. In many organisms, however, sexual and asexual forms do not occur in the same habitat, or at the same time. In a few cases where sexual and asexual forms are found in a single population, some (though rare) genetic exchange is usually detected between the two forms. When genetic exchange occurs a direct comparison is impossible. Here we investigate a thrips exhibiting both sexual and asexual forms (lineages) that are morphologically indistinguishable. We examine if the two forms are genetically isolated. Phylogeny based on nuclear genes confirms that the sexual and asexual lineages are genetically differentiated. Thus we demonstrate that the current system has certain advantages over existing and previously used model systems in the evolution of sexual reproduction.

  2. Understanding asexual identity as a means to facilitate culturally competent care: A systematic literature review.

    Science.gov (United States)

    Jones, Catriona; Hayter, Mark; Jomeen, Julie

    2017-12-01

    To provide a contemporary overview of asexuality and the implications this has for healthcare practice. Individuals belonging to sexual minority groups face many barriers in accessing appropriate health care. The term "sexual minority group" is usually used to refer to lesbian women, gay, bisexual and transgender individuals. Anecdotal and research evidence suggests that those who identify as asexual have similar poor experiences. Systematic review and qualitative analysis. This work uses a systematic review and qualitative analysis of the existing interview data from self-identified asexuals, to construct features of the asexual identity. The findings will help practitioners and health professionals develop an understanding of this poorly understood construct. Ultimately this work is aimed at facilitating culturally competent care in the context of asexuality. Qualitative analysis produced three themes, which can be used, not only to frame asexuality in a positive and normalising way, but also to provide greater understanding of asexuality, "romantic differences coupled with sexual indifference," "validation through engagement with asexual communities" and "a diversity of subasexual identities." Having some understanding of what it means to identify as asexual, and respecting the choices made by asexuals can markedly improve the experiences of those who embrace an asexual identity when engaging with health care. Anecdotal evidence, taken from one of the largest asexual online forums, suggests that a number of self-identified asexuals choose not to disclose their identity to healthcare professionals through fear of their asexual status being pathologised, problematised or judged. Given that asexuality is a poorly understood concept, this may be due to lack of understanding on behalf of healthcare providers. The review provides health professionals and practitioners working in clinical settings with some insights of the features of an asexual identity to facilitate

  3. Sexual signalling in female crested macaques and the evolution of primate fertility signals.

    Science.gov (United States)

    Higham, James P; Heistermann, Michael; Saggau, Carina; Agil, Muhammad; Perwitasari-Farajallah, Dyah; Engelhardt, Antje

    2012-06-18

    Female signals of fertility have evolved in diverse taxa. Among the most interesting study systems are those of multimale multifemale group-living primates, where females signal fertility to males through multiple signals, and in which there is substantial inter-specific variation in the composition and reliability of such signals. Among the macaques, some species display reliable behavioural and/or anogenital signals while others do not. One cause of this variation may be differences in male competitive regimes: some species show marked sexual dimorphism and reproductive skew, with males fighting for dominance, while others show low dimorphism and skew, with males queuing for dominance. As such, there is variation in the extent to which rank is a reliable proxy for male competitiveness, which may affect the extent to which it is in females' interest to signal ovulation reliably. However, data on ovulatory signals are absent from species at one end of the macaque continuum, where selection has led to high sexual dimorphism and male reproductive skew. Here we present data from 31 cycles of 19 wild female crested macaques, a highly sexually dimorphic species with strong mating skew. We collected measures of ovarian hormone data from faeces, sexual swelling size from digital images, and male and female behaviour. We show that both sexual swelling size and female proceptivity are graded-signals, but relatively reliable indicators of ovulation, with swelling size largest and female proceptive behaviours most frequent around ovulation. Sexual swelling size was also larger in conceptive cycles. Male mating behaviour was well timed to female ovulation, suggesting that males had accurate information about this. Though probabilistic, crested macaque ovulatory signals are relatively reliable. We argue that in species where males fight over dominance, male dominance rank is surrogate for competitiveness. Under these circumstances it is in the interest of females to increase

  4. Young female cancer survivors' use of fertility care after completing cancer treatment

    Science.gov (United States)

    Kim, Jayeon; Mersereau, Jennifer E.; Su, H. Irene; Whitcomb, Brian W.; Malcarne, Vanessa L.; Gorman, Jessica R.

    2016-01-01

    Purpose To investigate factors associated with female young adult cancer survivors’ (YCS) use of fertility care (FC), including consultation or fertility treatment, after completing their cancer treatment. Methods In this cross-sectional study, females between that ages of 18 and 35 years who had been diagnosed with childhood, adolescent, or young adult cancers completed a 20-min web-based survey that included demographics, reproductive history, use of FC, fertility-related informational needs, and reproductive concerns. Results A total of 204 participants completed the survey. Participants’ mean age was 28.3±4.5 years. Thirty (15%) participants reported using FC after cancer treatment. The majority of participants recalled not receiving enough information about FP options at the time of cancer diagnosis (73%). In multivariable analysis, those with higher concerns about having children because of perceived risk to their personal health (P=0.003) were less likely to report use of FC after cancer treatment. Those who had used FC before cancer treatment (P=0.003) and who felt less fertile than age-matched women (P=0.02) were more likely to use FC after their cancer treatment. Conclusions While most YCS in this cohort believed that they did not receive enough information about fertility and most wanted to have children, the vast majority did not seek FC. The findings of this study offer further evidence of the need for improved education and emotional support regarding reproductive options after cancer treatment is completed. Targeted discussions with YCS about appropriate post-treatment FC options may improve providers’ capacity to help YCS meet their parenthood goals. PMID:26939923

  5. Male-female crosstalk during pollen germination, tube growth and guidance, and double fertilization.

    Science.gov (United States)

    Dresselhaus, Thomas; Franklin-Tong, Noni

    2013-07-01

    Sperm cells of flowering plants are non-motile and thus require transportation to the egg apparatus via the pollen tube to execute double fertilization. During its journey, the pollen tube interacts with various sporophytic cell types that support its growth and guide it towards the surface of the ovule. The final steps of tube guidance and sperm delivery are controlled by the cells of the female gametophyte. During fertilization, cell-cell communication events take place to achieve and maximize reproductive success. Additional layers of crosstalk exist, including self-recognition and specialized processes to prevent self-fertilization and consequent inbreeding. In this review, we focus on intercellular communication between the pollen grain/pollen tube including the sperm cells with the various sporophytic maternal tissues and the cells of the female gametophyte. Polymorphic-secreted peptides and small proteins, especially those belonging to various subclasses of small cysteine-rich proteins (CRPs), reactive oxygen species (ROS)/NO signaling, and the second messenger Ca(2+), play center stage in most of these processes.

  6. Female labour force status and fertility behaviour in Bangladesh: search for policy interventions.

    Science.gov (United States)

    Chaudhury, R H

    1983-09-01

    This paper examines the effect of female labor force participation on fertility behavior because of its immediate relevance to the formulation of small family norm policies. The hypothesis that female employment is inversely related to fertility and positively related to contraceptive use is based on the following assumptions: 1) the satisfactions of outside employment can substitute for those of child rearing; 2) employment delays marriage and increases the probability of women remaining single, thus reducing fertility; 3) every additional child increases the "opportunity cost" (income lost) of a working mother; 4) a working wife has more status with her husband, and the resultant improved spousal communication leads to more contraceptive use; and 5) working women do not have to rely on their children for support in their old age. Using data from various rural and urban surveys of women in Bangladesh (mostly in Dhaka) and data from the 1961 Bangladesh Population Census, the author finds that fertility is reduced and contraceptive use increases for poor and illiterate women if they work outside the home, but employment has no effect on fertility for higher educated women, who have comparatively fewer children to begin with. In Java, Indonesia, it was found that poor working women have the lowest fertility compared to any other higher socioeconomic group. In Thailand, too, it was found that women who worked outside the home and who had modern values had significantly fewer children than other women. Evaluations of income generating programs for women in Bangladesh attest to the fertility lowering success of integrating family planning and health services with employment programs. Employment through these cooperatives has also indirectly lowered fertility by leading to longer birth spacing and marriage delays. The author recommends such integrated programs and cooperatives because they enhance the social and economic status of women, and by doing so, modernize the

  7. Fertility outcome in male and female patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency

    Directory of Open Access Journals (Sweden)

    Mahdi Kamoun

    2014-06-01

    Conclusion: Fertility in male and female patients with CAH is reduced. Early and adequate glucocorticoid therapy along with good compliance, careful monitoring of androgen levels and continuous psychological management could contribute to improved fertility rates in this population, even among those with the severe variant.

  8. Sexual signalling in female crested macaques and the evolution of primate fertility signals

    Directory of Open Access Journals (Sweden)

    Higham James P

    2012-06-01

    Full Text Available Abstract Background Female signals of fertility have evolved in diverse taxa. Among the most interesting study systems are those of multimale multifemale group-living primates, where females signal fertility to males through multiple signals, and in which there is substantial inter-specific variation in the composition and reliability of such signals. Among the macaques, some species display reliable behavioural and/or anogenital signals while others do not. One cause of this variation may be differences in male competitive regimes: some species show marked sexual dimorphism and reproductive skew, with males fighting for dominance, while others show low dimorphism and skew, with males queuing for dominance. As such, there is variation in the extent to which rank is a reliable proxy for male competitiveness, which may affect the extent to which it is in females’ interest to signal ovulation reliably. However, data on ovulatory signals are absent from species at one end of the macaque continuum, where selection has led to high sexual dimorphism and male reproductive skew. Here we present data from 31 cycles of 19 wild female crested macaques, a highly sexually dimorphic species with strong mating skew. We collected measures of ovarian hormone data from faeces, sexual swelling size from digital images, and male and female behaviour. Results We show that both sexual swelling size and female proceptivity are graded-signals, but relatively reliable indicators of ovulation, with swelling size largest and female proceptive behaviours most frequent around ovulation. Sexual swelling size was also larger in conceptive cycles. Male mating behaviour was well timed to female ovulation, suggesting that males had accurate information about this. Conclusion Though probabilistic, crested macaque ovulatory signals are relatively reliable. We argue that in species where males fight over dominance, male dominance rank is surrogate for competitiveness. Under these

  9. Young female cancer patients' experiences with fertility counselling and fertility preservation

    DEFF Research Database (Denmark)

    Hoeg, Didde; Schmidt, Lone; Tryde Macklon, Kirsten

    2016-01-01

    were aware that chemotherapy could destroy their eggs. The participants described how specialized fertility counselling and fertility preservation contributed to a belief in life after cancer, which gave them hope that they would survive their cancer disease. Further, the women described how......Introduction: Fertility counselling for young women newly diagnosed with cancer is an important field of preconceptional counselling. This qualitative, small-scale study explored how young women newly diagnosed with cancer experienced specialized fertility preservation counselling and treatment...... in the public Danish health care system. Methods: Semi-structured, in-depth interviews were conducted with five women below 40 years recently diagnosed with cancer. All women received fertility counselling by a fertility specialist at the Fertility Clinic, University Hospital of Copenhagen, Denmark before...

  10. Sexy males and sexless females: the origin of triploid apomicts.

    Science.gov (United States)

    Muralidhar, P; Haig, D

    2017-05-01

    Apomixis and polyploidy are closely associated in angiosperms, but the evolutionary reason for this association is unknown. Taraxacum officinale, the common dandelion, exists both as diploid sexuals and triploid apomicts. Here, in the context of T. officinale, we provide a model of the evolution of triploid apomicts from diploid sexuals. We posit an apomictic allele that arrests female meiosis in diploids, so that the plant produces diploid egg cells that can develop without fertilization, but haploid pollen. We propose occasional fertilization of diploid egg cells by haploid pollen, resulting in triploid apomicts that produce triploid egg cells but largely nonfunctional pollen. The irreversibility of this process renders diploid partial apomicts evolutionarily short-lived, and results in fixation of triploid apomicts except when they suffer extreme selective disadvantages. Our model can account for the high genetic diversity found in T. officinale triploid populations, because recombinant haploid pollen produced by diploids allows the apomictic allele to spread onto many genetic backgrounds. This leads to multiple clonal lineages in the newly apomictic population, and thereby alleviates some of the usual pitfalls of asexual reproduction.

  11. Profiling the repertoire of phenotypes influenced by environmental cues that occur during asexual reproduction.

    Science.gov (United States)

    Dombrovsky, Aviv; Arthaud, Laury; Ledger, Terence N; Tares, Sophie; Robichon, Alain

    2009-11-01

    The aphid Acyrthosiphon pisum population is composed of different morphs, such as winged and wingless parthenogens, males, and sexual females. The combined effect of reduced photoperiodicity and cold in fall triggers the apparition of sexual morphs. In contrast they reproduce asexually in spring and summer. In our current study, we provide evidence that clonal individuals display phenotypic variability within asexual morph categories. We describe that clones sharing the same morphological features, which arose from the same founder mother, constitute a repertoire of variants with distinct behavioral and physiological traits. Our results suggest that the prevailing environmental conditions influence the recruitment of adaptive phenotypes from a cohort of clonal individuals exhibiting considerable molecular diversity. However, we observed that the variability might be reduced or enhanced by external factors, but is never abolished in accordance with a model of stochastically produced phenotypes. This overall mechanism allows the renewal of colonies from a few adapted individuals that survive drastic episodic changes in a fluctuating environment.

  12. Plasmodium falciparum Calcium-Dependent Protein Kinase 2 Is Critical for Male Gametocyte Exflagellation but Not Essential for Asexual Proliferation

    Directory of Open Access Journals (Sweden)

    Abhisheka Bansal

    2017-10-01

    Full Text Available Drug development efforts have focused mostly on the asexual blood stages of the malaria parasite Plasmodium falciparum. Except for primaquine, which has its own limitations, there are no available drugs that target the transmission of the parasite to mosquitoes. Therefore, there is a need to validate new parasite proteins that can be targeted for blocking transmission. P. falciparum calcium-dependent protein kinases (PfCDPKs play critical roles at various stages of the parasite life cycle and, importantly, are absent in the human host. These features mark them as attractive drug targets. In this study, using CRISPR/Cas9 we successfully knocked out PfCDPK2 from blood-stage parasites, which was previously thought to be an indispensable protein. The growth rate of the PfCDPK2 knockout (KO parasites was similar to that of wild-type parasites, confirming that PfCDPK2 function is not essential for the asexual proliferation of the parasite in vitro. The mature male and female gametocytes of PfCDPK2 KO parasites become round after induction. However, they fail to infect female Anopheles stephensi mosquitoes due to a defect(s in male gametocyte exflagellation and possibly in female gametes.

  13. Attitudes towards motherhood and fertility awareness among 20-40-year-old female healthcare professionals.

    Science.gov (United States)

    Mortensen, Luise Lermark; Hegaard, Hanne Kristine; Andersen, Anders Nyboe; Bentzen, Janne Gasseholm

    2012-12-01

    To explore attitudes towards family formation and fertility awareness among Danish female healthcare professionals. We collected cross-sectional baseline data from a prospective cohort study of 863 women, ranging in age from 20 to 40 years, working at a hospital in Denmark. Information about participants' intentions and attitudes towards family formation and fertility knowledge was gathered by means of a questionnaire. Only 2% of the respondents did not want children. Most women believed that motherhood is important, and hoped to have two to three children. About half of the respondents intended to have their last child after the age of 35 years. The most important prerequisites for family formation included: living in a stable relationship, having completed one's studies, a sound financial situation, a job that can be kept when having children, access to public child day care, and the possibility of travelling. As many as 50% of women underrated the impact of a woman's age on fertility, and overestimated the success rates of assisted reproductive technology (ART) treatments. Many female healthcare professionals contemplated giving birth after the age of 35 years. Knowledge of fertility and ART success rates is needed to make well-informed decisions about when to have children.

  14. Female labour force participation and fertility.

    Science.gov (United States)

    Concepcion, M B

    1974-01-01

    The levels of labor force participation by women in selected Asian countries were recorded in a series of censuses taken over a period of years. These levels were less influenced than male employment levels by economic conditions and more influenced by cultural traits of the country. Postwar trends seem to have fallen in Korea, risen in Singapore and the Philippines, and remained steady in Japan, Malaya, and Thailand. The limitations of these data are mentioned. In Thailand and West Malaysia greater percentages of women worked in agricultural than non-agricultural employment; in the Philippines, where women did not work so much in agricultural pursuits, their jobs were still in traditional rather than in development industries. In the cities of Bangkok, Manila, and Kuala Lumpur, fertility was lower for working than for non-working women. In rural agricultural areas, the fertility of working women was minimally higher, probably due to economic need of lar ger families. It is concluded that urban life separates the employment and the family roles of working women, leading to lowered fertility; this does not occur in rural areas. The creation of new roles for women alternative or supplementary to marriage and motherhood would result in lowered fertility. In high fertility Asian countries, policies directed toward greater participation of women in non-agricultural work and great er exposure to an urban lifestyle might achieve fertility reductions.

  15. Mlh1 is required for female fertility in Drosophila melanogaster: An outcome of effects on meiotic crossing over, ovarian follicles and egg activation.

    Science.gov (United States)

    Vimal, Divya; Kumar, Saurabh; Pandey, Ashutosh; Sharma, Divya; Saini, Sanjay; Gupta, Snigdha; Ravi Ram, Kristipati; Chowdhuri, Debapratim Kar

    2018-03-01

    Mismatch repair (MMR) system, a conserved DNA repair pathway, plays crucial role in DNA recombination and is involved in gametogenesis. The impact of alterations in MMR family of proteins (bacterial MutS and MutL homologues) on mammalian fertility is well documented. However, an insight to the role of MMR in reproduction of non-mammalian organisms is limited. Hence, in the present study, we analysed the impact of mlh1 (a MutL homologue) on meiotic crossing over/recombination and fertility in a genetically tractable model, Drosophila melanogaster. Using mlh1 e00130 hypomorphic allele, we report female specific adverse reproductive outcome for reduced mlh1 in Drosophila: mlh1 e00130 homozygous females had severely reduced fertility while males were fertile. Further, mlh1 e00130 females contained small ovaries with large number of early stages as well as significantly reduced mature oocytes, and laid fewer eggs, indicating discrepancies in egg production and ovulation. These observations contrast the sex independent and/or male specific sterility and normal follicular development as well as ovulation reported so far for MMR family proteins in mammals. However, analogous to the role(s) of mlh1 in meiotic crossing over and DNA repair processes underlying mammalian fertility, ovarian follicles from mlh1 e00130 females contained significantly increased DNA double strand breaks (DSBs) and reduced synaptonemal complex foci. In addition, large proportion of fertilized eggs display discrepancies in egg activation and fail to proceed beyond stage 5 of embryogenesis. Hence, reduction of the Mlh1 protein level leads to defective oocytes that fail to complete embryogenesis after fertilization thereby reducing female fertility. Copyright © 2017 Elsevier GmbH. All rights reserved.

  16. Attitudes towards motherhood and fertility awareness among 20-40-year-old female healthcare professionals

    DEFF Research Database (Denmark)

    Mortensen, Luise Lermark; Hegaard, Hanne Kristine; Andersen, Anders Nyboe

    2012-01-01

    ABSTRACT Objective To explore attitudes towards family formation and fertility awareness among Danish female healthcare professionals. Methods We collected cross-sectional baseline data from a prospective cohort study of 863 women, ranging in age from 20 to 40 years, working at a hospital...... in Denmark. Information about participants' intentions and attitudes towards family formation and fertility knowledge was gathered by means of a questionnaire. Results Only 2% of the respondents did not want children. Most women believed that motherhood is important, and hoped to have two to three children...

  17. Fertility of Czech Females Could Be Lower than Expected: Trends in Future Development of Age-Specific Fertility Rates up to the Year 2050

    Directory of Open Access Journals (Sweden)

    Ondřej Šimpach

    2015-03-01

    Full Text Available Fertility is an essential aspect of reproduction or population replacement of each country. The challenge for demographers is to model fertility and also to estimate its potential future level for the purposes of population projections. In the case of the Czech Republic we have the population projections provided by the Czech Statistical Office (CZSO with overlooking of the total fertility rate in low, medium and high variant. These estimates despite being based on expert judgments, seem to be too positive compared to the past development of the time series of age-specific fertility rates. The aim of this paper is to assess the situation of fertility in the Czech Republic, to analyse the past development of the time series of age-specific fertility rates using one-dimensional Box-Jenkins models and multidimensional stochastic Lee-Carter approach. Together with found trend in time series and principal components estimated by Lee-Carter’s model a forecasts of age-specific fertility rates up to the year 2050 is constructed. Th ese rates are lower than those provided by CZSO in its three variants of the Czech Republic’s population projection, and therefore we discuss the causes at the end of the paper. We would like to point out that the potential future development of Czech females fertility could be lower than which are currently expected.

  18. Oxidative stress and antioxidants: exposure and impact on female fertility

    Science.gov (United States)

    Ruder, Elizabeth H.; Hartman, Terryl J.; Blumberg, Jeffrey; Goldman, Marlene B.

    2009-01-01

    Background Reproductive failure is a significant public health concern. Although relatively little is known about factors affecting fertility and early pregnancy loss, a growing body of literature suggests that environmental and lifestyle factors play an important role. There is sufficient evidence to hypothesize that diet, particularly its constituent antioxidants, and oxidative stress (OS) may influence the timing and maintenance of a viable pregnancy. We hypothesize that conditions leading to OS in the female affect time-to-pregnancy and early pregnancy loss. Methods We review the epidemiology of female infertility related to antioxidant defenses and oxidation and examine potential sources of OS from the ovarian germ cell through the stages of human pregnancy and pregnancy complications related to infertility. Articles were identified through a search of the PubMed database. Results Female OS is a likely mediator of conception and threshold levels for OS exist, dependent on anatomic location and stage of preconception. Conclusions Prospective pregnancy studies with dietary assessment and collection of biological samples prior to conception with endpoints of time-to-pregnancy and early pregnancy loss are needed. PMID:18535004

  19. Alpha-Fetoprotein: From a Diagnostic Biomarker to a Key Role in Female Fertility

    Directory of Open Access Journals (Sweden)

    Christelle De Mees

    2006-01-01

    Full Text Available Alpha-fetoprotein (AFP is a well-known diagnostic biomarker used in medicine to detect fetal developmental anomalies such as neural tube defects or Down's syndrome, or to follow up the development of tumors such as hepatocellular carcinomas. However, and despite the fact that the protein was discovered almost half a century ago, little was known about its physiological function. The study of Afp knock-out mice uncovered a surprising function of AFP: it is essential for female fertility and for expression of normal female behaviors, and this action is mediated through its estrogen binding capacity. AFP sequestrates estrogens and by so doing protects the female developing brain from deleterious (defeminizing/ masculinizing effects of these hormones

  20. Asexual sporulation facilitates adaptation: The emergence of azole resistance in Aspergillus fumigatus.

    Science.gov (United States)

    Zhang, Jianhua; Debets, Alfons J M; Verweij, Paul E; Melchers, Willem J G; Zwaan, Bas J; Schoustra, Sijmen E

    2015-10-01

    Understanding the occurrence and spread of azole resistance in Aspergillus fumigatus is crucial for public health. It has been hypothesized that asexual sporulation, which is abundant in nature, is essential for phenotypic expression of azole resistance mutations in A. fumigatus facilitating subsequent spread through natural selection. Furthermore, the disease aspergilloma is associated with asexual sporulation within the lungs of patients and the emergence of azole resistance. This study assessed the evolutionary advantage of asexual sporulation by growing the fungus under pressure of one of five different azole fungicides over seven weeks and by comparing the rate of adaptation between scenarios of culturing with and without asexual sporulation. Results unequivocally show that asexual sporulation facilitates adaptation. This can be explained by the combination of more effective selection because of the transition from a multicellular to a unicellular stage, and by increased mutation supply due to the production of spores, which involves numerous mitotic divisions. Insights from this study are essential to unravel the resistance mechanisms of sporulating pathogens to chemical compounds and disease agents in general, and for designing strategies that prevent or overcome the emerging threat of azole resistance in particular. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  1. Fertility Preservation in Females with Turner Syndrome: A Comprehensive Review and Practical Guidelines

    Science.gov (United States)

    Oktay, K; Bedoschi, G; Berkowitz, K; Bronson, R; Kashani, B; McGovern, P; Pal, L; Quinn, G; Rubin, K

    2016-01-01

    This article reviews the existing fertility preservation options for females diagnosed with Turner syndrome and provides practical guidelines for the practitioner. Turner syndrome is the most common sex chromosome abnormality in females, occurring in approximately one in 2500 live births. Women with Turner syndrome are at extremely high risk for primary ovarian insufficiency (POI) and infertility. Although about 70–80% have no spontaneous pubertal development and 90% experience primary amenorrhea, the remainder may possess a small residual of ovarian follicles at birth or early childhood. The present challenge is to identify these women as early in life as is possible, so as to allow them to benefit from a variety of existing fertility preservation options. To maximize the benefits of fertility preservation, all women with Turner syndrome should be evaluated by an expert as soon as possible in childhood as the vast majority will have their ovarian reserve depleted before adulthood. Cryopreservation of mature oocytes and embryos is a proven fertility preservation approach, while cryopreservation of ovarian tissue is a promising technique with a growing number of live births, but remain investigational. Oocyte cryopreservation has been performed in children with Turner syndrome as young as 13 and ovarian tissue cryopreservation in prepubertal children affected. However, current efficacy of these approaches is unknown in this cohort.. For those who have already lost their ovarian reserve, oocyte or embryo donation and adoption are strategies that allow fulfillment of desire for parenting. For those with Turner syndrome related cardiac contraindications to pregnancy, utilization of gestational surrogacy allows the possibility of biological parenting by using their own oocytes. Alternatively, gestational surrogacy can serve to carry pregnancy resulting from the use of donor oocytes or embryos, if needed. PMID:26485320

  2. Fibroblast growth factor 21 has no direct role in regulating fertility in female mice

    Directory of Open Access Journals (Sweden)

    Garima Singhal

    2016-08-01

    Full Text Available Objective: Reproduction is an energetically expensive process. Insufficient calorie reserves, signaled to the brain through peripheral signals such as leptin, suppress fertility. Recently, fibroblast growth factor 21 (FGF21 was implicated as a signal from the liver to the hypothalamus that directly inhibits the hypothalamic–gonadotropin axis during fasting and starvation. However, FGF21 itself increases metabolic rate and can induce weight loss, which suggests that the effects of FGF21 on fertility may not be direct and may reflect changes in energy balance. Methods: To address this important question, we evaluated fertility in several mouse models with elevated FGF21 levels including ketogenic diet fed mice, fasted mice, mice treated with exogenous FGF21 and transgenic mice over-expressing FGF21. Results: We find that ketogenic diet fed mice remain fertile despite significant elevation in serum FGF21 levels. Absence of FGF21 does not alter transient infertility induced by fasting. Centrally infused FGF21 does not suppress fertility despite its efficacy in inducing browning of inguinal white adipose tissue. Furthermore, a high fat diet (HFD can restore fertility of female FGF21-overexpressing mice, a model of growth restriction, even in the presence of supraphysiological serum FGF21 levels. Conclusions: We conclude that FGF21 is not a direct physiological regulator of fertility in mice. The infertility observed in FGF21 overexpressing mice is likely driven by the increased energy expenditure and consequent excess calorie requirements resulting from high FGF21 levels. Keywords: FGF21, Fertility, Leptin, Hypothalamic action

  3. The exact distributions of F(IS under partial asexuality in small finite populations with mutation.

    Directory of Open Access Journals (Sweden)

    Solenn Stoeckel

    Full Text Available Reproductive systems like partial asexuality participate to shape the evolution of genetic diversity within populations, which is often quantified by the inbreeding coefficient F IS. Understanding how those mating systems impact the possible distributions of F IS values in theoretical populations helps to unravel forces shaping the evolution of real populations. We proposed a population genetics model based on genotypic states in a finite population with mutation. For populations with less than 400 individuals, we assessed the impact of the rates of asexuality on the full exact distributions of F IS, the probabilities of positive and negative F IS, the probabilities of fixation and the probabilities to observe changes in the sign of F IS over one generation. After an infinite number of generations, we distinguished three main patterns of effects of the rates of asexuality on genetic diversity that also varied according to the interactions of mutation and genetic drift. Even rare asexual events in mainly sexual populations impacted the balance between negative and positive F IS and the occurrence of extreme values. It also drastically modified the probability to change the sign of F IS value at one locus over one generation. When mutation prevailed over genetic drift, increasing rates of asexuality continuously increased the variance of F IS that reached its highest value in fully asexual populations. In consequence, even ancient asexual populations showed the entire F IS spectrum, including strong positive F IS. The prevalence of heterozygous loci only occurred in full asexual populations when genetic drift dominated.

  4. Low-Dose Aspirin Treatment Alleviates Gamma Irradiation Impaired Fertility in Female Albino Rats

    International Nuclear Information System (INIS)

    Ibrahim, M.F.

    2013-01-01

    Recent experimental evidence suggests that Aspirin (acetylsalicylic acid), the extensively prescribed analgesic, can improve female fertility by suppressing the prostaglandin (PG) biosynthesis and modulating the uterine circulation. Aspirin has also been found to exhibit a protective ability on the radiation induced oxidative stress. Thus the present work aims to investigate the effect of oral low-dose Aspirin treatment on the radiation induced female reproductive disturbance. Adult female rats were used in the current experiment. All rat group treatments started at the onset of the proestrus phase and terminated at the diestrus encompassing 2 complete estrus cycles. Subsequently, the rats were divided into 4 equal groups: Group 1-Control: female rats receiving distilled water via an oral gavage; Group 2- Irradiation: female rats subjected to 6 Gy gamma rays at the proestrus cycle and receiving distilled water; Group 3-Aspirin: rats orally administered a daily dose of 7mg/kg body weight aspirin dissolved in distilled water via an oral gavage and Group 4- Irradiation + Aspirin: female rats irradiated as group 2 and receiving aspirin treatment. A number of rats from each experimental group were allowed to mate following every treatment to serve as Control mated (Subgroup 1), Irradiated mated (Subgroup 2), Aspirin administered mated (Subgroup 3) and Irradiated + Aspirin treated mated (Subgroup 4). At the assigned day of the second estrus cycle completion, blood was collected from Groups 1-4 for subsequent hormonal assay, lipid peroxides and glutathione (GSH) estimation whereas Subgroups 1-4 were carefully monitored for reproduction and infertility rates. Results have shown that the 6 Gy γ- irradiation of the rats at the proestrus cycle (Group 2) caused a decrease in follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL) and estradiol (E2) levels associated with a drastic increase in the progesterone levels in addition to the significant

  5. Cdc20 is critical for meiosis I and fertility of female mice.

    Directory of Open Access Journals (Sweden)

    Fang Jin

    2010-09-01

    Full Text Available Chromosome missegregation in germ cells is an important cause of unexplained infertility, miscarriages, and congenital birth defects in humans. However, the molecular defects that lead to production of aneuploid gametes are largely unknown. Cdc20, the activating subunit of the anaphase-promoting complex/cyclosome (APC/C, initiates sister-chromatid separation by ordering the destruction of two key anaphase inhibitors, cyclin B1 and securin, at the transition from metaphase to anaphase. The physiological significance and full repertoire of functions of mammalian Cdc20 are unclear at present, mainly because of the essential nature of this protein in cell cycle progression. To bypass this problem we generated hypomorphic mice that express low amounts of Cdc20. These mice are healthy and have a normal lifespan, but females produce either no or very few offspring, despite normal folliculogenesis and fertilization rates. When mated with wild-type males, hypomorphic females yield nearly normal numbers of fertilized eggs, but as these embryos develop, they become malformed and rarely reach the blastocyst stage. In exploring the underlying mechanism, we uncover that the vast majority of these embryos have abnormal chromosome numbers, primarily due to chromosome lagging and chromosome misalignment during meiosis I in the oocyte. Furthermore, cyclin B1, cyclin A2, and securin are inefficiently degraded in metaphase I; and anaphase I onset is markedly delayed. These results demonstrate that the physiologically effective threshold level of Cdc20 is high for female meiosis I and identify Cdc20 hypomorphism as a mechanism for chromosome missegregation and formation of aneuploid gametes.

  6. A sterile sperm caste protects brother fertile sperm from female-mediated death in Drosophila pseudoobscura

    DEFF Research Database (Denmark)

    Holman, Luke; Snook, Rhonda R

    2008-01-01

    antispermicidal mechanisms have been definitively identified. One such adaptation may be the enigmatic infertile sperm morphs or "parasperm" produced by many species, which have been hypothesized to protect their fertile brother "eusperm" from spermicide [2, 3]. Here, we show that female Drosophila pseudoobscura...

  7. Awareness, knowledge, and perceptions of infertility, fertility assessment, and assisted reproductive technologies in the era of oocyte freezing among female and male university students.

    Science.gov (United States)

    Meissner, C; Schippert, C; von Versen-Höynck, Frauke

    2016-06-01

    The aims of our study were to analyze university student's knowledge and attitude towards parenthood, female fertility, fertility assessment, and oocyte freezing and to explore associations between these aspects and the participant's sex or degree program they were registered for. The study was designed as an online-based cross-sectional survey. A total of 1144 participants answered 27 questions. The data were analyzed using descriptive statistics. Linear regression models were employed to explore associations between sex or university program and attitude towards parenthood, fertility assessment, and oocyte freezing. Female students and students of non-medical degree programs were more likely to plan to have children earlier than male students or students of medical degree programs. Female sex or medical degree program was associated with an overall better knowledge about women's fertility. The better the participant's knowledge about fertility, the more likely the students would consider assisted reproductive technology (ART) treatments as an option to become pregnant when ovarian reserve is low. The majority of students knew the principal of oocyte freezing but would not consider using it. However, in the case of a low ovarian reserve, oocyte freezing would be accepted as an option. Students planned to have children at an age when women's fertility is already declining. Gaps in knowledge about female fertility and the potential of ART were more pronounced in male students and students of non-medical degree programs suggesting an increase of fertility awareness is necessary in these groups to prevent them from infertility and unwanted childlessness.

  8. Fertility Treatments for Females

    Science.gov (United States)

    ... on: The underlying cause of the problem The woman's age Her history of previous pregnancies How long she has had infertility issues The presence or absence of male factor infertility Fertility treatments are most likely to benefit women whose infertility is due to problems with ovulation. ...

  9. The Key Role of Epigenetics in the Persistence of Asexual Lineages

    Directory of Open Access Journals (Sweden)

    Emilie Castonguay

    2012-01-01

    Full Text Available Asexual organisms, often perceived as evolutionary dead ends, can be long-lived and geographically widespread. We propose that epigenetic mechanisms could play a crucial role in the evolutionary persistence of these lineages. Genetically identical organisms could rely on phenotypic plasticity to face environmental variation. Epigenetic modifications could be the molecular mechanism enabling such phenotypic plasticity; they can be influenced by the environment and act at shorter timescales than mutation. Recent work on the asexual vertebrate Chrosomus eos-neogaeus (Pisces: Cyprinidae provides broad insights into the contribution of epigenetics in genetically identical individuals. We discuss the extension of these results to other asexual organisms, in particular those resulting from interspecific hybridizations. We finally develop on the evolutionary relevance of epigenetic variation in the context of heritability.

  10. Morphological peculiarities of bryophytes asexual organs

    Directory of Open Access Journals (Sweden)

    Oksana Lobachevska

    2013-04-01

    Full Text Available The main types of brood organs of dominant bryophyte species on dumps of the mining factories were determined. The special features of morphology, localization and genesis of specialized asexual propagula and gemmae were detected. The analysis of their role in reproductive strategy of colonist species was conducted.

  11. Female labour force participation in Peru: an analysis using the world fertility survey.

    OpenAIRE

    Rodgers G; Viry D

    1980-01-01

    ILO pub-WEP pub. Working paper analysing woman worker labour force participation trends in Peru based on a world fertility survey - examines female wages employment, unpaid work, occupational structure, labour supply determinants such as population variables (incl. Family structure, marital status, age, internal migration and educational level), husband's characteristics, etc., in rural areas and urban areas, with a view to estimating participation economic models. References.

  12. On low fertility from the aspect of the economic activity of female population: Possibilities and restrictions in encouragement of childbearing

    Directory of Open Access Journals (Sweden)

    Šobot Ankica

    2014-01-01

    Full Text Available Below replacement fertility was the outcome of changes in the education and socio-professional structure of women, as well as modifications in values and life aspirations. On the other hand, economic strengthening of women and encourage-ment of jobs which require greater dedication and more of their time are important aspects of achieving gender equality. These two circumstances gave rise to contemplations on the connection between economic activities of female population and the level of births in postindustrial societies. The aim of this article is to point out to the positive influence of female employment on the fertility level, as a capacity for encouraging births in Serbia. When observing the most developed European countries, it can be noticed that greater birth rates are noted in those countries in which there are greater economic activity and employment rates of female population. Furthermore, a series of researches and comparative analyses confirm the positive relation between female employment and fertility. The differences regarding of birth rates among European welfare states are seen as a result of the possibilities of female employment, reconciliation between work and parenthood and the division of gender roles within the family. The influence of economic activity on fertility levels is determined by an institutional framework of family support and gender equality (Engelhardt and Prskawetz, 2004, Neyer, 2006; Andersson and Scott, 2007; Rovny, A.E. 2011; Seeleib-Kaise and Toivonen, 2011. During the first decade of the 21st century, the birth rates in Serbia were by about 30% lower than in the countries which had the highest fertility within European frameworks. The traditional labor division in the household and parenthood produces conflicts between families and employment, recognized in the practices of everyday life (Blagojević, 1997; Blagojević-Hjuson, 2013 and standpoints on the relation between parenthood and employment

  13. Omics Analyses of Trichoderma reesei CBS999.97 and QM6a Indicate the Relevance of Female Fertility to Carbohydrate-Active Enzyme and Transporter Levels.

    Science.gov (United States)

    Tisch, Doris; Pomraning, Kyle R; Collett, James R; Freitag, Michael; Baker, Scott E; Chen, Chia-Ling; Hsu, Paul Wei-Che; Chuang, Yu Chien; Schuster, Andre; Dattenböck, Christoph; Stappler, Eva; Sulyok, Michael; Böhmdorfer, Stefan; Oberlerchner, Josua; Wang, Ting-Fang; Schmoll, Monika

    2017-11-15

    The filamentous fungus Trichoderma reesei is found predominantly in the tropics but also in more temperate regions, such as Europe, and is widely known as a producer of large amounts of plant cell wall-degrading enzymes. We sequenced the genome of the sexually competent isolate CBS999.97, which is phenotypically different from the female sterile strain QM6a but can cross sexually with QM6a. Transcriptome data for growth on cellulose showed that entire carbohydrate-active enzyme (CAZyme) families are consistently differentially regulated between these strains. We evaluated backcrossed strains of both mating types, which acquired female fertility from CBS999.97 but maintained a mostly QM6a genetic background, and we could thereby distinguish between the effects of strain background and female fertility or mating type. We found clear regulatory differences associated with female fertility and female sterility, including regulation of CAZyme and transporter genes. Analysis of carbon source utilization, transcriptomes, and secondary metabolites in these strains revealed that only a few changes in gene regulation are consistently correlated with different mating types. Different strain backgrounds (QM6a versus CBS999.97) resulted in the most significant alterations in the transcriptomes and in carbon source utilization, with decreased growth of CBS999.97 on several amino acids (for example proline or alanine), which further correlated with the downregulation of genes involved in the respective pathways. In combination, our findings support a role of fertility-associated processes in physiology and gene regulation and are of high relevance for the use of sexual crossing in combining the characteristics of two compatible strains or quantitative trait locus (QTL) analysis. IMPORTANCE Trichoderma reesei is a filamentous fungus with a high potential for secretion of plant cell wall-degrading enzymes. We sequenced the genome of the fully fertile field isolate CBS999.97 and

  14. Female parthenogenetic apomixis and androsporogenetic parthenogenesis in embryonal cells of Araucaria angustifolia: interpolation of progenesis and asexual heterospory in an artificial sporangium.

    Science.gov (United States)

    Durzan, Don J

    2012-09-01

    Cell fate, development timing and occurrence of reproductive versus apomictic development in gymnosperms are shown to be influenced by culture conditions in vitro. In this study, female parthenogenetic apomixis (fPA), androsporogenetic parthenogenesis (mAP) and progenesis were demonstrated using embryonal initials of Araucaria angustifolia in scaled-up cell suspensions passing through a single-cell bottleneck in darkness and in an artificial sporangium (AS). Expression was based on defined nutrition, hormones and feedforward-adaptive feedback process controls at 23-25 °C and in darkness. In fPA, the nucleus of an embryonal initial undergoes endomitosis and amitosis, forming a diploid egg-equivalent and an apoptotic ventral canal nucleus in a transdifferentiated archegonial tube. Discharge of egg-equivalent cells as parthenospores and their dispersal into the aqueous culture medium were followed by free-nuclear conifer-type proembryogenesis. This replaced the plesiomorphic and central features of proembryogenesis in Araucariaceae. Protoplasmic fusions of embryonal initials were used to reconstruct heterokaryotic expressions of fPA in multiwell plates. In mAP, restitutional meiosis (automixis) was responsible for androsporogenesis and the discharge of monads, dyads, tetrads and polyads. In a display of progenesis, reproductive development was brought to an earlier ontogenetic stage and expressed by embryonal initials. Colchicine increased polyploidy, but androspore formation became aberrant and fragmented. Aberrant automixis led to the formation of chromosomal bouquets, which contributed to genomic silencing in embryonal initials, cytomixis and the formation of pycnotic micronucleated cells. Dispersal of female and male parthenospores displayed heteromorphic asexual heterospory in an aqueous environment.

  15. Substance p regulates puberty onset and fertility in the female mouse.

    Science.gov (United States)

    Simavli, Serap; Thompson, Iain R; Maguire, Caroline A; Gill, John C; Carroll, Rona S; Wolfe, Andrew; Kaiser, Ursula B; Navarro, Víctor M

    2015-06-01

    Puberty is a tightly regulated process that leads to reproductive capacity. Kiss1 neurons are crucial in this process by stimulating GnRH, yet how Kiss1 neurons are regulated remains unknown. Substance P (SP), an important neuropeptide in pain perception, induces gonadotropin release in adult mice in a kisspeptin-dependent manner. Here, we assessed whether SP, through binding to its receptor NK1R (neurokinin 1 receptor), participates in the timing of puberty onset and fertility in the mouse. We observed that 1) selective NK1R agonists induce gonadotropin release in prepubertal females; 2) the expression of Tac1 (encoding SP) and Tacr1 (NK1R) in the arcuate nucleus is maximal before puberty, suggesting increased SP tone; 3) repeated exposure to NK1R agonists prepubertally advances puberty onset; and 4) female Tac1(-/-) mice display delayed puberty; moreover, 5) SP deficiency leads to subfertility in females, showing fewer corpora lutea and antral follicles and leading to decreased litter size. Thus, our findings support a role for SP in the stimulation of gonadotropins before puberty, acting via Kiss1 neurons to stimulate GnRH release, and its involvement in the attainment of full reproductive capabilities in female mice.

  16. Adaptations to different habitats in sexual and asexual populations of parasitoid wasps: a meta-analysis

    OpenAIRE

    Amat, I; Kacelnik, A; van Alphen, JJM; Desouhant, E; Bernstein, C

    2017-01-01

    Background Coexistence of sexual and asexual populations remains a key question in evolutionary ecology. We address the question how an asexual and a sexual form of the parasitoid Venturia canescens can coexist in southern Europe. We test the hypothesis that both forms are adapted to different habitats within their area of distribution. Sexuals inhabit natural environments that are highly unpredictable, and where density of wasps and their hosts is low and patchily distributed. Asexuals in...

  17. Severe Fertility Effects of sheepish Sperm Caused by Failure To Enter Female Sperm Storage Organs in Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Masatoshi Tomaru

    2018-01-01

    Full Text Available In Drosophila, mature sperm are transferred from males to females during copulation, stored in the sperm storage organs of females, and then utilized for fertilization. Here, we report a gene named sheepish (shps of Drosophila melanogaster that is essential for sperm storage in females. shps mutant males, although producing morphologically normal and motile sperm that are effectively transferred to females, produce very few offspring. Direct counts of sperm indicated that the primary defect was correlated to failure of shps sperm to migrate into the female sperm storage organs. Increased sperm motion parameters were seen in the control after transfer to females, whereas sperm from shps males have characteristics of the motion parameters different from the control. The few sperm that occasionally entered the female sperm storage organs showed no obvious defects in fertilization and early embryo development. The female postmating responses after copulation with shps males appeared normal, at least with respect to conformational changes of uterus, mating plug formation, and female remating rates. The shps gene encodes a protein with homology to amine oxidases, including as observed in mammals, with a transmembrane region at the C-terminal end. The shps mutation was characterized by a nonsense replacement in the third exon of CG13611, and shps was rescued by transformants of the wild-type copy of CG13611. Thus, shps may define a new class of gene responsible for sperm storage.

  18. How Large Asexual Populations Adapt

    Science.gov (United States)

    Desai, Michael

    2007-03-01

    We often think of beneficial mutations as being rare, and of adaptation as a sequence of selected substitutions: a beneficial mutation occurs, spreads through a population in a selective sweep, then later another beneficial mutation occurs, and so on. This simple picture is the basis for much of our intuition about adaptive evolution, and underlies a number of practical techniques for analyzing sequence data. Yet many large and mostly asexual populations -- including a wide variety of unicellular organisms and viruses -- live in a very different world. In these populations, beneficial mutations are common, and frequently interfere or cooperate with one another as they all attempt to sweep simultaneously. This radically changes the way these populations adapt: rather than an orderly sequence of selective sweeps, evolution is a constant swarm of competing and interfering mutations. I will describe some aspects of these dynamics, including why large asexual populations cannot evolve very quickly and the character of the diversity they maintain. I will explain how this changes our expectations of sequence data, how sex can help a population adapt, and the potential role of ``mutator'' phenotypes with abnormally high mutation rates. Finally, I will discuss comparisons of these predictions with evolution experiments in laboratory yeast populations.

  19. Cryptic sexual populations account for genetic diversity and ecological success in a widely distributed, asexual fungus-growing ant.

    Science.gov (United States)

    Rabeling, Christian; Gonzales, Omar; Schultz, Ted R; Bacci, Maurício; Garcia, Marcos V B; Verhaagh, Manfred; Ishak, Heather D; Mueller, Ulrich G

    2011-07-26

    Sex and recombination are central processes in life generating genetic diversity. Organisms that rely on asexual propagation risk extinction due to the loss of genetic diversity and the inability to adapt to changing environmental conditions. The fungus-growing ant species Mycocepurus smithii was thought to be obligately asexual because only parthenogenetic populations have been collected from widely separated geographic localities. Nonetheless, M. smithii is ecologically successful, with the most extensive distribution and the highest population densities of any fungus-growing ant. Here we report that M. smithii actually consists of a mosaic of asexual and sexual populations that are nonrandomly distributed geographically. The sexual populations cluster along the Rio Amazonas and the Rio Negro and appear to be the source of independently evolved and widely distributed asexual lineages, or clones. Either apomixis or automixis with central fusion and low recombination rates is inferred to be the cytogenetic mechanism underlying parthenogenesis in M. smithii. Males appear to be entirely absent from asexual populations, but their existence in sexual populations is indicated by the presence of sperm in the reproductive tracts of queens. A phylogenetic analysis of the genus suggests that M. smithii is monophyletic, rendering a hybrid origin of asexuality unlikely. Instead, a mitochondrial phylogeny of sexual and asexual populations suggests multiple independent origins of asexual reproduction, and a divergence-dating analysis indicates that M. smithii evolved 0.5-1.65 million years ago. Understanding the evolutionary origin and maintenance of asexual reproduction in this species contributes to a general understanding of the adaptive significance of sex.

  20. Through the smoke: Use of in vivo and in vitro cigarette smoking models to elucidate its effect on female fertility

    International Nuclear Information System (INIS)

    Camlin, Nicole J.; McLaughlin, Eileen A.; Holt, Janet E.

    2014-01-01

    A finite number of oocytes are established within the mammalian ovary prior to birth to form a precious ovarian reserve. Damage to this limited pool of gametes by environmental factors such as cigarette smoke and its constituents therefore represents a significant risk to a woman's reproductive capacity. Although evidence from human studies to date implicates a detrimental effect of cigarette smoking on female fertility, these retrospective studies are limited and present conflicting results. In an effort to more clearly understand the effect of cigarette smoke, and its chemical constituents, on female fertility, a variety of in vivo and in vitro animal models have been developed. This article represents a systematic review of the literature regarding four of experimental model types: 1) direct exposure of ovarian cells and follicles to smoking constituents’ in vitro, 2) direct exposure of whole ovarian tissue with smoking constituents in vitro, 3) whole body exposure of animals to smoking constituents and 4) whole body exposure of animals to cigarette smoke. We summarise key findings and highlight the strengths and weaknesses of each model system, and link these to the molecular mechanisms identified in smoke-induced fertility changes. - Highlights: • In vivo exposure to individual cigarette smoke chemicals alters female fertility. • The use of in vitro models in determining molecular mechanisms • Whole cigarette smoke inhalation animal models negatively affect ovarian function

  1. Through the smoke: Use of in vivo and in vitro cigarette smoking models to elucidate its effect on female fertility

    Energy Technology Data Exchange (ETDEWEB)

    Camlin, Nicole J. [School of Environment and Life Sciences, University of Newcastle, Callaghan, NSW 2308 (Australia); McLaughlin, Eileen A., E-mail: eileen.mclaughlin@newcastle.edu.au [School of Environment and Life Sciences, University of Newcastle, Callaghan, NSW 2308 (Australia); Holt, Janet E. [School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW 2308 (Australia)

    2014-12-15

    A finite number of oocytes are established within the mammalian ovary prior to birth to form a precious ovarian reserve. Damage to this limited pool of gametes by environmental factors such as cigarette smoke and its constituents therefore represents a significant risk to a woman's reproductive capacity. Although evidence from human studies to date implicates a detrimental effect of cigarette smoking on female fertility, these retrospective studies are limited and present conflicting results. In an effort to more clearly understand the effect of cigarette smoke, and its chemical constituents, on female fertility, a variety of in vivo and in vitro animal models have been developed. This article represents a systematic review of the literature regarding four of experimental model types: 1) direct exposure of ovarian cells and follicles to smoking constituents’ in vitro, 2) direct exposure of whole ovarian tissue with smoking constituents in vitro, 3) whole body exposure of animals to smoking constituents and 4) whole body exposure of animals to cigarette smoke. We summarise key findings and highlight the strengths and weaknesses of each model system, and link these to the molecular mechanisms identified in smoke-induced fertility changes. - Highlights: • In vivo exposure to individual cigarette smoke chemicals alters female fertility. • The use of in vitro models in determining molecular mechanisms • Whole cigarette smoke inhalation animal models negatively affect ovarian function.

  2. Genome Scan Detects Quantitative Trait Loci Affecting Female Fertility Traits in Danish and Swedish Holstein Cattle

    DEFF Research Database (Denmark)

    Höglund, Johanna Karolina; Guldbrandtsen, B; Su, G

    2009-01-01

    Data from the joint Nordic breeding value prediction for Danish and Swedish Holstein grandsire families were used to locate quantitative trait loci (QTL) for female fertility traits in Danish and Swedish Holstein cattle. Up to 36 Holstein grandsires with over 2,000 sons were genotyped for 416 mic...... for QTL segregating on Bos taurus chromosome (BTA)1, BTA7, BTA10, and BTA26. On each of these chromosomes, several QTL were detected affecting more than one of the fertility traits investigated in this study. Evidence for segregation of additional QTL on BTA2, BTA9, and BTA24 was found...

  3. Adaptations to different habitats in sexual and asexual populations of parasitoid wasps: a meta-analysis.

    Science.gov (United States)

    Amat, Isabelle; van Alphen, Jacques J M; Kacelnik, Alex; Desouhant, Emmanuel; Bernstein, Carlos

    2017-01-01

    Coexistence of sexual and asexual populations remains a key question in evolutionary ecology. We address the question how an asexual and a sexual form of the parasitoid Venturia canescens can coexist in southern Europe. We test the hypothesis that both forms are adapted to different habitats within their area of distribution. Sexuals inhabit natural environments that are highly unpredictable, and where density of wasps and their hosts is low and patchily distributed. Asexuals instead are common in anthropic environments (e.g., grain stores) where host outbreaks offer periods when egg-load is the main constraint on reproductive output. We present a meta-analysis of known adaptations to these habitats. Differences in behavior, physiology and life-history traits between sexual and asexual wasps were standardized in term of effect size (Cohen's d value; Cohen, 1988). Seeking consilience from the differences between multiple traits, we found that sexuals invest more in longevity at the expense of egg-load, are more mobile, and display higher plasticity in response to thermal variability than asexual counterparts. Thus, each form has consistent multiple adaptations to the ecological circumstances in the contrasting environments.

  4. Adaptations to different habitats in sexual and asexual populations of parasitoid wasps: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Isabelle Amat

    2017-09-01

    Full Text Available Background Coexistence of sexual and asexual populations remains a key question in evolutionary ecology. We address the question how an asexual and a sexual form of the parasitoid Venturia canescens can coexist in southern Europe. We test the hypothesis that both forms are adapted to different habitats within their area of distribution. Sexuals inhabit natural environments that are highly unpredictable, and where density of wasps and their hosts is low and patchily distributed. Asexuals instead are common in anthropic environments (e.g., grain stores where host outbreaks offer periods when egg-load is the main constraint on reproductive output. Methods We present a meta-analysis of known adaptations to these habitats. Differences in behavior, physiology and life-history traits between sexual and asexual wasps were standardized in term of effect size (Cohen’s d value; Cohen, 1988. Results Seeking consilience from the differences between multiple traits, we found that sexuals invest more in longevity at the expense of egg-load, are more mobile, and display higher plasticity in response to thermal variability than asexual counterparts. Discussion Thus, each form has consistent multiple adaptations to the ecological circumstances in the contrasting environments.

  5. Gonad establishment during asexual reproduction in the annelid Pristina leidyi.

    Science.gov (United States)

    Özpolat, B Duygu; Bely, Alexandra E

    2015-09-01

    Animals that can reproduce by both asexual agametic reproduction and sexual reproduction must transmit or re-establish their germ line post-embryonically. Although such a dual reproductive mode has evolved repeatedly among animals, how asexually produced individuals establish their germ line remains poorly understood in most groups. We investigated germ line development in the annelid Pristina leidyi, a species that typically reproduces asexually by paratomic fission, intercalating a new tail and head in the middle of the body followed by splitting. We found that in fissioning individuals, gonads occur in anterior segments in the anterior-most individual as well as in new heads forming within fission zones. Homologs of the germ line/multipotency genes piwi, vasa, and nanos are expressed in the gonads, as well as in proliferative tissues including the posterior growth zone, fission zone, and regeneration blastema. In fissioning animals, certain cells on the ventral nerve cord express a homolog of piwi, are abundant near fission zones, and sometimes make contact with gonads. Such cells are typically undetectable near the blastema and posterior growth zone. Time-lapse imaging provides direct evidence that cells on the ventral nerve cord migrate preferentially towards fission zones. Our findings indicate that gonads form routinely in fissioning individuals, that a population of piwi-positive cells on the ventral nerve cord is associated with fission and gonads, and that cells resembling these piwi-positive cells migrate along the ventral nerve cord. We suggest that the piwi-positive ventral cells are germ cells that transmit the germ line across asexually produced individuals via migration along the ventral nerve cord. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Female autonomy and fertility: an overview of the situation in South Asia.

    Science.gov (United States)

    1987-12-01

    The persistence of moderate to high fertility in many countries in the South Asian region can be traced to sociocultural factors that prevent women from translating their family size preferences into practice through conscious use of family planning. Female autonomuy -- the ability to obtain information and to use it as the basis for decision making -- is strongly influenced by factors such as kinship and marriage relationships, age, religion, the political system, and the division of labor between the sexes. The complete dependence of younger women on men and older women, deference to age, and lack of access to the outside world combine to make it difficult for South Asian women to practice fertility control. Early marriage increases their exposure to the risk of pregnancy even further. Since women in this region are taught that their own interests are subordinate to those of the family group, they are likely to sacrifice their own desire to regulate fertility. Confronted with social isolation and an insecure future, women turn to children as a potential source of security, especially sons. The forces of modernization have the potential to give South Asian women the autonomy they need to resist pronatalist pressures. Such forces include overall development of the locality, opportunities for education and employment, legal reforms, the presence of change agents, the availability of family planning clinics, and the adoption of innovations in the immediate environment.

  7. Evolution of complex asexual reproductive strategies in jellyfish

    DEFF Research Database (Denmark)

    Schnedler-Meyer, Nicolas Azaña; Pigolotti, Simone; Mariani, Patrizio

    2018-01-01

    Many living organisms in terrestrial and aquatic ecosystems rely on multiple reproductive strategies to reduce the risk of extinction in variable environments. Examples are provided by the polyp stage of several bloom-forming jellyfish species, which can reproduce asexually using different buddin...

  8. Maternal MEMI Promotes Female Meiosis II in Response to Fertilization in Caenorhabditis elegans.

    Science.gov (United States)

    Ataeian, Maryam; Tegha-Dunghu, Justus; Curtis, Donna G; Sykes, Ellen M E; Nozohourmehrabad, Ashkan; Bajaj, Megha; Cheung, Karen; Srayko, Martin

    2016-12-01

    In most animals, female meiosis completes only after fertilization. Sperm entry has been implicated in providing a signal for the initiation of the final meiotic processes; however, a maternal component required for this process has not been previously identified. We report the characterization of a novel family of three highly similar paralogs (memi-1, memi-2, memi-3) that encode oocyte-specific proteins. A hyper-morphic mutation memi-1(sb41) results in failure to exit female meiosis II properly; however, loss of all three paralogs results in a "skipped meiosis II" phenotype. Mutations that prevent fertilization, such as fer-1(hc1), also cause a skipped meiosis II phenotype, suggesting that the MEMI proteins represent a maternal component of a postfertilization signal that specifies the meiosis II program. MEMI proteins are degraded before mitosis and sensitive to ZYG-11, a substrate-specific adapter for cullin-based ubiquitin ligase activity, and the memi-1(sb41) mutation results in inappropriate persistence of the MEMI-1 protein into mitosis. Using an RNAi screen for suppressors of memi-1(sb41), we identified a sperm-specific PP1 phosphatase, GSP-3/4, as a putative sperm component of the MEMI pathway. We also found that MEMI and GSP-3/4 proteins can physically interact via co-immunoprecipitation. These results suggest that sperm-specific PP1 and maternal MEMI proteins act in the same pathway after fertilization to facilitate proper meiosis II and the transition into embryonic mitosis. Copyright © 2016 by the Genetics Society of America.

  9. The Effect of a First Child on Female Labor Supply: Evidence from Women Seeking Fertility Services

    Science.gov (United States)

    Cristia, Julian P.

    2008-01-01

    Estimating the causal effect of a first child on female labor supply is complicated by the endogeneity of fertility. This paper addresses this problem by focusing on a sample of women from the National Survey of Family Growth (NSFG) who sought help to become pregnant. After a certain period, only some of these women gave birth. Results using this…

  10. Does fertility status influence impulsivity and risk taking in human females? Adaptive influences on intertemporal choice and risky decision making.

    Science.gov (United States)

    Kaighobadi, Farnaz; Stevens, Jeffrey R

    2013-07-18

    Informed by the research on adaptive decision making in other animal species, this study investigated human females' intertemporal and risky choices across the ovulatory cycle. We tested the hypothesis that at peak fertility, women who are exposed to environments that signal availability of higher quality mates (by viewing images of attractive males), become more impulsive and risk-seeking in economic decision tasks. To test this, we collected intertemporal and risky choice measures before and after exposure to images of either attractive males or neutral landscapes both at peak and low fertility conditions. The results showed an interaction between women's fertility status and image type, such that women at peak fertility viewing images of attractive men chose the smaller, sooner monetary reward option less than women at peak fertility viewing neutral images. Neither fertility status nor image type influenced risky choice. Thus, though exposure to images of men altered intertemporal choices at peak fertility, this occurred in the opposite direction than predicted--i.e., women at peak fertility became less impulsive. Nevertheless, the results of the current study provide evidence for shifts in preferences over the ovulatory cycle and opens future research on economic decision making.

  11. Does Fertility Status Influence Impulsivity and Risk Taking in Human Females? Adaptive Influences on Intertemporal Choice and Risky Decision Making

    Directory of Open Access Journals (Sweden)

    Farnaz Kaighobadi

    2013-07-01

    Full Text Available Informed by the research on adaptive decision making in other animal species, this study investigated human females' intertemporal and risky choices across the ovulatory cycle. We tested the hypothesis that at peak fertility, women who are exposed to environments that signal availability of higher quality mates (by viewing images of attractive males, become more impulsive and risk-seeking in economic decision tasks. To test this, we collected intertemporal and risky choice measures before and after exposure to images of either attractive males or neutral landscapes both at peak and low fertility conditions. The results showed an interaction between women's fertility status and image type, such that women at peak fertility viewing images of attractive men chose the smaller, sooner monetary reward option less than women at peak fertility viewing neutral images. Neither fertility status nor image type influenced risky choice. Thus, though exposure to images of men altered intertemporal choices at peak fertility, this occurred in the opposite direction than predicted—i.e., women at peak fertility became less impulsive. Nevertheless, the results of the current study provide evidence for shifts in preferences over the ovulatory cycle and opens future research on economic decision making.

  12. Let us not be unfair to asexuals: their ephemerality may be explained by neutral models without invoking any evolutionary constraints of asexuality

    Czech Academy of Sciences Publication Activity Database

    Janko, Karel

    2014-01-01

    Roč. 68, č. 2 (2014), s. 569-576 ISSN 0014-3820 R&D Projects: GA ČR GA13-12580S Institutional support: RVO:67985904 Keywords : age of clones * asexuality * clonal turnover Subject RIV: EG - Zoology Impact factor: 4.612, year: 2014

  13. Hybrid asexuality as a primary postzygotic barrier between nascent species: on the interconnection between asexuality, hybridization and speciation

    Czech Academy of Sciences Publication Activity Database

    Janko, K.; Pačes, J.; Wilkinson-Herbots, H.; Costa, R. J.; Roslein, Jan; Drozd, P.; Iakovenko, N.; Rídl, J.; Hroudová, M.; Kočí, J.; Reifová, R.; Šlechtová, V.; Choleva, L.

    2018-01-01

    Roč. 27, č. 1 (2018), s. 248-263 ISSN 0962-1083 R&D Projects: GA ČR(CZ) GBP505/12/G112 Institutional support: RVO:68081766 Keywords : pairwise nucleotide differences * mitochondrial-dna variation * multilocus genotype data * reproductive isolation * maximum-likelihood * loaches cobitis * migration model * gene flow * phylogenetic constraints * coalescence time * balance hypothesis * coalescence * evolution of asexuality * hybridization * phylogeography * speciation Subject RIV: EG - Zoology Impact factor: 6.086, year: 2016

  14. Long-term effects of prenatal X ray on development and fertility of human females

    International Nuclear Information System (INIS)

    Meyer, M.B.; Tonascia, J.A.; Merz, T.

    1976-01-01

    This continuing epidemiologic study investigates possible effects of X-ray exposure during foetal life on the subsequent development and fertility of human females and on their offspring. The study population comprises 1458 females exposed in utero to maternal diagnostic X ray such as pelvimetry, and 1458 unexposed controls matched by hospital of birth, parity, race and birthdate (1947-1952). Phase I of the study showed a 10-15% increase in fertility in young exposed women, based on ascertainment of live births and foetal deaths registered in Baltimore City. This statistically significant difference (p=0.011) remained after adjustment for differences between exposed and control women in economic, social and medical factors. Phase II of the study, a direct follow-up of exposed control pairs of women now aged 22-28, continues to show more total pregnancies among exposed women. Exposed-in-utero women had 15% more total pregnancies than controls in 1960-1969, and 7% more in 1970-1975. Exposed and control women are similar in number of siblings, number of children wanted, contraceptive use, and frequency of therapeutic abortion. Other findings suggest possible exposed-control differences in growth, development and behaviour. Exposed women have completed fewer grades of school, have poorer general health, more menstrual problems, more of certain diseases and accidents, and are heavier for height than controls. (author)

  15. Beta-Thalassemia Major and Female Fertility: The Role of Iron and Iron-Induced Oxidative Stress

    Science.gov (United States)

    Roussou, Paraskevi; Tsagarakis, Nikolaos J.; Diamanti-Kandarakis, Evanthia

    2013-01-01

    Endocrine complications due to haemosiderosis are present in a significant number of patients with beta-thalassemia major (BTM) worldwide and often become barriers in their desire for parenthood. Thus, although spontaneous fertility can occur, the majority of females with BTM is infertile due to hypogonadotropic hypogonadism (HH) and need assisted reproductive techniques. Infertility in these women seems to be attributed to iron deposition and iron-induced oxidative stress (OS) in various endocrine organs, such as hypothalamus, pituitary, and female reproductive system, but also through the iron effect on other organs, such as liver and pancreas, contributing to the impaired metabolism of hormones and serum antioxidants. Nevertheless, the gonadal function of these patients is usually intact and fertility is usually retrievable. Meanwhile, a significant prooxidants/antioxidants imbalance with subsequent increased (OS) exists in patients with BTM, which is mainly caused by tissue injury due to overproduction of free radicals by secondary iron overload, but also due to alteration in serum trace elements and antioxidant enzymes. Not only using the appropriate antioxidants, essential trace elements, and minerals, but also regulating the advanced glycation end products, could probably reduce the extent of oxidative damage and related complications and retrieve BTM women's infertility. PMID:24396593

  16. Fertility preservation in females with malignant disease-1: causes, clinical needs and indications

    Directory of Open Access Journals (Sweden)

    Murat Sönmezer

    2009-09-01

    Full Text Available Cancer incidence is progressively increasing in parallel with an increase in the rate of cancer survivors with the help of advanced treatment modalities. By the year 2010, it is estimated that one in every 250 persons will have survived a childhood malignancy. The increased rates of survival bring about complications related to reproductive health. Cytotoxic treatments due to chemo- and radiotherapy or bone marrow transplantation suppress or irreversibly harm not only female ovarian reserve but also male testicular sperm production. In this review, cryopreservation of gametes and gonads with fertility preservation options and indications prior to cancer treatments are discussed.

  17. Ontology for the asexual development and anatomy of the colonial chordate Botryllus schlosseri.

    Directory of Open Access Journals (Sweden)

    Lucia Manni

    Full Text Available Ontologies provide an important resource to integrate information. For developmental biology and comparative anatomy studies, ontologies of a species are used to formalize and annotate data that are related to anatomical structures, their lineage and timing of development. Here, we have constructed the first ontology for anatomy and asexual development (blastogenesis of a bilaterian, the colonial tunicate Botryllus schlosseri. Tunicates, like Botryllus schlosseri, are non-vertebrates and the only chordate taxon species that reproduce both sexually and asexually. Their tadpole larval stage possesses structures characteristic of all chordates, i.e. a notochord, a dorsal neural tube, and gill slits. Larvae settle and metamorphose into individuals that are either solitary or colonial. The latter reproduce both sexually and asexually and these two reproductive modes lead to essentially the same adult body plan. The Botryllus schlosseri Ontology of Development and Anatomy (BODA will facilitate the comparison between both types of development. BODA uses the rules defined by the Open Biomedical Ontologies Foundry. It is based on studies that investigate the anatomy, blastogenesis and regeneration of this organism. BODA features allow the users to easily search and identify anatomical structures in the colony, to define the developmental stage, and to follow the morphogenetic events of a tissue and/or organ of interest throughout asexual development. We invite the scientific community to use this resource as a reference for the anatomy and developmental ontology of B. schlosseri and encourage recommendations for updates and improvements.

  18. Public goods dilemma in asexual ant societies

    OpenAIRE

    Dobata, Shigeto; Tsuji, Kazuki

    2013-01-01

    This study reports experimental evidence for the “public goods dilemma” between cooperators and cheaters in an asexual ant society, in which cheating is always more rewarding for individuals but cooperation at the cost of individual fitness leads to better performance of groups. Although this dilemma provides the basic principle of social evolution, its experimental demonstration with underlying genetics and fitness evaluation for both cooperators and cheaters still lacks in societies other t...

  19. Plant Growth-Promoting Rhizobacteria Stimulate Vegetative Growth and Asexual Reproduction of Kalanchoe daigremontiana.

    Science.gov (United States)

    Park, Yong-Soon; Park, Kyungseok; Kloepper, Joseph W; Ryu, Choong-Min

    2015-09-01

    Certain bacterial species associate with plant roots in soil. The plant growth-promoting rhizobacteria (PGPR) stimulate plant growth and yield in greenhouse and field. Here, we examined whether application of known bacilli PGPR strains stimulated growth and asexual reproduction in the succulent plant Kalanchoe daigremontiana. Four PGPR strains B. amyloliquefaciens IN937a, B. cereus BS107, B. pumilus INR7, and B. subtilis GB03 were applied to young plantlets by soil-drenching, and plant growth and development was monitored for three months. Aerial growth was significantly stimulated in PGPR-inoculated plants, which was observed as increases in plant height, shoot weight, and stem width. The stimulated growth influenced plant development by increasing the total number of leaves per plant. Treatment with bacilli also increased the total root biomass compared with that of control plants, and led to a 2-fold increase in asexual reproduction and plantlet formation on the leaf. Collectively, our results firstly demonstrate that Bacillus spp. promote vegetative development of K. daigremontiana, and the enhanced growth stimulates asexual reproduction and plantlet formation.

  20. Plant Growth-Promoting Rhizobacteria Stimulate Vegetative Growth and Asexual Reproduction of Kalanchoe daigremontiana

    Directory of Open Access Journals (Sweden)

    Yong-Soon Park

    2015-09-01

    Full Text Available Certain bacterial species associate with plant roots in soil. The plant growth-promoting rhizobacteria (PGPR stimulate plant growth and yield in greenhouse and field. Here, we examined whether application of known bacilli PGPR strains stimulated growth and asexual reproduction in the succulent plant Kalanchoe daigremontiana. Four PGPR strains B. amyloliquefaciens IN937a, B. cereus BS107, B. pumilus INR7, and B. subtilis GB03 were applied to young plantlets by soil-drenching, and plant growth and development was monitored for three months. Aerial growth was significantly stimulated in PGPR-inoculated plants, which was observed as increases in plant height, shoot weight, and stem width. The stimulated growth influenced plant development by increasing the total number of leaves per plant. Treatment with bacilli also increased the total root biomass compared with that of control plants, and led to a 2-fold increase in asexual reproduction and plantlet formation on the leaf. Collectively, our results firstly demonstrate that Bacillus spp. promote vegetative development of K. daigremontiana, and the enhanced growth stimulates asexual reproduction and plantlet formation.

  1. Hybrid asexuality as a primary postzygotic barrier between nascent species: On the interconnection between asexuality, hybridization and speciation

    Czech Academy of Sciences Publication Activity Database

    Janko, Karel; Pačes, Jan; Wilkinson-Herbots, H.; Costa, R. J.; Roslein, Jan; Drozd, P.; Iakovenko, Nataliia; Rídl, J.; Hroudová, M.; Kočí, Jan; Reifová, R.; Šlechtová, Věra; Choleva, Lukáš

    2018-01-01

    Roč. 27, č. 1 (2018), s. 248-263 ISSN 0962-1083 R&D Projects: GA AV ČR KJB600450902; GA MŠk EF15_003/0000460; GA ČR GA13-12580S; GA ČR GA206/09/1298; GA ČR GAP506/10/1155; GA ČR GJ15-19947Y Institutional support: RVO:67985904 Keywords : balance hypothesis * coalescence * ecolution of asexuality * hybridization Subject RIV: EG - Zoology OBOR OECD: Zoology Impact factor: 6.086, year: 2016

  2. Increased progesterone production in cumulus-oocyte complexes of female mice sired by males with the Y-chromosome long arm deletion and its potential influence on fertilization efficiency.

    Science.gov (United States)

    Kotarska, Katarzyna; Galas, Jerzy; Przybyło, Małgorzata; Bilińska, Barbara; Styrna, Józefa

    2015-02-01

    It was revealed previously that B10.BR(Y(del)) females sired by males with the Y-chromosome long arm deletion differ from genetically identical B10.BR females sired by males with the intact Y chromosome. This is interpreted as a result of different epigenetic information which females of both groups inherit from their fathers. In the following study, we show that cumulus-oocyte complexes ovulated by B10.BR(Y(del)) females synthesize increased amounts of progesterone, which is important sperm stimulator. Because their extracellular matrix is excessively firm, the increased progesterone secretion belongs presumably to factors that compensate this feature enabling unchanged fertilization ratios. Described compensatory mechanism can act only on sperm of high quality, presenting proper receptors. Indeed, low proportion of sperm of Y(del) males that poorly fertilize B10.BR(Y(del)) oocytes demonstrates positive staining of membrane progesterone receptors. This proportion is significantly higher for sperm of control males that fertilize B10.BR(Y(del)) and B10.BR oocytes with the same efficiency. © The Author(s) 2014.

  3. The Trojan Female Technique for pest control: a candidate mitochondrial mutation confers low male fertility across diverse nuclear backgrounds in Drosophila melanogaster.

    Science.gov (United States)

    Dowling, Damian K; Tompkins, Daniel M; Gemmell, Neil J

    2015-10-01

    Pest species represent a major ongoing threat to global biodiversity. Effective management approaches are required that regulate pest numbers, while minimizing collateral damage to nontarget species. The Trojan Female Technique (TFT) was recently proposed as a prospective approach to biological pest control. The TFT draws on the evolutionary hypothesis that maternally inherited mitochondrial genomes are prone to the accumulation of male, but not female, harming mutations. These mutations could be harnessed to provide trans-generational fertility-based control of pest species. A candidate TFT mutation was recently described in the fruit fly, Drosophila melanogaster, which confers male-only sterility in the specific isogenic nuclear background in which it is maintained. However, applicability of the TFT relies on mitochondrial mutations whose male-sterilizing effects are general across nuclear genomic contexts. We test this assumption, expressing the candidate TFT-mutation bearing haplotype alongside a range of nuclear backgrounds and comparing its fertility in males, relative to that of control haplotypes. We document consistently lower fertility for males harbouring the TFT mutation, in both competitive and noncompetitive mating contexts, across all nuclear backgrounds screened. This indicates that TFT mutations conferring reduced male fertility can segregate within populations and could be harnessed to facilitate this novel form of pest control.

  4. Female married illiteracy as the most important continual determinant of total fertility rate among districts of Empowered Action Group States of India: Evidence from Annual Health Survey 2011-12.

    Science.gov (United States)

    Kumar, Rajesh; Dogra, Vishal; Rani, Khushbu; Sahu, Kanti

    2017-01-01

    District level determinants of total fertility rate in Empowered Action Group states of India can help in ongoing population stabilization programs in India. Present study intends to assess the role of district level determinants in predicting total fertility rate among districts of the Empowered Action Group states of India. Data from Annual Health Survey (2011-12) was analysed using STATA and R software packages. Multiple linear regression models were built and evaluated using Akaike Information Criterion. For further understanding, recursive partitioning was used to prepare a regression tree. Female married illiteracy positively associated with total fertility rate and explained more than half (53%) of variance. Under multiple linear regression model, married illiteracy, infant mortality rate, Ante natal care registration, household size, median age of live birth and sex ratio explained 70% of total variance in total fertility rate. In regression tree, female married illiteracy was the root node and splits at 42% determined TFR illiteracy with splits at 23% to determine TFR illiteracy is one of the most important determinants explaining total fertility rate among the districts of an Empowered Action Group states. Focus on female literacy is required to stabilize the population growth in long run.

  5. Modelling female fertility traits in beef cattle using linear and non-linear models.

    Science.gov (United States)

    Naya, H; Peñagaricano, F; Urioste, J I

    2017-06-01

    Female fertility traits are key components of the profitability of beef cattle production. However, these traits are difficult and expensive to measure, particularly under extensive pastoral conditions, and consequently, fertility records are in general scarce and somehow incomplete. Moreover, fertility traits are usually dominated by the effects of herd-year environment, and it is generally assumed that relatively small margins are kept for genetic improvement. New ways of modelling genetic variation in these traits are needed. Inspired in the methodological developments made by Prof. Daniel Gianola and co-workers, we assayed linear (Gaussian), Poisson, probit (threshold), censored Poisson and censored Gaussian models to three different kinds of endpoints, namely calving success (CS), number of days from first calving (CD) and number of failed oestrus (FE). For models involving FE and CS, non-linear models overperformed their linear counterparts. For models derived from CD, linear versions displayed better adjustment than the non-linear counterparts. Non-linear models showed consistently higher estimates of heritability and repeatability in all cases (h 2  linear models; h 2  > 0.23 and r > 0.24, for non-linear models). While additive and permanent environment effects showed highly favourable correlations between all models (>0.789), consistency in selecting the 10% best sires showed important differences, mainly amongst the considered endpoints (FE, CS and CD). In consequence, endpoints should be considered as modelling different underlying genetic effects, with linear models more appropriate to describe CD and non-linear models better for FE and CS. © 2017 Blackwell Verlag GmbH.

  6. The roles of sexual and asexual reproduction in the origin and dissemination of strains causing fungal infectious disease outbreaks.

    Science.gov (United States)

    Ashu, Eta Ebasi; Xu, Jianping

    2015-12-01

    Sexual reproduction commonly refers to the reproductive process in which genomes from two sources are combined into a single cell through mating and then the zygote genomes are partitioned to progeny cells through meiosis. Reproduction in the absence of mating and meiosis is referred to as asexual or clonal reproduction. One major advantage of sexual reproduction is that it generates genetic variation among progeny which may allow for faster adaptation of the population to novel and/or stressful environments. However, adaptation to stressful or new environments can still occur through mutation, in the absence of sex. In this review, we analyzed the relative contributions of sexual and asexual reproduction in the origin and spread of strains causing fungal infectious diseases outbreaks. The necessity of sex and the ability of asexual fungi to initiate outbreaks are discussed. We propose a framework that relates the modes of reproduction to the origin and propagation of fungal disease outbreaks. Our analyses suggest that both sexual and asexual reproduction can play critical roles in the origin of outbreak strains and that the rapid spread of outbreak strains is often accomplished through asexual expansion. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Is meiosis a fundamental cause of inviability among sexual and asexual plants and animals?

    Science.gov (United States)

    Levitis, Daniel A; Zimmerman, Kolea; Pringle, Anne

    2017-08-16

    Differences in viability between asexually and sexually generated offspring strongly influence the selective advantage and therefore the prevalence of sexual reproduction (sex). However, no general principle predicts when sexual offspring will be more viable than asexual offspring. We hypothesize that when any kind of reproduction is based on a more complex cellular process, it will encompass more potential failure points, and therefore lower offspring viability. Asexual reproduction (asex) can be simpler than sex, when offspring are generated using only mitosis. However, when asex includes meiosis and meiotic restitution, gamete production is more complex than in sex. We test our hypothesis by comparing the viability of asexual and closely related sexual offspring across a wide range of plants and animals, and demonstrate that meiotic asex does result in lower viability than sex; without meiosis, asex is mechanistically simple and provides higher viability than sex. This phylogenetically robust pattern is supported in 42 of 44 comparisons drawn from diverse plants and animals, and is not explained by the other variables included in our model. Other mechanisms may impact viability, such as effects of reproductive mode on heterozygosity and subsequent viability, but we propose the complexity of cellular processes of reproduction, particularly meiosis, as a fundamental cause of early developmental failure and mortality. Meiosis, the leading cause of inviability in humans, emerges as a likely explanation of offspring inviability among diverse eukaryotes. © 2017 The Author(s).

  8. On the age-specific correlation between fertility and female employment: Heterogeneity over space and time in OECD countries

    Directory of Open Access Journals (Sweden)

    Uta Brehm

    2015-03-01

    Full Text Available Background: Though there has been profound research on the curious change in correlation between total fertility rate (TFR and female labor force participation (FLP in the mid-1980s, aspects of the compositional character of age-specific effects and the nature of countries' heterogeneity have been neglected. Objective: The present paper aims to contribute to filling this gap by analyzing annual total fertility rates and their equivalents for four age groups between 20 and 39 years as well as the respective lagged FLP from 17 OECD countries between 1985 and 2010. Methods: Random Intercept and Random Coefficient Models are applied, allowing us to assess both effects and country heterogeneity in slopes and intercepts. Results: The analyses reveal that the development of the correlation between FLP and TFR after 1985 is comprised of very different relations between age-specific fertility and labor participation. The youngest group's situation is determined by a decrease in both fertility and FLP, while countries' effects differ increasingly. The oldest women's fertility decisions seem to be detached from labor market influences, though country variation is high. Women in their late 20s and early 30s, in contrast, appear to be most affected by the incompatibility of childbearing and gainful employment. Though these effects seem to have overcome their low points during the mid-1990s, only women in their early 30s show country-convergence. Conclusions: The results highlight the fact that total and age-specific fertility behavior, FLP-effects and country variances are distinct concepts that add considerably to the broad understanding of the correlation between fertility and FLP.

  9. Female married illiteracy as the most important continual determinant of total fertility rate among districts of Empowered Action Group States of India: Evidence from Annual Health Survey 2011–12

    Directory of Open Access Journals (Sweden)

    Rajesh Kumar

    2017-01-01

    Full Text Available Background: District level determinants of total fertility rate in Empowered Action Group states of India can help in ongoing population stabilization programs in India. Objective: Present study intends to assess the role of district level determinants in predicting total fertility rate among districts of the Empowered Action Group states of India. Material and Methods: Data from Annual Health Survey (2011-12 was analysed using STATA and R software packages. Multiple linear regression models were built and evaluated using Akaike Information Criterion. For further understanding, recursive partitioning was used to prepare a regression tree. Results: Female married illiteracy positively associated with total fertility rate and explained more than half (53% of variance. Under multiple linear regression model, married illiteracy, infant mortality rate, Ante natal care registration, household size, median age of live birth and sex ratio explained 70% of total variance in total fertility rate. In regression tree, female married illiteracy was the root node and splits at 42% determined TFR = 2.7. The next left side branch was again married illiteracy with splits at 23% to determine TFR = 2.1. Conclusion: We conclude that female married illiteracy is one of the most important determinants explaining total fertility rate among the districts of an Empowered Action Group states. Focus on female literacy is required to stabilize the population growth in long run.

  10. Female age-related fertility decline. Committee Opinion No. 589.

    Science.gov (United States)

    2014-03-01

    The fecundity of women decreases gradually but significantly beginning approximately at age 32 years and decreases more rapidly after age 37 years. Education and enhanced awareness of the effect of age on fertility are essential in counseling the patient who desires pregnancy. Given the anticipated age-related decline in fertility, the increased incidence of disorders that impair fertility, and the higher risk of pregnancy loss, women older than 35 years should receive an expedited evaluation and undergo treatment after 6 months of failed attempts to conceive or earlier, if clinically indicated. In women older than 40 years, more immediate evaluation and treatment are warranted. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  11. Laboratory synthesis of an independently reproducing vertebrate species.

    Science.gov (United States)

    Lutes, Aracely A; Baumann, Diana P; Neaves, William B; Baumann, Peter

    2011-06-14

    Speciation in animals commonly involves an extrinsic barrier to genetic exchange followed by the accumulation of sufficient genetic variation to impede subsequent productive interbreeding. All-female species of whiptail lizards, which originated by interspecific hybridization between sexual progenitors, are an exception to this rule. Here, the arising species instantaneously acquires a novel genotype combining distinctive alleles from two different species, and reproduction by parthenogenesis constitutes an effective intrinsic barrier to genetic exchange. Fertilization of diploid parthenogenetic females by males of sexual species has produced several triploid species, but these instantaneous speciation events have neither been observed in nature nor have they been reconstituted in the laboratory. Here we report the generation of four self-sustaining clonal lineages of a tetraploid species resulting from fertilization of triploid oocytes from a parthenogenetic Aspidoscelis exsanguis with haploid sperm from Aspidoscelis inornata. Molecular and cytological analysis confirmed the genetic identity of the hybrids and revealed that the females retain the capability of parthenogenetic reproduction characteristic of their triploid mothers. The tetraploid females have established self-perpetuating clonal lineages which are now in the third generation. Our results confirm the hypothesis that secondary hybridization events can lead to asexual lineages of increased ploidy when favorable combinations of parental genomes are assembled. We anticipate that these animals will be a critical tool in understanding the mechanisms underlying the origin and subsequent evolution of asexual amniotes.

  12. [Artistic representation of the female breast as an attribute of femininity and fertility and also the origin of life force and wisdom].

    Science.gov (United States)

    Kirchhoff, H

    1990-03-01

    The artistic representation of the female breasts is based upon two totally independent concepts, which are different in their expression. On the one hand, the figure, clasping her hands around her breasts, stands for womanliness and fertility. On the other hand, the act of voiding milk or water, symbolizes donation of or wisdom. These two functions of the female breasts are a large number of illustrations.

  13. Cancer and fertility: strategies to preserve fertility.

    Science.gov (United States)

    Diedrich, K; Fauser, B C J M; Devroey, P

    2011-03-01

    Fertility preservation is a key component of cancer management in young people. The Fourth Evian Annual Reproduction Workshop Meeting was held in April 2009 to discuss cancer and fertility in young adults. Specialists in oncology, assisted reproduction, embryology and clinical genetics presented published data and ongoing research on cancer and fertility, with particular focus on strategies to preserve fertility. This report is based on the expert presentations and group discussions, supplemented with publications from literature searches and the authors' knowledge. Fertility preservation should be considered for all young people undergoing potentially gonadotoxic cancer treatment. A variety of options are required to facilitate safe and effective fertility preservation for individual patients. Sperm banking is a simple and low-cost intervention. Embryo cryopreservation is the only established method of female fertility preservation. Oocyte cryopreservation offers a useful option for women without a male partner. Emergency ovarian stimulation and cryopreservation of ovarian tissue (followed by tissue transplantation or in-vitro maturation of oocytes) are experimental techniques for women who require urgent cancer treatment. Further prospective studies are required to validate cryopreservation of oocytes and ovarian tissue, in-vitro maturation of oocytes and new vitrification techniques and to identify any long-term sequelae of slow freezing of embryos. Copyright © 2010 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  14. The first multi-gene phylogeny of the Macrostomorpha sheds light on the evolution of sexual and asexual reproduction in basal Platyhelminthes.

    Science.gov (United States)

    Janssen, Toon; Vizoso, Dita B; Schulte, Gregor; Littlewood, D Timothy J; Waeschenbach, Andrea; Schärer, Lukas

    2015-11-01

    The Macrostomorpha-an early branching and species-rich clade of free-living flatworms-is attracting interest because it contains Macrostomum lignano, a versatile model organism increasingly used in evolutionary, developmental, and molecular biology. We elucidate the macrostomorphan molecular phylogeny inferred from both nuclear (18S and 28S rDNA) and mitochondrial (16S rDNA and COI) marker genes from 40 representatives. Although our phylogeny does not recover the Macrostomorpha as a statistically supported monophyletic grouping, it (i) confirms many taxa previously proposed based on morphological evidence, (ii) permits the first placement of many families and genera, and (iii) reveals a number of unexpected placements. Specifically, Myozona and Bradynectes are outside the three classic families (Macrostomidae, Microstomidae and Dolichomacrostomidae) and the asexually fissioning Myomacrostomum belongs to a new subfamily, the Myozonariinae nov. subfam. (Dolichomacrostomidae), rather than diverging early. While this represents the first evidence for asexuality among the Dolichomacrostomidae, we show that fissioning also occurs in another Myozonariinae, Myozonaria fissipara nov. sp. Together with the placement of the (also fissioning) Microstomidae, namely as the sister taxon of Dolichomacrostomidae, this suggests that fissioning is not basal within the Macrostomorpha, but rather restricted to the new taxon Dolichomicrostomida (Dolichomacrostomidae+Microstomidae). Furthermore, our phylogeny allows new insights into the evolution of the reproductive system, as ancestral state reconstructions reveal convergent evolution of gonads, and male and female genitalia. Finally, the convergent evolution of sperm storage organs in the female genitalia appears to be linked to the widespread occurrence of hypodermic insemination among the Macrostomorpha. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Rac1 is dispensable for oocyte maturation and female fertility in vivo.

    Science.gov (United States)

    Hao, Jian-Xiu; Meng, Tie-Gang; Fan, Li-Hua; Yao, Yuan-Qing

    2017-01-01

    Oocyte maturation, the important process to produce female haploid gamete, accompanies with polarity establishment and highly asymmetric cell division to emit minor polar body within little cytoplasm. Microfilaments play central roles in polarity establishment and asymmetric cell division. Several actin regulators like WASP protein family as well as small GTPases function in microfilament dynamics, involving the process. Rac1, one member of RhoGTPases, has been reported to regulate the polarity and asymmetric cell division in mouse oocytes in vitro. The physiological role of Rac1 in mouse oocyte remains unknown. By conditional knockout technology, we specifically deleted Rac1 gene in mouse oocyte, and found that Rac1 deletion exerted little effect on mouse oocyte maturation including polarity establishment and asymmetric division, and the mutant mice showed normal fertility.

  16. Multivariate Cholesky models of human female fertility patterns in the NLSY.

    Science.gov (United States)

    Rodgers, Joseph Lee; Bard, David E; Miller, Warren B

    2007-03-01

    Substantial evidence now exists that variables measuring or correlated with human fertility outcomes have a heritable component. In this study, we define a series of age-sequenced fertility variables, and fit multivariate models to account for underlying shared genetic and environmental sources of variance. We make predictions based on a theory developed by Udry [(1996) Biosocial models of low-fertility societies. In: Casterline, JB, Lee RD, Foote KA (eds) Fertility in the United States: new patterns, new theories. The Population Council, New York] suggesting that biological/genetic motivations can be more easily realized and measured in settings in which fertility choices are available. Udry's theory, along with principles from molecular genetics and certain tenets of life history theory, allow us to make specific predictions about biometrical patterns across age. Consistent with predictions, our results suggest that there are different sources of genetic influence on fertility variance at early compared to later ages, but that there is only one source of shared environmental influence that occurs at early ages. These patterns are suggestive of the types of gene-gene and gene-environment interactions for which we must account to better understand individual differences in fertility outcomes.

  17. Fertility information needs and concerns post-treatment contribute to lowered quality of life among young adult female cancer survivors.

    Science.gov (United States)

    Benedict, Catherine; Thom, Bridgette; Friedman, Danielle N; Pottenger, Elaine; Raghunathan, Nirupa; Kelvin, Joanne F

    2018-07-01

    Cancer treatment may lead to premature menopause and infertility. Young adult female cancer survivors (YAFCS) are often concerned about their fertility and future family-building options, but research is limited on how concerns may affect more general quality of life (QOL) domains. This study examined how fertility factors relate to QOL among YAFCS who received gonadotoxic therapy. A national sample of YAFCS completed an online, anonymous survey. The survey included investigator-designed questions about perceived fertility information needs (five items; Cronbach's α = .83) and general QOL (four items; α = .89), the Reproductive Concerns after Cancer Scale (RCACS) and Decisional Conflict Scale (DCS). Analyses included Pearson's correlation, t tests, and stepwise regression. Participants (N = 314) were an average of 30 years old (SD = 4.1) and 5 years (SD = 5.4) post-treatment; 31% reported being infertile and 19% had undergone fertility preservation (FP). Overall, QOL was relatively high (M = 7.3, SD = 1.9, range 0-10) and did not vary by fertility status (t[272] = .743, p = .46), prior FP (t[273] = .53, p = .55) or sociodemographic/clinical factors (p's > .05) except socioeconomic indicators (p's < .05).In separate models, greater unmet fertility information needs (β = - .19, p = .004) and, among fertile women, greater reproductive concerns (β = - .26, p = .001) related to lower QOL. Among fertile women without prior FP, greater decisional distress about future FP related to lower QOL (β = - .19, p = .03). These preliminary findings suggest that unaddressed fertility information needs, concerns, and decision distress may affect general QOL among post-treatment YAFCS who hope to have children in the future. Future work should identify ways to optimally incorporate fertility counseling and support resources into survivorship care programs, including referrals to reproductive

  18. Fertility prognosis for infertile couples

    DEFF Research Database (Denmark)

    Bostofte, E; Bagger, P; Michael, A

    1993-01-01

    OBJECTIVE: To develop a fertility prognosis model for infertile couples. DESIGN: Prospective follow-up study. PARTICIPANTS: In the period November 30, 1977 to June 1, 1985, 321 consecutive couples were investigated for infertility at Hvidovre University Hospital. Investigation of the female...... MEASURE: The Cox regression model was used to predict the time required to conceive based on informations provided by fertility investigations. RESULTS: Three of 16 prognostic variables (the period of infertility, the female infertility factor, and the P-test) possess significant prognostic information...

  19. Female married illiteracy as the most important continual determinant of total fertility rate among districts of Empowered Action Group States of India: Evidence from Annual Health Survey 2011–12

    Science.gov (United States)

    Kumar, Rajesh; Dogra, Vishal; Rani, Khushbu; Sahu, Kanti

    2017-01-01

    Background: District level determinants of total fertility rate in Empowered Action Group states of India can help in ongoing population stabilization programs in India. Objective: Present study intends to assess the role of district level determinants in predicting total fertility rate among districts of the Empowered Action Group states of India. Material and Methods: Data from Annual Health Survey (2011-12) was analysed using STATA and R software packages. Multiple linear regression models were built and evaluated using Akaike Information Criterion. For further understanding, recursive partitioning was used to prepare a regression tree. Results: Female married illiteracy positively associated with total fertility rate and explained more than half (53%) of variance. Under multiple linear regression model, married illiteracy, infant mortality rate, Ante natal care registration, household size, median age of live birth and sex ratio explained 70% of total variance in total fertility rate. In regression tree, female married illiteracy was the root node and splits at 42% determined TFR illiteracy with splits at 23% to determine TFR illiteracy is one of the most important determinants explaining total fertility rate among the districts of an Empowered Action Group states. Focus on female literacy is required to stabilize the population growth in long run. PMID:29416999

  20. Implementation strategy for achieving replacement level fertility.

    Science.gov (United States)

    1993-01-01

    The recommendation of the Bali Declaration on Population and Sustainable Development at the ESCAP regional conference was to adopt strategies for attaining replacement-level fertility of 2.1 or 2.2 children by 2010. East Asian countries, except Mongolia and the Democratic People's Republic of Korea, and the Southeast Asian countries Singapore and Thailand have already reached replacement-level fertility. Most larger Oceanic countries have also done so. Only South Asian Sri Lanka and southern India have attained replacement level. The following conditions slow or hinder the goal, but they do not provide an "absolute" barrier to fertility decline: social welfare schemes and old age security, son preference, lack of government family planning, poverty, relatively high mortality, low status of women, and education status. Theories of demographic transition have postulated that economic and social development initially brings a decline in mortality, and later brings a decline in fertility; and high fertility was an adaptation to high mortality. Policy gets caught in the lag between mortality and fertility decline. Eventually the cultural motives for high fertility are undercut by social and economic development. Although the generalization that economic growth slows fertility is true for South Asia, the correlation is uneven. Forceful government-sponsored family planning programs in Bangladesh and China may lead the way to strategies for decline in ESCAP region. A Thailand study suggested important factors were fundamental social change, the increased cost of children, cultural acceptance of birth control, a latent demand for fertility control, and government efforts in family planning. ESCAP countries have in common relatively high morality and inadequate public health programs, patriarchal structures, and limited female autonomy, poverty and landlessness, lack of community cohesiveness, and inadequate family planning programs. Weaknesses in programs are attributed to

  1. Hybrid asexuality as a primary postzygotic barrier between nascent species: On the interconnection between asexuality, hybridization and speciation

    Czech Academy of Sciences Publication Activity Database

    Janko, K.; Pačes, Jan; Wilkinson-Herbots, H.; Costa, R. J.; Roslein, J.; Drozd, P.; Iakovenko, N.; Rídl, Jakub; Hroudová, Miluše; Kočí, J.; Reifová, R.; Šlechtová, V.; Choleva, L.

    2018-01-01

    Roč. 27, č. 1 (2018), s. 248-263 ISSN 0962-1083 R&D Projects: GA AV ČR KJB600450902; GA MŠk(CZ) LM2015047; GA ČR GA13-12580S; GA ČR GA206/09/1298; GA ČR GAP506/10/1155; GA ČR GJ15-19947Y; GA MŠk EF15_003/0000460 Institutional support: RVO:68378050 ; RVO:67985904 Keywords : balance hypothesis * coalescence * evolution of asexuality * hybridization * phylogeography * speciation Subject RIV: CE - Biochemistry OBOR OECD: Genetics and heredity (medical genetics to be 3) Impact factor: 6.086, year: 2016

  2. Immigrant fertility in Sweden, 2000-2011: A descriptive note

    Directory of Open Access Journals (Sweden)

    Lotta Persson

    2014-03-01

    Full Text Available Background: Modern Scandinavian population registers provide excellent data sources that allow a user to quickly gain an impression of the level of fertility and its structure across subpopulations. This may also allow the analyst to check a feature of the much-cited disruption hypothesis, at least in part. Objective: The purpose of this note is to exploit this potential to give an overview of the structure of recent total fertility after immigration to Sweden from various groups of sending countries, separately for males and females. In the process we demonstrate to what extent the post-migration fertility compensation which is part of the fertility disruption hypothesis is fulfilled in our study population. Due to the nature of our data we have refrained from studying fertility before migration. Methods: Based on data from a combination of two Swedish administrative registers (the Historic Population Register and the Multi-Generation Register that cover both men and women in the entire population for the years 2000-2011, we compute and plot TFR-like age-cumulated fertility levels, specific for years since immigration, for six groups of sending countries, separately for men and women. Results: We find that the post-migration fertility compensation specified as part of the fertility disruption hypothesis is visibly confirmed in our Swedish study population for female European immigrants from non-EU countries and for female immigrants from non-European countries with a low or medium UN Human Development Index, but not so for other female immigrants, i.e. not for those who come from a Nordic country or from a non-Nordic EU country, and not for female immigrants from a non-European country with a high Human Development Index, including the United States. We find mild but less conclusive evidence for the same feature for males. Conclusions: This shows that at least as far as post-migration fertility compensation is concerned, the disruption

  3. Male and female experiences of having fertility matters raised alongside a cancer diagnosis during the teenage and young adult years.

    Science.gov (United States)

    Crawshaw, M A; Glaser, A W; Hale, J P; Sloper, P

    2009-07-01

    Discussion and management of potential reproductive health sequelae of adolescent cancer are essential and challenging components of care for the multidisciplinary team. Despite this, research has been limited to specific experiences (e.g. sperm banking) or fertility-related concerns of adult survivors. This grounded theory study of 38 male and female survivors of adolescent cancer aged 16-30 years drew on in-depth single interviews to map the range of experiences of being advised that treatment might affect fertility. Strong support for being told at around diagnosis was found regardless of gender, age, incapacity or availability of fertility preservation services. Age and life stage appeared less significant for impact than the perceived level of threat to personal and social well-being. Women were more likely to achieve lower levels of comprehension about the physiological impact, to report later distress from lack of fertility preservation services and to revisit more frequently those decisions made by the few offered fertility preservation. Men found decision making about sperm banking straightforward on the whole and reported satisfaction with having the choice regardless of outcome. Findings suggest that young people can cope with this information alongside diagnosis especially when professional and parental support is proportionate to the particular impact on them.

  4. Factors associated with the receipt of fertility preservation services along the decision-making pathway in young Canadian female cancer patients.

    Science.gov (United States)

    Yee, Samantha

    2016-02-01

    This study investigated the factors associated with the receipt of fertility preservation (FP) services along the decision-making pathway in young Canadian female cancer patients. The roles of the oncologists were examined. A total of 188 women who were diagnosed with cancer between the ages of 18-39 after the year 2000 and had finished active cancer treatment by the time of the survey (2012-2013) participated in the study. Logistic regression models and Pearson χ (2) tests were used for analyses. The mean ages of participants at diagnosis and at survey time were 30.2 (SD = 3.7) and 33.9 (SD = 5.9). One quarter (n = 45, 23.9 %) did not recall having a fertility discussion with their oncologists. Of the three quarters who had a fertility discussion (n = 143, 76.1 %), discussions were equally initiated by oncologists (n = 71) and patients (n = 72). Of the 49 women (26 %) who consulted a fertility specialist, 17 (9 %) underwent a FP procedure. Fertility concern at diagnosis was the driving force of the receipt of FP services at all decision points. Our findings suggest that not only was the proactive approach of oncologists in initiating a fertility discussion important, the quality of the discussion was equally critical in the decision-making pathway. Oncologists play a pivotal role in the provision of fertility services in that they are not only gate keepers, knowledge brokers, and referral initiators of FP consultation, but also they are catalysts in supporting cancer patients making important FP decision in conjunction with the consultation provided by a fertility specialist.

  5. Asexual Reproduction Does Not Apparently Increase the Rate of Chromosomal Evolution: Karyotype Stability in Diploid and Triploid Clonal Hybrid Fish (Cobitis, Cypriniformes, Teleostei).

    Science.gov (United States)

    Majtánová, Zuzana; Choleva, Lukáš; Symonová, Radka; Ráb, Petr; Kotusz, Jan; Pekárik, Ladislav; Janko, Karel

    2016-01-01

    Interspecific hybridization, polyploidization and transitions from sexuality to asexuality considerably affect organismal genomes. Especially the last mentioned process has been assumed to play a significant role in the initiation of chromosomal rearrangements, causing increased rates of karyotype evolution. We used cytogenetic analysis and molecular dating of cladogenetic events to compare the rate of changes of chromosome morphology and karyotype in asexually and sexually reproducing counterparts in European spined loach fish (Cobitis). We studied metaphases of three sexually reproducing species and their diploid and polyploid hybrid clones of different age of origin. The material includes artificial F1 hybrid strains, representatives of lineage originated in Holocene epoch, and also individuals of an oldest known age to date (roughly 0.37 MYA). Thereafter we applied GISH technique as a marker to differentiate parental chromosomal sets in hybrids. Although the sexual species accumulated remarkable chromosomal rearrangements after their speciation, we observed no differences in chromosome numbers and/or morphology among karyotypes of asexual hybrids. These hybrids possess chromosome sets originating from respective parental species with no cytogenetically detectable recombinations, suggesting their integrity even in a long term. The switch to asexual reproduction thus did not provoke any significant acceleration of the rate of chromosomal evolution in Cobitis. Asexual animals described in other case studies reproduce ameiotically, while Cobitis hybrids described here produce eggs likely through modified meiosis. Therefore, our findings indicate that the effect of asexuality on the rate of chromosomal change may be context-dependent rather than universal and related to particular type of asexual reproduction.

  6. Asexual Reproduction Does Not Apparently Increase the Rate of Chromosomal Evolution: Karyotype Stability in Diploid and Triploid Clonal Hybrid Fish (Cobitis, Cypriniformes, Teleostei.

    Directory of Open Access Journals (Sweden)

    Zuzana Majtánová

    Full Text Available Interspecific hybridization, polyploidization and transitions from sexuality to asexuality considerably affect organismal genomes. Especially the last mentioned process has been assumed to play a significant role in the initiation of chromosomal rearrangements, causing increased rates of karyotype evolution. We used cytogenetic analysis and molecular dating of cladogenetic events to compare the rate of changes of chromosome morphology and karyotype in asexually and sexually reproducing counterparts in European spined loach fish (Cobitis. We studied metaphases of three sexually reproducing species and their diploid and polyploid hybrid clones of different age of origin. The material includes artificial F1 hybrid strains, representatives of lineage originated in Holocene epoch, and also individuals of an oldest known age to date (roughly 0.37 MYA. Thereafter we applied GISH technique as a marker to differentiate parental chromosomal sets in hybrids. Although the sexual species accumulated remarkable chromosomal rearrangements after their speciation, we observed no differences in chromosome numbers and/or morphology among karyotypes of asexual hybrids. These hybrids possess chromosome sets originating from respective parental species with no cytogenetically detectable recombinations, suggesting their integrity even in a long term. The switch to asexual reproduction thus did not provoke any significant acceleration of the rate of chromosomal evolution in Cobitis. Asexual animals described in other case studies reproduce ameiotically, while Cobitis hybrids described here produce eggs likely through modified meiosis. Therefore, our findings indicate that the effect of asexuality on the rate of chromosomal change may be context-dependent rather than universal and related to particular type of asexual reproduction.

  7. The impact of development and population policies on fertility in India.

    Science.gov (United States)

    Jain, A K

    1985-01-01

    This article examines the impact of development and population policies on fertility decline and regional variations in India during the 1970s. Indicators of development at the household level include female literacy and education, infant mortality, and poverty; at the village level they include availability of such social services as schools, medical facilities, and transportation and communication facilities. Multiple regression analysis of data aggregated at the state level demonstrates that conditions conducive to fertility decline include high adult female literacy and low infant mortality as indicators of social development, and high contraceptive use and, to a lesser extent, high female age at marriage as proximate determinants of fertility. There are reasons to believe that India's national family planning program contributed to the decline in fertility observed since the 1960s. The pace of fertility decline in the future will depend upon the pace of infant mortality decline, enhancement in female education, and improvements in family planning programs.

  8. Case series of fertility treatment in HIV-discordant couples (male positive, female negative: the Ontario experience.

    Directory of Open Access Journals (Sweden)

    Trent Newmeyer

    Full Text Available The success of combination antiretroviral therapies for the treatment of human immunodeficiency virus (HIV has resulted in prolonged life expectancy (over 40 years from diagnosis and an improved quality of life for people living with HIV. The risk of vertical HIV transmission during pregnancy has been reduced to less than 1%. As a result of these breakthroughs and as many of these individuals are of reproductive age, fertility issues are becoming increasingly important for this population. One population in which conception planning and reduction of horizontal HIV transmission warrants further research is HIV-discordant couples where the male partner is HIV-positive and the female partner is HIV-negative. Sperm washing is a technique carried out in a fertility clinic that separates HIV from the seminal fluid. Although sperm washing followed by intrauterine insemination significantly reduces the risk of horizontal HIV transmission, there has been limited access to the procedure in North America. Furthermore, little is known about the conception decision-making experiences of HIV-discordant couples who might benefit from sperm washing. Chart reviews and semi-structured interviews were completed with 12 HIV-discordant couples in Ontario, Canada. Couples were recruited through HIV clinics and one fertility clinic that offered sperm washing. Participants identified a number of factors that affected their decision-making around pregnancy planning. Access to sperm washing and other fertility services was an issue (cost, travel and few clinics. Participants identified a lack of information on the procedure (availability, safety. Sources of support (social networks, healthcare providers were unevenly distributed, especially among those who did not disclose their HIV status to friends and family. Finally, the stigmatisation of HIV continues to have a negative affect on HIV-discordant couples and their intentions to conceive. Access to sperm washing and

  9. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Fertil Steril. 2013; 100:1224-31. Chow EJ, et al. Pregnancy after chemotherapy in male and female ... Cancer . Urology. 2016;91:190-6. Loren AW, et al. Fertility preservation for patients with cancer: American ...

  10. Lycosides, Unusual Carotenoid-Derived Terpenoid Glycosides from a Vegetable Juice, Inhibit Asexual Reproduction of the Plant Pathogen Phytophthora.

    Science.gov (United States)

    Iwai, Rika; Han, Chunguang; Govindam, Sudhakar V S; Ojika, Makoto

    2018-01-10

    Vegetable juices, typical culture media for the plant pathogen Phytophthora, effectively induce its asexual reproduction (zoosporangia formation). However, some chromatographic fractions from a vegetable juice were found to inhibit asexual reproduction. Bioassay-guided chromatographic steps led to the isolation of four novel compounds, named lycosides A-D, 1-4, that could be metabolic products from a carotenoid. They showed 50% inhibitory activity against the asexual reproduction of P. capsici at 2.1-7.6 μM. The structure-activity relationship and the universality of the inhibitory activity within the Phytophthora genus were also investigated. In addition, the quantitative analysis of lycosides in fresh vegetables and vegetable juices revealed that tomato is the source of these active substances. These food-derived chemicals could help provide safe agents to control the outbreak of the agricultural pest Phytophthora in fields.

  11. Young female cancer patients' experiences with fertility counselling and fertility preservation-a qualitative small-scale study within the Danish health care setting.

    Science.gov (United States)

    Hoeg, Didde; Schmidt, Lone; Macklon, Kirsten T

    2016-07-14

    Fertility counselling for young women newly diagnosed with cancer is an important field of preconceptional counselling. This qualitative, small-scale study explored how young women newly diagnosed with cancer experienced specialized fertility preservation counselling and treatment in the public Danish health care system. Semi-structured, in-depth interviews were conducted with five women below 40 years recently diagnosed with cancer. All women received fertility counselling by a fertility specialist at the Fertility Clinic, University Hospital of Copenhagen, Denmark before initiation of cancer treatment. Participants were interviewed at a place chosen by them, and interviews were recorded and transcribed verbatim. Data were analysed using systematic text condensation developed by Malterud and inspired by Giorgi's phenomenological analysis. None of the participants were aware that chemotherapy could destroy their eggs. The participants described how specialized fertility counselling and fertility preservation contributed to a belief in life after cancer, which gave them hope that they would survive their cancer disease. Further, the women described how the possibility of fertility preservation removed a huge concern and enabled them to concentrate on their cancer treatment and on getting better. Overall, the specialized fertility counselling and treatment to preserve fertility was highly valued. The women felt it gave them a choice about their future fertility. The fertility expert presented the various fertility-preserving scenarios, and the women were content that they had an actual choice.

  12. LH prevents cisplatin-induced apoptosis in oocytes and preserves female fertility in mouse

    Science.gov (United States)

    Rossi, Valerio; Lispi, Monica; Longobardi, Salvatore; Mattei, Maurizio; Rella, Francesca Di; Salustri, Antonietta; De Felici, Massimo; Klinger, Francesca G

    2017-01-01

    Premature ovarian failure and female infertility are frequent side effects of anticancer therapies, owing to the extreme sensitivity of the ovarian reserve oocytes to the damaging effects of irradiation and chemotherapy on DNA. We report here a robust protective effect of luteinizing hormone (LH) on the primordial follicle pool of prepubertal ovaries against the cisplatin (Cs)-induced apoptosis. In vitro LH treatment of prepubertal ovarian fragments generated anti-apoptotic signals by a subset of ovarian somatic cells expressing LH receptor (LHR) through cAMP/PKA and Akt pathways. Such signals, reducing the oocyte level of pro-apoptotic TAp63 protein and favoring the repair of the Cs-damaged DNA in the oocytes, prevented their apoptosis. Noteworthy, in vivo administration to prepubertal female mice of a single dose of LH together with Cs inhibited the depletion of the primordial follicle reserve caused by the drug and preserved their fertility in reproductive age, preventing significant alteration in the number of pregnancy and of delivered pups. In conclusion, these findings establish a novel ovoprotective role for LH and further support the very attracting prospective to use physiological 'fertoprotective' approaches for preventing premature infertility and risks linked to precocious menopause in young patients who survived cancer after chemotherapy. PMID:27689876

  13. LH prevents cisplatin-induced apoptosis in oocytes and preserves female fertility in mouse.

    Science.gov (United States)

    Rossi, Valerio; Lispi, Monica; Longobardi, Salvatore; Mattei, Maurizio; Rella, Francesca Di; Salustri, Antonietta; De Felici, Massimo; Klinger, Francesca G

    2017-01-01

    Premature ovarian failure and female infertility are frequent side effects of anticancer therapies, owing to the extreme sensitivity of the ovarian reserve oocytes to the damaging effects of irradiation and chemotherapy on DNA. We report here a robust protective effect of luteinizing hormone (LH) on the primordial follicle pool of prepubertal ovaries against the cisplatin (Cs)-induced apoptosis. In vitro LH treatment of prepubertal ovarian fragments generated anti-apoptotic signals by a subset of ovarian somatic cells expressing LH receptor (LHR) through cAMP/PKA and Akt pathways. Such signals, reducing the oocyte level of pro-apoptotic TAp63 protein and favoring the repair of the Cs-damaged DNA in the oocytes, prevented their apoptosis. Noteworthy, in vivo administration to prepubertal female mice of a single dose of LH together with Cs inhibited the depletion of the primordial follicle reserve caused by the drug and preserved their fertility in reproductive age, preventing significant alteration in the number of pregnancy and of delivered pups. In conclusion, these findings establish a novel ovoprotective role for LH and further support the very attracting prospective to use physiological 'fertoprotective' approaches for preventing premature infertility and risks linked to precocious menopause in young patients who survived cancer after chemotherapy.

  14. Young female cancer patients’ experiences with fertility counselling and fertility preservation—a qualitative small-scale study within the Danish health care setting

    Science.gov (United States)

    Hoeg, Didde; Schmidt, Lone; Macklon, Kirsten T.

    2016-01-01

    Introduction Fertility counselling for young women newly diagnosed with cancer is an important field of preconceptional counselling. This qualitative, small-scale study explored how young women newly diagnosed with cancer experienced specialized fertility preservation counselling and treatment in the public Danish health care system. Methods Semi-structured, in-depth interviews were conducted with five women below 40 years recently diagnosed with cancer. All women received fertility counselling by a fertility specialist at the Fertility Clinic, University Hospital of Copenhagen, Denmark before initiation of cancer treatment. Participants were interviewed at a place chosen by them, and interviews were recorded and transcribed verbatim. Data were analysed using systematic text condensation developed by Malterud and inspired by Giorgi’s phenomenological analysis. Results None of the participants were aware that chemotherapy could destroy their eggs. The participants described how specialized fertility counselling and fertility preservation contributed to a belief in life after cancer, which gave them hope that they would survive their cancer disease. Further, the women described how the possibility of fertility preservation removed a huge concern and enabled them to concentrate on their cancer treatment and on getting better. Conclusion Overall, the specialized fertility counselling and treatment to preserve fertility was highly valued. The women felt it gave them a choice about their future fertility. The fertility expert presented the various fertility-preserving scenarios, and the women were content that they had an actual choice. PMID:27413812

  15. Lineage dynamics and mutation-selection balance in non-adapting asexual populations

    Science.gov (United States)

    Pénisson, Sophie; Sniegowski, Paul D.; Colato, Alexandre; Gerrish, Philip J.

    2013-02-01

    In classical population genetics, mutation-selection balance refers to the equilibrium frequency of a deleterious allele established and maintained under two opposing forces: recurrent mutation, which tends to increase the frequency of the allele; and selection, which tends to decrease its frequency. In a haploid population, if μ denotes the per capita rate of production of the deleterious allele by mutation and s denotes the selective disadvantage of carrying the allele, then the classical mutation-selection balance frequency of the allele is approximated by μ/s. This calculation assumes that lineages carrying the mutant allele in question—the ‘focal allele’—do not accumulate deleterious mutations linked to the focal allele. In principle, indirect selection against the focal allele caused by such additional mutations can decrease the frequency of the focal allele below the classical mutation-selection balance. This effect of indirect selection will be strongest in an asexual population, in which the entire genome is in linkage. Here, we use an approach based on a multitype branching process to investigate this effect, analyzing lineage dynamics under mutation, direct selection, and indirect selection in a non-adapting asexual population. We find that the equilibrium balance between recurrent mutation to the focal allele and the forces of direct and indirect selection against the focal allele is closely approximated by γμ/(s + U) (s = 0 if the focal allele is neutral), where γ ≈ eθθ-(ω+θ)(ω + θ)(Γ(ω + θ) - Γ(ω + θ,θ)), \\theta =U/\\tilde {s}, and \\omega =s/\\tilde {s}; U denotes the genomic deleterious mutation rate and \\tilde {s} denotes the geometric mean selective disadvantage of deleterious mutations elsewhere on the genome. This mutation-selection balance for asexual populations can remain surprisingly invariant over wide ranges of the mutation rate.

  16. Molecular mechanisms of fertilization: the role of male factor

    Directory of Open Access Journals (Sweden)

    Ewa Maria Kratz

    2011-11-01

    Full Text Available Fertilization, the fusion of male and female gametes, is an incompletely known, multistep, complex process, in which many factors participate. Fertilization is a precisely regulated, species-specific process, but some cellular mechanisms are similar for many mammal species. The studies of mechanisms of male and female gamete production enable understanding of fertilization issues and, as a result, make the analysis of the causes of infertility possible. Male and female infertility is a progressive phenomenon. The development of laboratory medicine enables the analysis of molecular aspects of the reactions between gametes, which may result in better diagnosis of many infertility cases and indicate the direction of therapeutic management. The fertilization process is accompanied by many biochemical reactions, in which glycoproteins present in human ejaculate play a very important role. Glycan structures enable glycoproteins to participate in the interactions between cells, including those between gametes. The analysis of the glycosylation profile and degree of ejaculate glycoproteins not only contributes to deepening the knowledge about mechanisms accompanying the fertilization process, but also may be useful as an additional diagnostic marker of male infertility.The aim of the present review is to approach selected molecular mechanisms occurring in the male genital tract, related to the fertilization process, as well as to analyze their influence on male fertility.

  17. Fertility counseling and preservation practices in youth with lupus and vasculitis undergoing gonadotoxic therapy.

    Science.gov (United States)

    Nahata, Leena; Sivaraman, Vidya; Quinn, Gwendolyn P

    2016-11-01

    To assess fertility counseling and preservation practices among children, adolescents, and young adults with rheumatic diseases undergoing cyclophosphamide (CTX) treatment. Retrospective chart review (2006-2016). Academic pediatric center. Male and female patients with systemic lupus erythematosus, Wegener's granulomatosis/granulomatosis with polyangiitis, or other vaculitides, receiving CTX treatment. None. Documentation of fertility counseling and fertility preservation. A total of 58 subjects met the inclusion criteria; 5 were excluded due to incomplete records, thus N = 53. Of these 75% were female (N = 40). Median age was 14 years at diagnosis and 15 years at first CTX treatment. A total of 51% of subjects (69% of males and 45% of females) had no documentation about potential fertility loss before CTX treatment. Among females where fertility counseling was documented, the only fertility preservation option discussed was leuprolide acetate (LA), which was pursued in all of these cases. Of 13 males (77% postpubertal), 3 were offered sperm banking, of whom 2 declined and the other attempted after treatment began and was azoospermic. Of 53 patients, 1 was referred to a fertility specialist. Mean cumulative CTX dose was 9.2 g in males and 8 g in females. Based on these findings, increasing awareness about infertility risk, fertility preservation options, and referral to fertility specialists is needed among pediatric rheumatologists. Prospective studies are needed to assess fertility outcomes in this patient population (including effectiveness of LA with regard to pregnancy rates [PRs]), as well as barriers/facilitators to fertility counseling and fertility preservation. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  18. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Ethics Committee of the American Society for Reproductive Medicine. Fertility preservation and reproduction in patients facing gonadotoxic therapies: a committee opinion. Fertil Steril. 2013; 100:1224-31. Chow EJ, et al. Pregnancy after chemotherapy in male and female survivors of ...

  19. Low fertilization rates in a pelagic copepod caused by sexual selection?

    DEFF Research Database (Denmark)

    Ceballos, Sara; Sichlau, Mie Hylstofte; Heuschele, Jan

    2014-01-01

    We studied female fertilization status in North Sea summer populations and laboratory cultures of the marine copepod Temora longicornis and found fractions of fertilized females in both field and laboratory populations that were much smaller (<50%) than predicted by a theoretical model that assum...

  20. Fertility in female reindeer: the effects of nutrition and growth

    Directory of Open Access Journals (Sweden)

    N. J.C. Tyler

    1987-06-01

    Full Text Available Pregnancy rates in juvenile reindeer (Rangifer tarandus vary considerably both within and between flocks. This potentially has considerable economic significance for reindeer husbandry. This paper discusses the influence of nutrition and growth on fertility in female reindeer using examples taken from the literature. Fertility in reindeer is related to body weight, like in many other mammals, but the relationship is not invariant. Weight-specific pregnancy rates appear to be density dependent in juvenile reindeer although not in adults. This strongly suggests that nutrition has an important influence on fertility in juveniles.Fruktbarhet hos simler: effekter av ernæring og vekst.Abstract in Norwegian / Sammendrag: Drektighetsprosenten i ungrein varierer sterkt fra individ til individ og fra flokk til flokk. En høy fruktbarhet i reinflokken er selve grunnlaget for en vellykket reindrift. Overraskende er det derfor at man vet lite om hvilke faktorer som bestemmer om rein skal bli drektig eller ikke. I denne artikkelen blir effekten av ernæring på reinsimlenes fruktbarhet diskutert. Undersøkelser indikerer at rein er som andre pattedyr, der fruktbarheten er relatert til kroppsvekten. Forholdet mellom reinens kroppsvekt og fruktbarhet varierer likevel sterkt. Mye tyder på at drektighetsprosenten i ungrein er avhengig av reintettheten. Dette indikerer at ernæringen er en viktig faktor når det gjelder fruktbarhet i ungrein. Vekt-spesifikk fruktbarhet kan derfor være en brukbar indikator for reinflokkens fortilgang. I prinsippet vil slike fruktbarhetsundersøkelser gi et en brukbar indikator for reinflokkens fortilgang. I prinsippet vil slike fruktbarhetsundersøkelser gi et tidlig varsel om reintallet er for høyt i forhold til beitegrunnlaget før en markert nedgang i slaktevekten observeres.Ravitsemustilan ja kasvun vaikutus vaatimien hedelmållisyyteen.Abstract in Finnish / Yhteenveto: Nuorten porojen hedelmåliisyys vaihtelee suuresti

  1. Fertility preservation in young cancer patients

    Directory of Open Access Journals (Sweden)

    Ariel Revel

    2010-01-01

    Full Text Available As a result of advances in treatment, almost 80% of children and adolescents who receive a diagnosis of cancer become long-term survivors. The increased survival rate of children and adolescents with cancer has resulted in a major interest in the long-term effects of cancer treatment on the possibility for future fertility. Currently established methods for the preservation of fertility are available only for pubertal males and females. Pubertal male cancer patients should be encouraged to freeze numerous sperm samples even when sperm count and motility are poor. In these cases, intracytoplasmic sperm injection is a powerful technique compared with intrauterine insemination since thawed sperm samples with poor parameters can produce relatively high fertilization rates resulting in normal pregnancies and deliveries. Married pubertal women should be proposed ovulation induction, follicular aspiration, and fertilization with husband sperm. Single women could benefit from vitrification of oocytes. This requires a delay of about 3 weeks in the commencement of chemotherapy to enable follicular growth. Fertility preservation for prepubertal patients is more of a problem. Young girls could be offered cryopreservation of gametes in the gonadal tissue. Cryopreservation of testicular tissue was suggested for fertility preservation for young boys, but this method is totally experimental and not currently offered. Discussing future fertility is part of the consultation of young female and male patients facing potentially gonadotoxic cancer therapy. It is the role of reproductive specialists to create various options in their laboratory to preserve fertility potential of cancer patients.

  2. Slow fertilization of stickleback eggs: the result of sexual conflict?

    Directory of Open Access Journals (Sweden)

    Frommen Joachim G

    2006-05-01

    Full Text Available Abstract Background The fertilization success in sperm competition in externally fertilizing fish depends on number and quality of sperm. The time delay between sequential ejaculations may further influence the outcome of sperm competition. Such a time interval can load the raffle over fertilization if fertilization takes place very fast. Short fertilization times are generally assumed for externally fertilizing fish such as the three-spined stickleback (Gasterosteus aculeatus. In this pair-spawning fish, territorial males often try to steal fertilizations in nests of neighbouring males. This sneaking behaviour causes sperm competition. Sneakers will only get a share of paternity when eggs are not fertilized immediately after sperm release. Contrary to males, females may be interested in multiple paternity of their clutch of eggs. There thus may be a sexual conflict over the speed of fertilization. Results In this study we used two different in vitro fertilization experiments to assess how fast eggs are fertilized in sticklebacks. We show that complete fertilization takes more than 5 min which is atypically long for externally fertilizing fishes. Conclusion This result suggests that the time difference does not imply high costs to the second stickleback male to ejaculate. Slow fertilization (and concomitant prolonged longevity of sperm may be the result of sexual conflict in which females aimed at complete fertilization and/or multiple paternity.

  3. Evidence of parasexual activity in "asexual amoebae" Cochliopodium spp. (Amoebozoa): extensive cellular and nuclear fusion.

    Science.gov (United States)

    Tekle, Yonas I; Anderson, O Roger; Lecky, Ariel F

    2014-09-01

    The majority of microbial eukaryotes have long been considered asexual, though new evidence indicates sex, or sexual-like (parasexual) behaviors that deviate from the usual union of two gametes, among other variant aspects. Over a dozen amoebozoans are implicated to have sexual stages. However, the exact mechanism by which sex occurs in these lineages remains elusive. This is mainly due to the diverse quality and cryptic nature of their life cycle. In this study we present evidence of some previously unreported aspects of the life cycle of an amoeba, Cochliopodium, that undergoes unusual intraspecific interactions using light microscopy and immunocytochemistry. Similar to other amoebozoans, Cochliopodium, is considered asexual with no published reports of sex or parasexuality. We also investigated environmental conditions that govern the observed intraspecific interactions. Both light microscopic and immunocytochemistry evidence demonstrates Cochliopodium undergoes cellular fusion (plasmogamy) and nuclear fusion (karyogamy). Large plasmodia eventually undergo karyogamy and contain large fused, polyploid, nuclei. These are observed to fragment, subsequently, by karyotomy (nuclear fission) and cytoplasmic fission to yield uninucleated amoebae. This process could lead to a non-meiotic, parasexual exchange of chromosomes in Cochliopodium. These findings strongly suggest that Cochliopodium is involved in parasexual activity and should no longer be considered strictly asexual. Copyright © 2014 Elsevier GmbH. All rights reserved.

  4. Fertility preservation in Turner syndrome.

    Science.gov (United States)

    Grynberg, Michaël; Bidet, Maud; Benard, Julie; Poulain, Marine; Sonigo, Charlotte; Cédrin-Durnerin, Isabelle; Polak, Michel

    2016-01-01

    Premature ovarian insufficiency is a relatively rare condition that can appear early in life. In a non-negligible number of cases the ovarian dysfunction results from genetic diseases. Turner syndrome (TS), the most common sex chromosome abnormality in females, is associated with an inevitable premature exhaustion of the follicular stockpile. The possible or probable infertility is a major concern for TS patients and their parents, and physicians are often asked about possible options to preserve fertility. Unfortunately, there are no recommendations on fertility preservation in this group. The severely reduced follicle pool even during prepubertal life represents the major limit for fertility preservation and is the root of numerous questions regarding the competence of gametes or ovarian tissue crybanked. In addition, patients suffering from TS show higher than usual rates of spontaneous abortion, fetal anomaly, and maternal morbidity and mortality, which should be considered at the time of fertility preservation and before reutilization of the cryopreserved gametes. Apart from fulfillment of the desire of becoming genetic parents, TS patients may be potential candidates for egg donation, gestational surrogacy, and adoption. The present review discusses the different options for preserving female fertility in TS and the ethical questions raised by these approaches. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  5. [Stress and fertility].

    Science.gov (United States)

    Ősapay, György; Ősapay, Klára

    2015-08-30

    In Western countries, sperm quality and fertility of men significantly worsened. Female infertility does not show a better trend either. Subtle defects in the reproductive functions can not be explained by the current methods, and "unexplained infertility" is becoming a more common diagnosis. Every year 1 million couples seek expensive and time consuming fertility treatment in the world. Deeper understanding of an unhealthy lifestyle and the environmental damages may lead to personalized treatments to increase the chance of conception.The effects of various stressors on the male and female reproductive performance were scientifically substantiated by Selye and coworkers in 1976. Cognitive therapy methods can be applied against emotional stressors, supplementation by antioxidants against reactive oxygen compounds, and administration of vitamins and trace elements, especially when deficiency is found, may help before medical intervention on a rational and economical way in the fight against infertility.

  6. Incidence and prevalence of sexual dysfunction in infertile females

    Directory of Open Access Journals (Sweden)

    Rohina S. Aggarwal

    2013-09-01

    Results: In our study 170 (63.67% patients in the infertile group (n = 267 had female sexual dysfunction as compared to108 (46.35% in the fertile group (n = 233, which is statistically significant (P 0.0001. Most common dysfunction observed was arousal (70% in infertile patients. Common dysfunctions observed in fertile females were desire (40% and orgasm (40%. FSD was significantly higher in infertile females of the 31–37 years age group (P 0.002, while more common in fertile females of >42 years of age (P < 0.0001. Higher female sexual dysfunction was observed in illiterate infertile females (P 0.039. Among the pathological factors endometriosis was the statistically significant factor associated with female sexual dysfunction and infertility (P < 0.0001. No significant correlation in duration of infertility or type of infertility was observed with female sexual dysfunction. Female sexual dysfunction as the cause or the effect should be ascertained in infertility.

  7. Possible Outcome of Fenugreek Seeds Powder Administration on the Fertility of Female and Male Albino Rat

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, M F; El-Tawill, G.A., E-mail: gkyrillos@hotmail.co [Radiation Biology Department, National Centre for Radiation Research and Technology (NCRRT), Atomic Energy Authority, Cairo (Egypt)

    2010-07-01

    Fenugreek (Trigonella foenum-graecum) is an annual plant from the family of Papilionaceae-Leguminosae that has been credited with many medicinal properties. The current study aims to evaluate the possible fertility activity of fenugreek seeds powder on female and male albino rats. To achieve the theme, fenugreek seeds powder (200 mg/rat) were daily administered orally to both female and male Wistar rats for 15 and 30 consecutive days, after which the rats were sacrificed for both biochemical and histopathological observations. Fenugreek treatment significantly decreased the serum cholesterol levels in both female and male rats with a marked increase in the ovary and testis cholesterol levels following 30 days of consecutive administration. The circulating serum female hormones showed an initial elevation at the end of 15 days of fenugreek intake followed by a significant drop in the group of rats that continued to receive the daily fenugreek dose for 30 days. These observations were supported by the notable decline in the ovarian weights further validated by their ovarian histological sections revealing remarkable dissolution of some follicles and prominent abundance of inflammatory cells. In the 30 days interval treated males, the serum testosterone hormone concentrations significantly declined and the testis weights were reduced with evident damage to the seminiferous tubules and interstitial tissues as shown by the histopathological picture of testis tissue sections. Accordingly, it can be deduced that fenugreek seeds powder exert a significant antifertility adverse effect on the female and male rats when supplemented at a considerable dose for an extended time interval

  8. Changes in genomic methylation patterns during the formation of triploid asexual dandelion lineages

    NARCIS (Netherlands)

    Verhoeven, K.J.F.; Van Dijk, P.J.; Biere, A.

    2010-01-01

    DNA methylation is an epigenetic mechanism that has the potential to affect plant phenotypes and that is responsive to environmental and genomic stresses such as hybridization and polyploidization. We explored de novo methylation variation that arises during the formation of triploid asexual

  9. Time trends in biological fertility in Western Europe

    DEFF Research Database (Denmark)

    Joffe, Michael; Holmes, Jane; Jensen, Tina Kold

    2013-01-01

    analyses demonstrated that this rise was visible as a male cohort effect for both TTP and contraceptive failure. On the other hand, the female birth cohort effect showed a slight fall in the first half of the study period for both TTP and contraceptive failure. As a period effect, fertility remained...... of which are calculated to be small. The declining female fertility accords with a falling dizygotic twinning rate during the same period.......We investigated trends in biological fertility in a comprehensive analysis of 5 major European data sets with data on time to pregnancy (TTP) and proportion of contraceptive failures. In particular, we distinguished a period effect from a birth cohort effect (lifelong tendency) in both sexes...

  10. Poverty, Fertility and Child Labor: Does Demand Theory of Fertility Matter? An Exploratory Study in India

    Directory of Open Access Journals (Sweden)

    Gargi Bhattacharya

    2013-07-01

    Full Text Available It is hypothesized that fertility, poverty and child labor are jointly determined variables; neither can be assumed to be an independent determinant of the other. In a simultaneous equation framework, we find that demand theory of fertility does hold good even at the lower level of income where the females are compelled to go outside home for cash in order to avoid destitute and they prefer less number of children. Therefore, in order to regulate fertility in India, one can suggest increasing female employment opportunity at the informal sector, since formal sector job is severely restricted in India. It is observed that child labor is caused by lower health status and poor human capital investment. Thus, if we increase the per capita social sector expenditure on education and healthcare, it directly augments enrollment of the children in school. Since health and education is treated as complementary to each other, a rise in social sector investment has some spillover benefits to the society.

  11. Sexual dimorphism in white campion: deletion on the Y chromosome results in a floral asexual phenotype

    International Nuclear Information System (INIS)

    Farbos, I.; Veuskens, J.; Vyskot, B.; Oliveira, M.; Hinnisdaels, S.; Aghmir, A.; Mouras, A.; Negrutiu, I.

    1999-01-01

    White campion is a dioecious plant with heteromorphic X and Y sex chromosomes. In male plants, a filamentous structure replaces the pistil, while in female plants the stamens degenerate early in flower development. Asexual (asx) mutants, cumulating the two developmental defects that characterize the sexual dimorphism in this species, were produced by gamma ray irradiation of pollen and screening in the M1 generation. The mutants harbor a novel type of mutation affecting an early function in sporogenous/parietal cell differentiation within the anther. The function is called stamen-promoting function (SPF). The mutants are shown to result from interstitial deletions on the Y chromosome. We present evidence that such deletions tentatively cover the central domain on the (p)-arm of the Y chromosome (Y2 region). By comparing stamen development in wild-type female and asx mutant flowers we show that they share the same block in anther development, which results in the production of vestigial anthers. The data suggest that the SPF, a key function(s) controlling the sporogenous/parietal specialization in premeiotic anthers, is genuinely missing in females (XX constitution). We argue that this is the earliest function in the male program that is Y-linked and is likely responsible for ''male dimorphism'' (sexual dimorphism in the third floral whorl) in white campion. More generally, the reported results improve our knowledge of the structural and functional organization of the Y chromosome and favor the view that sex determination in this species results primarily from a trigger signal on the Y chromosome (Y1 region) that suppresses female development. The default state is therefore the ancestral hermaphroditic state

  12. Characterization of leaf area of Agave fourcroydes Lem. plants obtained from asexual propagation

    Directory of Open Access Journals (Sweden)

    Maryla Sosa del Castillo

    2014-01-01

    Full Text Available The henequen (Agave fourcroydes Lem. is a crop of great economic importance. This study was aimed to characterize the leaf surface of henequen plants variety `Sac Ki' obtained by asexual propagation methods. In vitro plants, shoots of bulbils of in vitro plants, shoots of rhizomes of in vitro plants, shoots of bulbils of field plants and shoots of field rhizomes were used. At 7 and 15 months after planting in the nursery, the epidermis was characterized through the stomatal index and stomatal density. Moreover, the conductor vessels and fiber bundles in leaf mesophyll, were characterized. It was found that the leaf surface of henequen plants variety `Sac Ki' obtained by different methods of asexual propagation showed similar anatomical structures. However, it was observed that in vitro plants were different from the rest in terms of stomatal index and stomatal density in both time points. It was suggesting a accommodate response to environmental conditions. Key words: stomatic density, stomatic index, in vitro plants

  13. Parthenogenesis in Komodo dragons.

    Science.gov (United States)

    Watts, Phillip C; Buley, Kevin R; Sanderson, Stephanie; Boardman, Wayne; Ciofi, Claudio; Gibson, Richard

    2006-12-21

    Parthenogenesis, the production of offspring without fertilization by a male, is rare in vertebrate species, which usually reproduce after fusion of male and female gametes. Here we use genetic fingerprinting to identify parthenogenetic offspring produced by two female Komodo dragons (Varanus komodoensis) that had been kept at separate institutions and isolated from males; one of these females subsequently produced additional offspring sexually. This reproductive plasticity indicates that female Komodo dragons may switch between asexual and sexual reproduction, depending on the availability of a mate--a finding that has implications for the breeding of this threatened species in captivity. Most zoos keep only females, with males being moved between zoos for mating, but perhaps they should be kept together to avoid triggering parthenogenesis and thereby decreasing genetic diversity.

  14. How the FMR1 gene became relevant to female fertility and reproductive medicine

    Directory of Open Access Journals (Sweden)

    Norbert eGleicher

    2014-08-01

    Full Text Available This manuscript describes the 6-year evolution of our center’s research into ovarian functions of the FMR1 gene, which led to the identification of a new normal CGGn range of 26-34. This new normal range, in turn, led to definitions of different alleles (haplotypes based on whether no, one or both alleles are within range. Specific alleles then were demonstrated to represent distinct ovarian aging patterns, suggesting an important FMR1 function in follicle recruitment and ovarian depletion of follicles. So called low alleles, characterized by CGGn34 alleles. Because low FMR1 alleles present in approximately 25% of all females, FMR1 testing at young ages may offer an opportunity for earlier diagnosis of OPOI than current practice allows. Earlier diagnosis of OPOI, in turn, would give young women the options of reassessing their reproductive schedules and/or pursue fertility preservation via oocyte cryopreservation when most effective.

  15. Hispanic Adolescent Fertility.

    Science.gov (United States)

    Darabi, Katherine F.; And Others

    1986-01-01

    Discusses fertility of Hispanic adolescents in the United States. Summarizes what is known about sexuality, contraception, pregnancy, and childbearing among male and female Hispanics of various countries of origin. Indicates Hispanic adolescent birthrates fall between those of non-Hispanic Whites and Blacks, but there is considerable within-group…

  16. Natural epigenetic variation contributes to heritable flowering divergence in a widespread asexual dandelion lineage

    NARCIS (Netherlands)

    Wilschut, R.A.; Oplaat, C.; Snoek, B.; Kirschner, J.; Verhoeven, K.J.F.

    2016-01-01

    Epigenetic variation has been proposed to contribute to the success of asexual plants, either as a contributor to phenotypic plasticity or by enabling transient adaptation via selection on transgenerationally stable, but reversible, epialleles. While recent studies in experimental plant populations

  17. The evolution of polyandry: patterns of genotypic variation in female mating frequency, male fertilization success and a test of the sexy-sperm hypothesis.

    Science.gov (United States)

    Simmons, L W

    2003-07-01

    The sexy-sperm hypothesis predicts that females obtain indirect benefits for their offspring via polyandy, in the form of increased fertilization success for their sons. I use a quantitative genetic approach to test the sexy-sperm hypothesis using the field cricket Teleogryllus oceanicus. Previous studies of this species have shown considerable phenotypic variation in fertilization success when two or more males compete. There were high broad-sense heritabilities for both paternity and polyandry. Patterns of genotypic variance were consistent with X-linked inheritance and/or maternal effects on these traits. The genetic architecture therefore precludes the evolution of polyandry via a sexy-sperm process. Thus the positive genetic correlation between paternity in sons and polyandry in daughters predicted by the sexy-sperm hypothesis was absent. There was significant heritable variation in the investment by females in ovaries and by males in the accessory gland. Surprisingly there was a very strong genetic correlation between these two traits. The significance of this genetic correlation for the coevolution of male seminal products and polyandry is discussed.

  18. In-Vitro Fertilization Practice: Awareness and Perceptions ...

    African Journals Online (AJOL)

    BACKGROUND: In-vitro fertilization(IVF) is a procedure that is one of the options in managing infertility. It involves fertilizing the egg from the female with the spermatozoa from the male outside the human body. It is a common practice in the developed world. However it is still a new phenomenon in the developing countries.

  19. Gendered Divisions of Fertility Work: Socioeconomic Predictors of Female versus Male Sterilization

    Science.gov (United States)

    Bertotti, Andrea M.

    2013-01-01

    Domestic labor researchers have examined a multitude of duties disproportionately performed by women, yet the responsibility associated with navigating a couple's fertility--fertility work--has been overlooked. Using data from the 2006-2010 National Survey of Family Growth ("N" = 1,415), the author examined how racial and socioeconomic…

  20. Obesity and female fertility: a primary care perspective.

    Science.gov (United States)

    Wilkes, Scott; Murdoch, Alison

    2009-07-01

    Infertility affects approximately one in six couples during their lifetime. Obesity affects approximately half of the general population and is thus a common problem among the fertile population. Obese women have a higher prevalence of infertility compared with their lean counterparts. The majority of women with an ovulatory disorder contributing to their infertility have polycystic ovary syndrome (PCOS) and a significant proportion of women with PCOS are obese. Ovulation disorders and obesity-associated infertility represent a group of infertile couples that are relatively simple to treat. Maternal morbidity, mortality and fetal anomalies are increased with obesity and the success of assisted reproductive technology (ART) treatments is significantly reduced for obese women. Body mass index (BMI) treatment limits for ART throughout the UK vary. The mainstay for treatment is weight loss, which improves both natural fertility and conception rates with ART. The most cost-effective treatment strategy for obese infertile women is weight reduction with a hypo-caloric diet. Assisted reproduction is preferable in women with a BMI of 30 kg/m(2) or less and weight loss strategies should be employed within primary care to achieve that goal prior to referral.

  1. Memory and obesity affect the population dynamics of asexual freshwater planarians

    International Nuclear Information System (INIS)

    Dunkel, Jörn; Talbot, Jared; Schötz, Eva-Maria

    2011-01-01

    Asexual reproduction in multicellular organisms is a complex biophysical process that is not yet well understood quantitatively. Here, we report a detailed population study for the asexual freshwater planarian Schmidtea mediterranea, which can reproduce via transverse fission due to a large stem cell contingent. Our long-term observations of isolated non-interacting planarian populations reveal that the characteristic fission waiting time distributions for head and tail fragments differ significantly from each other. The stochastic fission dynamics of tail fragments exhibits non-negligible memory effects, implying that an accurate mathematical description of future data should be based on non-Markovian tree models. By comparing the effective growth of non-interacting planarian populations with those of self-interacting populations, we are able to quantify the influence of interactions between flatworms and physical conditions on the population growth. A surprising result is the non-monotonic relationship between effective population growth rate and nutrient supply: planarians exhibit a tendency to become 'obese' if the feeding frequency exceeds a critical level, resulting in a decreased reproduction activity. This suggests that these flatworms, which possess many genes homologous to those of humans, could become a new model system for studying dietary effects on reproduction and regeneration in multicellular organisms

  2. "Asexual propagation of a virulent clone complex in human and feline outbreak of sporotrichosis"

    NARCIS (Netherlands)

    Teixeira, Marcus de Melo; Rodrigues, Anderson Messias; Tsui, Clement K M; de Almeida, Luiz Gonzaga Paulo; Van Diepeningen, Anne D; Gerrits van den Ende, Bert; Fernandes, Geisa Ferreira; Kano, Rui; Hamelin, Richard C; Lopes-Bezerra, Leila Maria; Ribeiro Vasconcelos, Ana Tereza; de Hoog, Sybren; de Camargo, Zoilo Pires; Felipe, Maria Sueli Soares

    2014-01-01

    Sporotrichosis is one of the most frequent subcutaneous fungal infections to human and animals caused by members of the plant-associated, dimorphic genus Sporothrix. Three of the four medically important Sporothrix species found in Brazil have been considered asexual, as no sexual stage has ever

  3. Fertility among female hairdressers.

    Science.gov (United States)

    Axmon, Anna; Rylander, Lars; Lillienberg, Linnea; Albin, Maria; Hagmar, Lars

    2006-02-01

    The study investigated whether working as a hairdresser has a negative impact on fertility, measured as time to pregnancy and miscarriage risk. Self-administered questionnaires were sent to 5289 Swedish hairdressers (response rate 50%) and to 5299 age-matched women from the general Swedish population (response rate 54%). Information was collected on time to pregnancy or trying time for women who had tried, but failed, to conceive at the time of the study. The outcome of the pregnancy was determined and categorized as either miscarriage or stillbirth or live birth. The hairdressers were compared with the referents with respect to these two outcomes. Within the hairdresser cohort, the effects of hair treatments, as well as physical workload and stress were investigated. The hairdressers were less successful than the reference cohort in conceiving (fecundability ratio 0.91, 95% confidence interval 0.83-0.99). The effect was reduced after first-month conceptions were excluded, the indication being that the effect may be the result of birth control bias. Within the hairdresser cohort, a self-perceived stressful work situation seemed to prolong the time to pregnancy. No effects were found for the different chemical hair treatments. There was no cohort difference with respect to miscarriage risk (odds ratio 1.12, 95% confidence interval 0.88-1.42), but miscarriage risks were increased for most of the hair treatments and for self-perceived stressful work situations. However, none of these effects were statistically significant. The present study indicates a negative impact on time to pregnancy and miscarriage risk for working as a hairdresser".

  4. Barriers to Managing Fertility: Findings From the Understanding Fertility Management in Contemporary Australia Facebook Discussion Group.

    Science.gov (United States)

    Holton, Sara; Rowe, Heather; Kirkman, Maggie; Jordan, Lynne; McNamee, Kathleen; Bayly, Christine; McBain, John; Sinnott, Vikki; Fisher, Jane

    2016-02-15

    As part of research investigating the complexities of managing fertility in Australia, public opinions about how Australians manage their fertility were sought from women and men. To identify public opinion about sexual and reproductive health in Australia. To ensure access to a diverse group of people throughout Australia, an online group was advertised and convened on Facebook from October through December 2013. In a closed-group moderated discussion, participants responded to questions about how people in Australia attempt to manage three aspects of fertility: avoiding pregnancy, achieving pregnancy, and difficulties conceiving. Nonidentifiable demographic information was sought; no personal accounts of fertility management were requested. The discussion transcript was analyzed thematically. There were 61 female and 2 male Facebook users aged 18 to 50 years living in Australia participating in the study. Four main themes about fertility management were identified: access, geographical location, knowledge, and cost. Participants reported that young people and people from rural areas face barriers accessing contraception and fertility services. Limited knowledge about sex and reproduction and the cost of fertility services and contraception were also said to impede effective fertility management. Reasons for inequalities in effective fertility management that are amenable to change were identified. Facebook is an effective method for gaining insights into public opinion about sexual and reproductive health.

  5. Men perceive their female partners, and themselves, as more attractive around ovulation

    NARCIS (Netherlands)

    Cobey, Kelly D.; Buunk, Abraham P.; Pollet, Thomas V.; Klipping, Christine; Roberts, S. Craig

    2013-01-01

    The purpose of this study was to test whether men perceive changes in their female partner's attractiveness as a function of her fertility status. We further tested how both male and female self-perception varies in relation to female fertility status. This study benefits from the use of

  6. Mating type gene analysis in apparently asexual Cercospora species is suggestive of cryptic sex

    NARCIS (Netherlands)

    Groenewald, M.; Groenewald, J.Z.; Harrington, T.C.; Abeln, E.C.A.; Crous, P.W.

    2006-01-01

    The genus Cercospora consists of numerous important, apparently asexual plant pathogens. We designed degenerate primers from homologous sequences in related species to amplify part of the C. apii, C. apiicola, C. beticola, C. zeae-maydis and C. zeina mating type genes. Chromosome walking was used to

  7. Induction of cell death on Plasmodium falciparum asexual blood stages by Solanum nudum steroids

    DEFF Research Database (Denmark)

    López, Mary Luz; Vommaro, Rossiane; Zalis, Mariano

    2010-01-01

    Solanum nudum Dunal (Solanaceae) is a plant used in traditional medicine in Colombian Pacific Coast, from which five steroids denominated SNs have been isolated. The SNs compounds have antiplasmodial activity against asexual blood stages of Plasmodium falciparum strain 7G8 with an IC50 between 20...

  8. Fertility outcomes in asthma

    DEFF Research Database (Denmark)

    Gade, Elisabeth Juul; Thomsen, Simon Francis; Lindenberg, Svend

    2016-01-01

    Evidence is increasing of an association between asthma and aspects of female reproduction. However, current knowledge is limited and furthermore relies on questionnaire studies or small populations. In a prospective observational cohort study to investigate whether time to pregnancy, the number...... of fertility treatments, and the number of successful pregnancies differ significantly between women with unexplained infertility with and without asthma.245 women with unexplained infertility (aged 23-45 years) underwent questionnaires and asthma and allergy testing while undergoing fertility treatment. 96...... women entering the study had either a former doctor's diagnosis of asthma or were diagnosed with asthma when included. After inclusion they were followed for a minimum of 12 months in fertility treatment, until they had a successful pregnancy, stopped treatment, or the observation ended.The likelihood...

  9. Cold-shock eliminates female nucleus in fertilized eggs to induce androgenesis in the loach (Misgurnus anguillicaudatus, a teleost fish

    Directory of Open Access Journals (Sweden)

    Morishima Kagayaki

    2011-11-01

    Full Text Available Abstract Background Androgenesis (all-male inheritance is generally induced by means of irradiating the eggs to inactivate the maternal genome, followed by fertilization with normal sperm. In fish, the conventional technique for induced androgenesis has been applied for rapid fixation to traits, recovery of cryopreserved genotypes, sex-control, etc. A new method of androgenesis that eliminates the need to irradiate the egg was proposed using the loach, Misgurnus anguillicaudatus (a teleost fish. Results When the eggs of wild-type females were fertilized with sperm of albino or orange phenotype males and cold-shocked at 0 to 3°C for 60 min duration just after fertilization, generally more than 30% (with a peak of 100% of the hatched progeny were androgenotes. While a few of them were the normal diploid, most of them turned out to be abnormal haploid. All-male inheritance was verified by the expression of the recessive color trait (albino or orange and microsatellite genotypes comprising only paternally derived alleles. Nuclear behavior after the cold-shock treatment was traced by microscopic observation of DAPI (4'6-diamidino-2-phenylindole-stained samples and hematoxylin-eosin stained histological sections, and the extrusion of egg (maternal nucleus was observed in eggs treated in the optimum timing. Conclusion In this paper, we demonstrate that cold-shock treatment (at 0 and 3°C of loach eggs for 60 min just after fertilization successfully induces androgenetic haploid development. The most likely mechanism of cold-shock induced androgenesis is an elimination of the egg nucleus together along with the second polar body and subsequent development of a decondensed sperm nucleus or male pronucleus.

  10. A Unique Egg Cortical Granule Localization Motif Is Required for Ovastacin Sequestration to Prevent Premature ZP2 Cleavage and Ensure Female Fertility in Mice.

    Directory of Open Access Journals (Sweden)

    Bo Xiong

    2017-01-01

    Full Text Available Monospermic fertilization is mediated by the extracellular zona pellucida composed of ZP1, ZP2 and ZP3. Sperm bind to the N-terminus of ZP2 which is cleaved after fertilization by ovastacin (encoded by Astl exocytosed from egg cortical granules to prevent sperm binding. AstlNull mice lack the post-fertilization block to sperm binding and the ability to rescue this phenotype with AstlmCherry transgenic mice confirms the role of ovastacin in providing a definitive block to polyspermy. During oogenesis, endogenous ovastacin traffics through the endomembrane system prior to storage in peripherally located cortical granules. Deletion mutants of ovastacinmCherry expressed in growing oocytes define a unique 7 amino acid motif near its N-terminus that is necessary and sufficient for cortical granule localization. Deletion of the 7 amino acids by CRISPR/Cas9 at the endogenous locus (AstlΔ prevents cortical granule localization of ovastacin. The misdirected enzyme is present within the endomembrane system and ZP2 is prematurely cleaved. Sperm bind poorly to the zona pellucida of AstlΔ/Δ mice with partially cleaved ZP2 and female mice are sub-fertile.

  11. Sildenafil citrate (Viagra) impairs fertilization and early embryo development in mice.

    Science.gov (United States)

    Glenn, David R J; McClure, Neil; Cosby, S Louise; Stevenson, Michael; Lewis, Sheena E M

    2009-03-01

    To determine the effects of sildenafil citrate, a cyclic monophosphate-specific type 5 phosphodiesterase inhibitor known to affect sperm function, on fertilization and early embryo cleavage. This acute mammal study included male and female mice assigned randomly, the females sacrificed after mating and their oocytes/embryos evaluated at four time periods after treatment. Academic research environment. Male and female CBAB(6) mice. Female mice were injected intraperitoneally with 5 IU gonadotropin (hCG) to stimulate follicular growth and induce ovulation. They were each caged with a male that had been gavaged with sildenafil citrate (0.06 mg/0.05 mL) and allowed to mate. After 12, 36, 60, and 84 h, females were killed, their oviducts were dissected out, and retrieved embryos were assessed for blastomere number and quality. Fertilization rates and numbers of embryos were evaluated after treatment. Fertilization rates (day 1) were markedly reduced (-33%) in matings where the male had taken sildenafil citrate. Over days 2-4, the numbers of embryos developing in the treated group were significantly fewer than in the control group. There was also a trend for impaired cleavage rates within those embryos, although this did not reach significance. The impairments to fertility caused by sildenafil citrate have important implications for infertility centers and for couples who are using this drug precoitally while attempting to conceive.

  12. Young female cancer patients? experiences with fertility counselling and fertility preservation?a qualitative small-scale study within the Danish health care setting

    OpenAIRE

    Hoeg, Didde; Schmidt, Lone; Macklon, Kirsten T.

    2016-01-01

    Introduction Fertility counselling for young women newly diagnosed with cancer is an important field of preconceptional counselling. This qualitative, small-scale study explored how young women newly diagnosed with cancer experienced specialized fertility preservation counselling and treatment in the public Danish health care system. Methods Semi-structured, in-depth interviews were conducted with five women below 40 years recently diagnosed with cancer. All women received fertility counselli...

  13. Sexual function and fertility issues in cases of exstrophy epispadias complex

    Directory of Open Access Journals (Sweden)

    M S Ansari

    2010-01-01

    Full Text Available In patients with EEC, the issues such as sexuality, sexual function and fertility gain more importance once theses patients advance from puberty to adulthood. The aim of this review is to critically examine the available evidence on these issues. A systemic literature search was performed in Medline over the last 25 years using the key words: Exstrophy, sexual function and pregnancy. Search results were limited to studies of patients with exstrophy published in English literature. A total of 1500 publications were found and subsequently screened by title and when appropriate by abstracts. Of these, 40 publications pertinent to the subject were included for the analysis. The publications were supplemented by an additional 15 publications obtained from their bibliographies. The studies were rated according to the guidelines published by the US department of health and human services. Heterosexuality is usually expressed in both the sexes and most of them have adequate sexual function. Urinary diversion in some series seems to result in better ejaculatory hence fertility outcome in male patients. Recent series have shown equally good results with primary reconstruction. Most of the female patients have normal fertility while male patients have significantly low fertility. Most of the male and female patients with EEC have adequate sexual function. Most of the female patients have normal fertility while most of the male patients have significantly low fertility.

  14. A Multinomial Model of Fertility Choice and Offspring Sex-Ratios in India

    OpenAIRE

    Rubiana Chamarbagwala; Martin Ranger

    2007-01-01

    Fertility decline in developing countries may have unexpected demographic consequences. Although lower fertility improves nutrition, health, and human capital investments for surviving children, little is known about the relationship between fertility outcomes and female-male offspring sex-ratios. Particularly in countries with a cultural preference for sons, like India and China, fertility decline may deteriorate the already imbalanced sex-ratios. We use the fertility histories of over 90,00...

  15. Potato (Solanum tuberosum) greenhouse tuber production as an assay for asexual reproduction effects from herbicides

    Science.gov (United States)

    The present study determined whether young potato plants can be used as an assay to indicate potential effects of pesticides on asexual reproduction. Solanum tuberosum (Russet Burbank) plants were grown from seed pieces in a mineral soil in pots under greenhouse conditions. Plant...

  16. Knowledge about factors that influence fertility among Australians of reproductive age: a population-based survey.

    Science.gov (United States)

    Hammarberg, Karin; Setter, Tracey; Norman, Robert J; Holden, Carol A; Michelmore, Janet; Johnson, Louise

    2013-02-01

    To explore knowledge about the effects on fertility of age, obesity, smoking, and timing of intercourse among Australians of reproductive age. Telephone survey of a representative sample of Australians. Not applicable. Australians aged 18 to 45 years who wish to have a child or another child now or in the future. None. Knowledge about the effect on fertility of age, obesity, smoking, and timing of intercourse. A total of 462 interviews were conducted. The majority of respondents underestimated, by about 10 years, the age at which male and female fertility starts to decline. Only one in four correctly identified that female fertility starts to decline before age 35, and one in three identified that male fertility starts to decline before age 45. Most (59%) were aware that female obesity and smoking affect fertility, but fewer recognized that male obesity (30%) and smoking (36%) also influence fertility. Almost 40% of respondents had inadequate knowledge of when in the menstrual cycle a woman is most likely to conceive. Considerable knowledge gaps about modifiable factors that affect fertility were identified. These are targeted in a national education campaign to promote awareness of factors that influence fertility. Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  17. Sexuality and fertility in women with Addison's disease.

    Science.gov (United States)

    Erichsen, Martina M; Husebye, Eystein S; Michelsen, Trond M; Dahl, Alv A; Løvås, Kristian

    2010-09-01

    Females with primary adrenal insufficiency (Addison's disease) have reduced levels of circulating androgens, which are allegedly important for sexual functioning. The aim was to determine peripheral androgen status, sexual functioning, and birth rates in Addison's disease females. In a postal survey, all 269 females in the Norwegian Addison's registry were invited to complete the Sexual Activity Questionnaire (SAQ) and registration of childbirths. Blood samples were analyzed for 5alpha-androstane-3alpha,17beta-diol-3-glucuronide (3alpha-Diol-G) and compared with blood donor levels. The SAQ scores were compared with 740 age-matched controls from the general population and 234 women subjected to risk-reducing salpingo-oophorectomy. Fertility was estimated as standardized incidence ratio for birth; the expected number of births was estimated from population statistics. The SAQ was completed by 174 (65%) of the Addison's patients. Those not taking DHEA had significantly lower 3alpha-Diol-G levels than blood donors (mean, 0.53 vs. 2.2 ng/ml; P Addison's disease females were equally sexually active as the controls, but they reported significantly higher pleasure and less discomfort. They reported lower pleasure but less discomfort than the risk-reducing salpingo-oophorectomy women. The fertility was significantly reduced in females with Addison's disease; 54 children were born to mothers with established diagnosis (87.5 expected), yielding a standardized incidence ratio for birth of 0.69 (confidence interval, 0.52-0.86). Despite androgen depletion, females with Addison's disease do not report impaired sexuality. The fertility is reduced after the diagnosis is made; the reasons for this remain unknown.

  18. The Effect of Elevated CO2 and Increased Temperature on in Vitro Fertilization Success and Initial Embryonic Development of Single Male:Female Crosses of Broad-Cast Spawning Corals at Mid- and High-Latitude Locations

    Directory of Open Access Journals (Sweden)

    Miriam Schutter

    2015-05-01

    Full Text Available The impact of global climate change on coral reefs is expected to be most profound at the sea surface, where fertilization and embryonic development of broadcast-spawning corals takes place. We examined the effect of increased temperature and elevated CO2 levels on the in vitro fertilization success and initial embryonic development of broadcast-spawning corals using a single male:female cross of three different species from mid- and high-latitude locations: Lyudao, Taiwan (22° N and Kochi, Japan (32° N. Eggs were fertilized under ambient conditions (27 °C and 500 μatm CO2 and under conditions predicted for 2100 (IPCC worst case scenario, 31 °C and 1000 μatm CO2. Fertilization success, abnormal development and early developmental success were determined for each sample. Increased temperature had a more profound influence than elevated CO2. In most cases, near-future warming caused a significant drop in early developmental success as a result of decreased fertilization success and/or increased abnormal development. The embryonic development of the male:female cross of A. hyacinthus from the high-latitude location was more sensitive to the increased temperature (+4 °C than the male:female cross of A. hyacinthus from the mid-latitude location. The response to the elevated CO2 level was small and highly variable, ranging from positive to negative responses. These results suggest that global warming is a more significant and universal stressor than ocean acidification on the early embryonic development of corals from mid- and high-latitude locations.

  19. Whole ovary cryopreservation with vascular transplantation – A future development in female oncofertility

    Directory of Open Access Journals (Sweden)

    Mats Brännström

    2010-07-01

    Full Text Available Preservation of female fertility in female cancer victims is gaining more importance in the light of the excellent survival rates today after treatment for the types of cancer, which are common in women during childhood and fertile age. In this article we discuss the risks of infertility after various cancer treatments and in what patient categories fertility preservation should be discussed. The modes of female fertility preservation used today as clinically established methods or as experimental methods that are used in the human female are reviewed. The advantages and disadvantages of the methods are also identified. Whole ovary cryopreservation has been suggested as a possible future more efficient method of fertility preservation. The research on this method in different animal models is discussed in detail and unsolved questions are identified. To date there has not been any attempt to transplant a cryopreserved whole human ovary but human ovaries have already been cryopreserved for future fertility preservation purposes, when cryobiological and microsurgical techniques have been further refined.

  20. Effects of functionally asexual reproduction on quantitative genetic variation in the evening primroses (Oenothera, Onagraceae).

    Science.gov (United States)

    Godfrey, Ryan M; Johnson, Marc T J

    2014-11-01

    It has long been predicted that a loss of sexual reproduction leads to decreased heritable variation within populations and increased differentiation between populations. Despite an abundance of theory, there are few empirical tests of how sex affects genetic variation in phenotypic traits, especially for plants. Here we test whether repeated losses of two critical components of sex (recombination and segregation) in the evening primroses (Oenothera L., Onagraceae) affect quantitative genetic variation within and between populations. We sampled multiple genetic families from 3-5 populations from each of eight Oenothera species, which represented four independent transitions between sexual reproduction and a functionally asexual genetic system called "permanent translocation heterozygosity." We used quantitative genetics methods to partition genetic variation within and between populations for eight plant traits related to growth, leaf physiology, flowering, and resistance to herbivores. Heritability was, on average, 74% higher in sexual Oenothera populations than in functionally asexual populations, with plant growth rate, specific leaf area, and the percentage of leaf water content showing the strongest differences. By contrast, genetic differentiation among populations was 2.8× higher in functionally asexual vs. sexual Oenothera species. This difference was particularly strong for specific leaf area. Sexual populations tended to exhibit higher genetic correlations among traits, but this difference was weakly supported. These results support the prediction that sexual reproduction maintains higher genetic variation within populations, which may facilitate adaptive evolution. We also found partial support for the prediction that a loss of sex leads to greater population differentiation, which may elevate speciation rates. © 2014 Botanical Society of America, Inc.

  1. Barriers to Managing Fertility: Findings From the Understanding Fertility Management in Contemporary Australia Facebook Discussion Group

    Science.gov (United States)

    Rowe, Heather

    2016-01-01

    Background As part of research investigating the complexities of managing fertility in Australia, public opinions about how Australians manage their fertility were sought from women and men. Objective To identify public opinion about sexual and reproductive health in Australia. Methods To ensure access to a diverse group of people throughout Australia, an online group was advertised and convened on Facebook from October through December 2013. In a closed-group moderated discussion, participants responded to questions about how people in Australia attempt to manage three aspects of fertility: avoiding pregnancy, achieving pregnancy, and difficulties conceiving. Nonidentifiable demographic information was sought; no personal accounts of fertility management were requested. The discussion transcript was analyzed thematically. Results There were 61 female and 2 male Facebook users aged 18 to 50 years living in Australia participating in the study. Four main themes about fertility management were identified: access, geographical location, knowledge, and cost. Participants reported that young people and people from rural areas face barriers accessing contraception and fertility services. Limited knowledge about sex and reproduction and the cost of fertility services and contraception were also said to impede effective fertility management. Conclusions Reasons for inequalities in effective fertility management that are amenable to change were identified. Facebook is an effective method for gaining insights into public opinion about sexual and reproductive health. PMID:26878865

  2. Mitochondrial functionality in female reproduction

    Directory of Open Access Journals (Sweden)

    Łukasz Gąsior

    2017-01-01

    Full Text Available In most animal species female germ cells are the source of mitochondrial genome for the whole body of individuals. As a source of mitochondrial DNA for future generations the mitochondria in the female germ line undergo dynamic quantitative and qualitative changes. In addition to maintaining the intact template of mitochondrial genome from one generation to another, mitochondrial role in oocytes is much more complex and pleiotropic. The quality of mitochondria determines the ability of meiotic divisions, fertilization ability, and activation after fertilization or sustaining development of a new embryo. The presence of normal number of functional mitochondria is also crucial for proper implantation and pregnancy maintaining. This article addresses issues of mitochondrial role and function in mammalian oocyte and presents new approaches in studies of mitochondrial function in female germ cells.

  3. Intrauterine Exposure to Paracetamol and Aniline Impairs Female Reproductive Development by Reducing Follicle Reserves and Fertility

    DEFF Research Database (Denmark)

    Holm, Jacob Bak; Mazaud-Guittot, Severine; Danneskiold-Samsøe, Niels Banhos

    2016-01-01

    in shortening of the anogenital distance in adult offspring, suggesting that fetal hormone signaling had been disturbed. Female offspring of paracetamol-exposed mothers had ovaries with diminished follicle reserve and reduced fertility. Fetal gonads of exposed animals had also reduced gonocyte numbers......, suggesting that the reduced follicle count in adults could be due to early disruption of germ cell development. However, ex vivo cultures of ovaries from 12.5 days post coitum fetuses showed no decrease in proliferation or expression following exposure to paracetamol. This suggests that the effect...... of paracetamol occurs prior to this developmental stage. Accordingly, using embryonic stem cells as a proxy for primordial germ cells we show that paracetamol is an inhibitor of cellular proliferation, but without cytotoxic effects. Collectively, our data show that intrauterine exposure to paracetamol at levels...

  4. Swedish high school students' knowledge and attitudes regarding fertility and family building

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    Ekelin Maria

    2012-03-01

    Full Text Available Abstract Background Infertility is a serious problem for those who suffer. Some of the risks for infertility are preventable and the individual should therefore have knowledge of them. The purposes of this study were to investigate high-school students' knowledge about fertility, plans for family building and to compare views and knowledge between female and male students. Methods A questionnaire containing 34 items was answered by 274 students. Answers from male and female students were compared using student's t-test for normally distributed variables and Mann-Whitney U-test for non-normal distributions. The chi-square test was used to compare proportions of male and female students who answered questions on nominal and ordinal scales. Differences were considered as statistically significant at a p-value of 0.05. Results Analyses showed that 234 (85% intended to have children. Female students felt parenthood to be significantly more important than male students: p = 0.01. The mean age at which the respondents thought they would like to start to build their family was 26 (± 2.9 years. Men believed that women's fertility declined significantly later than women did: p = 0.01. Women answered that 30.7% couples were involuntarily infertile and men answered 22.5%: p = 0.01. Females thought it significantly more likely that they would consider IVF or adoption than men, p = 0.01. Men felt they were more likely to abstain from having children than women: p = 0.01. Women believed that body weight influenced fertility significantly more often than men: p = 0.01 and men believed significantly more often that smoking influenced fertility: p = 0.03. Both female and male students answered that they would like to have more knowledge about the area of fertility. Conclusions Young people plan to start their families when the woman's fertility is already in decline. Improving young people's knowledge about these issues would give them more opportunity to take

  5. Should access to fertility treatment be determined by female body mass index?

    Science.gov (United States)

    Pandey, S; Maheshwari, A; Bhattacharya, S

    2010-04-01

    Resource allocation towards fertility treatment has been extensively debated in countries where fertility treatment is publicly-funded. Medical, social and ethical aspects have been evaluated prior to allocation of resources. Analysis of cost-effectiveness, risks and benefits and poor success rates have led to calls of restricting fertility treatment to obese women. In this debate article, we critically appraise the evidence underlying this issue and highlight the problems with such a policy. Poor success rate of treatment is unsubstantiated as there is insufficient evidence to link high body mass index (BMI) to reduction in live birth. Obstetric complications have a linear relationship with BMI but are significantly influenced by maternal age. The same is true for miscarriage rates which are influenced by the confounding factors of polycystic ovary syndrome and age. Studies have shown that the direct costs per live birth are no greater for overweight and obese women. With changing demographics over half the reproductive-age population is overweight or obese. Restricting fertility treatment on the grounds of BMI would cause stigmatization and lead to inequity, feelings of injustice and social tension as affluent women manage to bypass these draconian restrictions. Time lost and poor success of conventional weight loss strategies would jeopardize the chances of conception for many women.

  6. No detectable fertility benefit from a single additional mating in wild stalk-eyed flies.

    Directory of Open Access Journals (Sweden)

    Elisabeth Harley

    2010-12-01

    Full Text Available Multiple mating by female insects is widespread, and the explanation(s for repeated mating by females has been the subject of much discussion. Females may profit from mating multiply through direct material benefits that increase their own reproductive output, or indirect genetic benefits that increase offspring fitness. One particular direct benefit that has attracted significant attention is that of fertility assurance, as females often need to mate multiply to achieve high fertility. This hypothesis has never been tested in a wild insect population.Female Malaysian stalk-eyed flies (Teleopsis dalmanni mate repeatedly during their lifetime, and have been shown to be sperm limited under both laboratory and field conditions. Here we ask whether receiving an additional mating alleviates sperm limitation in wild females. In our experiment one group of females received a single additional mating, while a control group received an interrupted, and therefore unsuccessful, mating. Females that received an additional mating did not lay more fertilised eggs in total, nor did they lay proportionately more fertilised eggs. Female fertility declined significantly through time, demonstrating that females were sperm limited. However, receipt of an additional mating did not significantly alter the rate of this decline.Our data suggest that the fertility consequences of a single additional mating were small. We discuss this effect (or lack thereof, and suggest that it is likely to be attributed to small ejaculate size, a high proportion of failed copulations, and the presence of X-linked meiotic drive in this species.

  7. Distribution of Phoxinus eos, Phoxinus neogaeus, and their asexually-reproducing hybrids (Pisces: Cyprinidae in Algonquin Provincial Park, Ontario.

    Directory of Open Access Journals (Sweden)

    Jonathan A Mee

    Full Text Available Hybrid Phoxinus are one of the few asexually reproducing vertebrates species. The distribution of hybrid Phoxinus among lakes in Algonquin Park, Ontario, was evaluated relative to the distribution of parental species and relative to physiochemical lake characteristics. No association between the distribution of hybrids and the distribution of parental species was found, suggesting that the hybrids can successfully coexist with either parental species. In addition, we found no association between hybrid distribution and the physiochemical characteristics of lakes, suggesting that the hybrids are generalists with respect to the ecological niches available in Algonquin Park. There was a difference between the physiochemical characteristics of lakes with and without the parental species P. neogaeus. The lakes containing P. neogaeus were lower elevation than the lakes containing the other parental species, P. eos. The difference in distribution between the parental species may therefore be due to different dispersal abilities, to later arrival following post-glacial dispersal, or to differences in ecology. These results suggest that asexual reproduction is a successful strategy for hybrid Phoxinus in Algonquin Park because these sperm-dependent asexual hybrids are able to survive and persist regardless of which parental species is present, and regardless of the physiochemical characteristics of their habitat.

  8. Fertility in Alberta in a Context of Rapid Economic Growth, 1997-2007

    Directory of Open Access Journals (Sweden)

    Frank Trovato

    2010-01-01

    Full Text Available Historically, birth rates in Alberta have followed closely the trajectory of change experienced by the other Canadian provinces. Its total fertility rate fell during the low point of the 1930s; it increased during the post-War baby boom in the 1950s and sixties, and thereafter fell to sub-replacement levels beginning in the mid 1970s. In recent years, especially since the early 2000s, the birth rate in Alberta has unexpectedly increased, such that by 2007, it had reached 1.90 children per woman---not far from the 2.1 level needed for generational replacement in the long term. During this same period both national and provincial fertility rates fluctuated at levels below those of Alberta (except Saskatchewan and Manitoba, whose rates have been higher. In this study, I examine the historical pattern of fertility change in Alberta, noting similarities and differences with the other provinces. I then look at the association of selected macro level factors (marriage, unemployment, wages, female labour force participation with change in total and parity-specific birth rates between 1997 and 2007, a period of unprecedented economic growth in Alberta. The statistical results show that although marriage is not significantly correlated with change in fertility rates, male and female wages and female labour force participation all show associations consistent with a procyclical interpretation of fertility change --- that is, periods of economic growth are conducive to fertility increase whereas bad economic times lead to reduced fertility.

  9. Fertility in Alberta in a Context of Rapid Economic Growth, 1997-2007

    Directory of Open Access Journals (Sweden)

    Frank Trovato

    2010-12-01

    Full Text Available Historically, birth rates in Alberta have followed closely the trajectory of change experienced by the other Canadian provinces. Its total fertility rate fell during the low point of the 1930s; it increased during the post-War baby boom in the 1950s and sixties, and thereafter fell to subreplacement levels beginning in the mid 1970s. In recent years, especially since the early 2000s, the birth rate in Alberta has unexpectedly increased, such that by 2007, it had reached 1.90 children per woman - not far from the 2.1 level needed for generational replacement in the long term. During this same period both national and provincial fertility rates fluctuated at levels below those of Alberta (except Saskatchewan and Manitoba, whose rates have been higher. In this study, I examine the historical pattern of fertility change in Alberta, noting similarities and differences with the other provinces. I then look at the association of selected macro level factors (marriage, unemployment, wages, female labour force participation with change in total and parity-specific birth rates between 1997 and 2007, a period of unprecedented economic growth in Alberta. The statistical results show that although marriage is not significantly correlated with change in fertility rates, male and female wages and female labour force participation all show associations consistent with a procyclical interpretation of fertility change - that is, periods of economic growth are conducive to fertility increase whereas bad economic times are associated with reduced fertility.

  10. The Drosophila Su(var)3-7 gene is required for oogenesis and female fertility, genetically interacts with piwi and aubergine, but impacts only weakly transposon silencing.

    Science.gov (United States)

    Basquin, Denis; Spierer, Anne; Begeot, Flora; Koryakov, Dmitry E; Todeschini, Anne-Laure; Ronsseray, Stéphane; Vieira, Cristina; Spierer, Pierre; Delattre, Marion

    2014-01-01

    Heterochromatin is made of repetitive sequences, mainly transposable elements (TEs), the regulation of which is critical for genome stability. We have analyzed the role of the heterochromatin-associated Su(var)3-7 protein in Drosophila ovaries. We present evidences that Su(var)3-7 is required for correct oogenesis and female fertility. It accumulates in heterochromatic domains of ovarian germline and somatic cells nuclei, where it co-localizes with HP1. Homozygous mutant females display ovaries with frequent degenerating egg-chambers. Absence of Su(var)3-7 in embryos leads to defects in meiosis and first mitotic divisions due to chromatin fragmentation or chromosome loss, showing that Su(var)3-7 is required for genome integrity. Females homozygous for Su(var)3-7 mutations strongly impair repression of P-transposable element induced gonadal dysgenesis but have minor effects on other TEs. Su(var)3-7 mutations reduce piRNA cluster transcription and slightly impact ovarian piRNA production. However, this modest piRNA reduction does not correlate with transposon de-silencing, suggesting that the moderate effect of Su(var)3-7 on some TE repression is not linked to piRNA production. Strikingly, Su(var)3-7 genetically interacts with the piwi and aubergine genes, key components of the piRNA pathway, by strongly impacting female fertility without impairing transposon silencing. These results lead us to propose that the interaction between Su(var)3-7 and piwi or aubergine controls important developmental processes independently of transposon silencing.

  11. High-dose radioiodine treatment for differentiated thyroid carcinoma is not associated with change in female fertility or any genetic risk to the offspring

    International Nuclear Information System (INIS)

    Bal, Chandrasekhar; Kumar, Ajay; Tripathi, Madhavi; Chandrashekar, Narayana; Phom, Hentok; Murali, Nadig R.; Chandra, Prem; Pant, Gauri S.

    2005-01-01

    Background: We tried to evaluate the female fertility and genetic risk to the offspring from the exposure to high-dose 131 I by assessing the pregnancy outcomes and health status of the children of female patients with differentiated thyroid cancer who had received therapeutic doses of 131 I. Materials and Methods: From 1967 to 2002, a total of 1,282 women had been treated with 131 I. Of these patients, 692 (54%) were in the reproductive age group (18-45 years). Forty women had a total of 50 pregnancies after high-dose 131 I. Age at presentation ranged from 16 to 36 years (mean, 23 ± 4 years). Histopathology was papillary thyroid cancer in 32 cases and follicular thyroid cancer in 8 cases. Results: Single high-dose therapy was given in 30 cases, 2 doses were given in 7 cases, 3 doses were given in 2 cases, and four doses were given in 1 case in which lung metastases had occurred. In 37 patients (92%), disease was successfully ablated before pregnancy. Ovarian absorbed-radiation dose calculated by the MIRD method ranged from 3.5 to 60 cGy (mean, 12 ± 11 cGy). The interval between 131 I therapy and pregnancy varied from 7 to 120 months (37.4 ± 28.2 months). Three spontaneous abortions occurred in 2 women. Forty-seven babies (20 females and 27 males) were born. Forty-four babies were healthy with normal birth weight and normal developmental milestones. Twenty women delivered their first baby after 131 I therapy. The youngest child in our series is 11 months of age, and the oldest is 8.5 years of age. Conclusions: Female fertility is not affected by high-dose radioiodine treatment, and the therapy does not appear to be associated with any genetic risks to the offspring

  12. Data from: Natural epigenetic variation contributes to heritable flowering divergence in a widespread asexual dandelion lineage

    NARCIS (Netherlands)

    Wilschut, Rutger; Oplaat, C.; Snoek, L.B.; Kirschner, J.; Verhoeven, K.J.F.

    2015-01-01

    Epigenetic variation has been proposed to contribute to the success of asexual plants, either as a contributor to phenotypic plasticity or by enabling transient adaptation via selection on transgenerationally stable, but reversible, epialleles. While recent studies in experimental plant populations

  13. Marijuana, the Endocannabinoid System and the Female Reproductive System

    OpenAIRE

    Brents, Lisa K.

    2016-01-01

    Marijuana use among women is highly prevalent, but the societal conversation on marijuana rarely focuses on how marijuana affects female reproduction and endocrinology. This article reviews the current scientific literature regarding marijuana use and hypothalamic-pituitary-ovarian (HPO) axis regulation, ovarian hormone production, the menstrual cycle, and fertility. Evidence suggests that marijuana can reduce female fertility by disrupting hypothalamic release of gonadotropin releasing hormo...

  14. Sperm storage and duration of fertility in female ostriches ( Struthio ...

    African Journals Online (AJOL)

    , the duration of sperm storage and the fertile period following separation of sexes were investigated by egg break-out and by counting the sperm in the perivitelline membrane (spermOPVL) above the germinal disc (GD) region. Fertilisation ...

  15. Will sex selection reduce fertility?

    Science.gov (United States)

    Leung, S F

    1994-01-01

    Population control is one of the primary policies applied against poverty in many low income countries. The widespread prevalence of son preference in some countries such as China and India, however, works against any reduction of fertility. This is so because parents often continue to have children until they obtain the number of sons which they desire. The bias against girls has also led to higher abortion and mortality rates of female children. It is frequently argued that if sex selection methods are made available to parents so that they can control the gender of their children, population growth would be lowered and women's welfare improved. The author investigates both theoretically and numerically the impact of sex selection on fertility. A static quantity-quality model of fertility is used to compare fertility choices when parents cannot choose the gender of children versus a situation in which parents can choose gender. Empirical data are drawn from the 1976 Malaysian Family Life Survey. Analysis found that whether sex selection reduces fertility depends upon the second and third derivatives of the utility function and the child expenditure function. A numerical dynamic analysis is also presented. The simulation shows, using empirical dynamic models of fertility and the Monte Carlo integration technique, that sex selection on the firstborn child among the Chinese in Malaysia could reduce fertility by about 3%.

  16. Nutrition and fertility.

    Science.gov (United States)

    Pinelli, G; Tagliabue, A

    2007-12-01

    The first studies about fertility and nutrition date back to the 70ies and already showed a strict relation among female fertility, weight and body composition. However, the mechanisms of this connection started to be explained only after leptin's discovery. According to some authors' opinion, leptin could interact with reproductive axis at multiple sites with stimulatory effects at the hypothalamus and pituitary and stimulatory or inhibitory actions at the gonads. Leptin could play a role in other physiologic processes such as menstruation and pregnancy, and could initiate the complex process of puberty. It has been showed that conditions in which nutritional status is suboptimal, such as eating disorders, exercise induced amenhorrea, functional hypothalamic amenhorrea and polycystic ovarian syndrome, are associated with abnormal leptin levels. These conditions, are characterized by severe changes in body composition and dietary habits. Since leptin is regulated by body composition and dietary factors, (such as energy intake and macronutrient composition), a strict connection between nutritional intake and fertility regulated by leptin is confirmed. This review focuses on the current knowledge about nutritional factors that influence leptin levels. Since clinical and subclinical nutritional imbalance can determine the development and the maintenance of neuroendocrine and metabolic aberrations, studies on fertility need a deeper attention about dietary habits and nutritional status.

  17. Cytogenetical investigations on fertilization, embriogenesis and fruit formation by irradiated pollen

    International Nuclear Information System (INIS)

    Dryanovska, O.

    1981-01-01

    The mechanism of fertilization pollination with gamma-irradiated pollen (1-500 kR) in plants of various double fertilization: Crepis (Nicotiana tabacum, Lycopersicum esculentum, Solanum melongena, Ornithogalum gramminifolium, Melandrium rubrum) type, Lilium (Lilium speciosum) type, and Trandescantia (Tradescantia paludosa) type was studied, along with the opportunity of its modification, embryogenesis and fruit and seed formation. In the Crepis type, depending on the disturbances of male chromatin, fertilization manifested itself as: 1) normal karyogamy with decondensation of male chromatin and the formation of supplementary nucleoli and further development of embryo and endosperm (1-500 kR); 2) karyogamy without decondensation and functioning of the male chromatin (1-500 kR); 3) karyogamy or sticking the male chromatin to the nuclei of the female sex cells, stimulating the development of the ovule, embryo, and endosperm (50-500 kR); 4) sticking the highly pycnotized male chromatin to the nuclei of the female sex cells without evidence of zygote and endosperm function and further development (50-500 kR). In the Lilium type modification of fertilization was manifested by: 1) normal karyogamy with developing diploid embryos and pentaploid endosperm with aberrations (1-20 kK); 2) sticking the male chromatin to the nuclei of the female sex cells and stimulation of their development (50-500 kR). In the Trandescantia type the irradiated male chromatin modified fertilization as: 1) karyogamy with spermia having fragments, two spermia connected by a bridge or with a generative nucleus with aberrations (1-50 kR); 2) karyogamy without developing the female sex nuclei (10-500kR); 3) karyogamy or sticking the male chromatin to the female sex cell nuclei and stimulation of their development (10-500 kR); 4) sticking the male chromatin with no stimulating effect (10-500 kR). (author)

  18. Couples' fertility decision-making

    Directory of Open Access Journals (Sweden)

    Petra Stein

    2014-06-01

    Full Text Available Background: The decision about whether to start a family within a partnership can be viewed as a result of an interaction process. The influence of each of the partners in a couple differs depending on their individual preferences and intentions towards having children. Both of the partners additionally influence each other's fertility intentions and preferences. Objective: We specify, estimate, and test a model that examines the decision about whether to have a child as a choice that is made jointly by the two partners. The transition to the birth of a (further child is investigated with the explicit consideration of both the female partner and the male partner in the partnership context. Methods: An approach for modelling the interactive influences of the two actors in the decision-making process was proposed. A trivariate distribution consisting of both the female and the male partners' fertility intentions, as well as the joint generative decision, was modelled. A multivariate non-linear probit model was chosen and the problem of identification in estimating the relative effects of the actors was resolved. These parameters were used to assess the relative importance of each of the partners' intentions in the decision. We carried out the analysis with MPLUS. Data from the panel of intimate relationships and family dynamics (pairfam was used to estimate the model. Results: The biographical context of each of the partners in relation to their own as well as to their partner's fertility intentions was found to be of considerable importance. Of the significant individual and partner effects, the male partner was shown to have the greater influence. But the female partner was found to have stronger parameters overall and she ultimately has a veto power in the couple's final decision.

  19. Age- and size-dependent mating performance and fertility in a pelagic copepod, Temora longicornis

    DEFF Research Database (Denmark)

    Sichlau, Mie Hylstofte; Kiørboe, Thomas

    2011-01-01

    Prepress abstract: In many species, size and age have been shown to be strong determinants of the reproductive success for both sexes. Here we examine age- and size dependent reproductive performance (egg- and sperm production, mating success) in a pelagic copepod. Compared to smaller males, larger...... males produce larger spermatophores containing more spermatozoa, and fertilize a larger fraction of available females. Females mating with large males produce more offspring than those mating with small males. Similarly, large females have higher egg production rates as well as a higher life-time egg...... fertilize females for only about eight days after they mature. The strong size- and age-dependent fertility observed in this species is conducive to the development of sexual selection via mate choice for young and large partners, as has been shown in one other copepod species...

  20. Physicians' self-reported practice behaviour regarding fertility-related discussions in paediatric oncology in Sweden.

    Science.gov (United States)

    Armuand, G M; Nilsson, J; Rodriguez-Wallberg, K A; Malmros, J; Arvidson, J; Lampic, C; Wettergren, L

    2017-10-01

    The aim of this study was to investigate practice behaviours of Swedish physicians with regard to discussing the impact of cancer treatment on fertility with paediatric oncology patients and their parents, and to identify factors associated with such discussions. A cross-sectional survey study was conducted targeting all physicians in Sweden working in paediatric oncology care settings. Participants responded to a questionnaire measuring practice behaviour, attitudes, barriers, and confidence in knowledge. Multivariable logistic regression was used to determine factors associated with seldom discussing fertility. More than half of the physicians routinely talked with their patients/parents about the treatment's potential impact on fertility (male patients: 62%; female patients: 57%; P = 0.570). Factors associated with less frequently discussing fertility with patients/parents were working at a non-university hospital (male patients: OR 11.49, CI 1.98-66.67; female patients: OR 33.18, CI 4.06-271.07), concerns that the topic would cause worry (male patients: OR 8.23, CI 1.48-45.89; female patients: OR 12.38, CI 1.90-80.70), and perceiving the parents as anxious (male patients: OR 7.18, CI 1.20-42.85; female patients: OR 11.65, CI 1.32-103.17). Based on our findings, we recommend structured training in how to communicate about fertility issues in stressful situations, which in turn might increase fertility-related discussions in paediatric oncology. © 2017 The Authors. Psycho-Oncology published by John Wiley & Sons Ltd.

  1. Dynamic formation of asexual diploid and polyploid lineages: multilocus analysis of Cobitis reveals the mechanisms maintaining the diversity of clones.

    Directory of Open Access Journals (Sweden)

    Karel Janko

    Full Text Available Given the hybrid genomic constitutions and increased ploidy of many asexual animals, the identification of processes governing the origin and maintenance of clonal diversity provides useful information about the evolutionary consequences of interspecific hybridization, asexuality and polyploidy. In order to understand the processes driving observed diversity of biotypes and clones in the Cobitis taenia hybrid complex, we performed fine-scale genetic analysis of Central European hybrid zone between two sexual species using microsatellite genotyping and mtDNA sequencing. We found that the hybrid zone is populated by an assemblage of clonally (gynogenetically reproducing di-, tri- and tetraploid hybrid lineages and that successful clones, which are able of spatial expansion, recruit from two ploidy levels, i.e. diploid and triploid. We further compared the distribution of observed estimates of clonal ages to theoretical distributions simulated under various assumptions and showed that new clones are most likely continuously recruited from ancestral populations. This suggests that the clonal diversity is maintained by dynamic equilibrium between origination and extinction of clonal lineages. On the other hand, an interclonal selection is implied by nonrandom spatial distribution of individual clones with respect to the coexisting sexual species. Importantly, there was no evidence for sexually reproducing hybrids or clonally reproducing non-hybrid forms. Together with previous successful laboratory synthesis of clonal Cobitis hybrids, our data thus provide the most compelling evidence that 1 the origin of asexuality is causally linked to interspecific hybridization; 2 successful establishment of clones is not restricted to one specific ploidy level and 3 the initiation of clonality and polyploidy may be dynamic and continuous in asexual complexes.

  2. Batch fertility and larval parameters of the jaguar cichlid (Cichlasoma managuense spawned in the laboratory (ESP

    Directory of Open Access Journals (Sweden)

    Jorge Günther Nonell

    2016-03-01

    Full Text Available Batch fertility and larval parameters of 32 spawns of the jaguar guapote (Cichlasoma managuense in the laboratory were analyzed. Batch fertility was positively correlated with the female weight with spawns between about 3000 to 6000 larvae for females between 100 and 500 g wet weight. No significant correlation was found between larval parameters (fresh weight and % dry weight and female weight.

  3. Male sexual ornament size is positively associated with reproductive morphology and enhanced fertility in the stalk-eyed fly Teleopsis dalmanni

    Directory of Open Access Journals (Sweden)

    Chapman Tracey

    2008-08-01

    Full Text Available Abstract Background Exaggerated male ornaments and displays often evolve in species where males only provide females with ejaculates during reproduction. Although "good genes" arguments are typically invoked to explain this phenomenon, a simpler alternative is possible if variation in male reproductive quality (e.g. sperm number, ejaculate content, mating rate is an important determinant of female reproductive success. The "phenotype-linked fertility hypothesis" states that female preference for male ornaments or displays has been selected to ensure higher levels of fertility and has driven the evolution of exaggerated male traits. Females of the stalk-eyed fly Teleopsis dalmanni must mate frequently to maintain high levels of fertility and prefer to mate with males exhibiting large eyespan, a condition-dependent sexual ornament. If eyespan indicates male reproductive quality, females could directly increase their reproductive success by mating with males with large eyespan. Here we investigate whether male eyespan indicates accessory gland and testis length, and then ask whether mating with large eyespan males affects female fertility. Results Male eyespan was a better predictor of two key male reproductive traits – accessory gland and testis length – than was body size alone. This positive relationship held true over three levels of increasing environmental stress during the maturation of the adult accessory glands and testes. Furthermore, females housed with a large eyespan male exhibited higher levels of fertility than those with small eyespan males. Conclusion Male eyespan in stalk-eyed flies is subject to strong directional mate preference and is a reliable indicator of male reproductive quality – both because males with larger eyespan have bigger accessory glands and testes, and also as they confer higher fertility on females. Fertility enhancement may have arisen because males with larger eyespan mated more often and/or because

  4. Female infertility

    International Nuclear Information System (INIS)

    Hall, D.A.; Yoder, I.

    1984-01-01

    Infertility, defined as 1 year of unprotected intercourse without conception, is becoming of increasingly important medical concern. Fertility in both the male and the female is at its peak in the twenties. Many couples today have postponed marriage and/or childbearing into their 30s until careers are established, but at that point fertility may be diminished. The current epidemic of venereal disease has been associated with an increasing incidence of tubal scarring. In addition, the use of intrauterine devices (IUDs) and birth control pills for contraception have let to later problems with pelvic inflammatory disease (PID) and ovulation disturbances. The problem of infertility intensifies as the number of babies available for adoption decreases. Therefore, it is estimated that approximately 10-20% of couples will eventually seek medical attention for an infertility-related problem. Fortunately, marked improvements in the results of tubal surgery are concurrently occurring secondary to refinements in microsurgical techniques, and many medical alternatives to induce ovulation are being developed. The male factor causes infertility in 30-40 % of couples, and the female factor is responsible in approximately 50% of couples. No cause is found in 10-20% of couples. This chapter discusses the role of coordinated imaging in the diagnosis and therapy of infertility in the female

  5. Asexual queen succession mediates an accelerated colony life cycle in the termite Silvestritermes minutus

    Czech Academy of Sciences Publication Activity Database

    Fougeyrollas, R.; Křivánek, Jan; Roy, V.; Dolejšová, Klára; Frechault, S.; Roisin, Y.; Hanus, Robert; Sillam-Dusses, D.

    2017-01-01

    Roč. 26, č. 12 (2017), s. 3295-3308 ISSN 0962-1083 R&D Projects: GA ČR(CZ) GA14-12774S Institutional support: RVO:61388963 Keywords : asexual queen succession * breeding system * life history * parthenogenesis * Silvestritermes minutus * termites Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Genetics and heredity (medical genetics to be 3) Impact factor: 6.086, year: 2016

  6. High-fertility phenotypes: two outbred mouse models exhibit substantially different molecular and physiological strategies warranting improved fertility.

    Science.gov (United States)

    Langhammer, Martina; Michaelis, Marten; Hoeflich, Andreas; Sobczak, Alexander; Schoen, Jennifer; Weitzel, Joachim M

    2014-01-01

    Animal models are valuable tools in fertility research. Worldwide, there are more than 400 transgenic or knockout mouse models available showing a reproductive phenotype; almost all of them exhibit an infertile or at least subfertile phenotype. By contrast, animal models revealing an improved fertility phenotype are barely described. This article summarizes data on two outbred mouse models exhibiting a 'high-fertility' phenotype. These mouse lines were generated via selection over a time period of more than 40 years and 161 generations. During this selection period, the number of offspring per litter and the total birth weight of the entire litter nearly doubled. Concomitantly with the increased fertility phenotype, several endocrine parameters (e.g. serum testosterone concentrations in male animals), physiological parameters (e.g. body weight, accelerated puberty, and life expectancy), and behavioral parameters (e.g. behavior in an open field and endurance fitness on a treadmill) were altered. We demonstrate that the two independently bred high-fertility mouse lines warranted their improved fertility phenotype using different molecular and physiological strategies. The fertility lines display female- as well as male-specific characteristics. These genetically heterogeneous mouse models provide new insights into molecular and cellular mechanisms that enhance fertility. In view of decreasing fertility in men, these models will therefore be a precious information source for human reproductive medicine. Translated abstract A German translation of abstract is freely available at http://www.reproduction-online.org/content/147/4/427/suppl/DC1.

  7. Male meiosis in Crustacea: synapsis, recombination, epigenetics and fertility in Daphnia magna.

    Science.gov (United States)

    Gómez, Rocío; Van Damme, Kay; Gosálvez, Jaime; Morán, Eugenio Sánchez; Colbourne, John K

    2016-09-01

    We present the first detailed cytological study of male meiosis in Daphnia (Crustacea: Branchiopoda: Cladocera)-an aquatic microcrustacean with a cyclical parthenogenetic life cycle. Using immunostaining of the testes in Daphnia magna for baseline knowledge, we characterized the different stages of meiotic division and spermiogenesis in relation to the distribution of proteins involved in synapsis, early recombination events and sister chromatid cohesion. We also studied post-translational histone modifications in male spermatocytes, in relation to the dynamic chromatin progression of meiosis. Finally, we applied a DNA fragmentation test to measure sperm quality of D. magna, with respect to levels of inbreeding. As a proxy for fertility, this technique may be used to assess the reproductive health of a sentinel species of aquatic ecosystems. Daphnia proves to be a model species for comparative studies of meiosis that is poised to improve our understanding of the cytological basis of sexual and asexual reproduction.

  8. Fertility preservation for medical reasons in girls and women: British fertility society policy and practice guideline.

    Science.gov (United States)

    Yasmin, Ephia; Balachandren, Neerujah; Davies, Melanie C; Jones, Georgina L; Lane, Sheila; Mathur, Raj; Webber, Lisa; Anderson, Richard A

    2018-04-01

    Fertility preservation in the female poses several challenges due to the invasive nature of the techniques available to achieve it. The guideline aims to bring together the evidence available for the measures for fertility preservation and their outcome. The guideline addresses fertility preservation for medical reasons and includes both oncological and non-oncological causes. The techniques that the guideline considers are: (i) embryo and oocyte cryopreservation; (ii) ovarian tissue cryopreservation; (iii) GnRH agonist suppression and (iv) ovarian transposition. Although ovarian tissue cryopreservation is still considered experimental, the availability of this technique is gaining momentum as more live births from auto-transplanted tissue are reported. The guideline also highlights use of current treatment modalities for benign and malignant conditions that have a better fertility sparing profile. The guideline recommends a multidisciplinary approach in counselling women and girls about the risk to their fertility and available techniques. The role of psychological support in assisting women and girls with decision-making is highlighted. The guideline also highlights the risks associated with these techniques. Women need to be medically fit to undergo invasive procedures. Fertility preservation techniques are appropriate when treatment has curative intent. Fertility preservation is a subject of on-going research on outcomes of different techniques and at the time of publication, studies are still likely to emerge adding to the available literature.

  9. Cryopreservation of ovarian tissue for fertility preservation in young female oncological patients

    DEFF Research Database (Denmark)

    Andersen, Claus Yding; Kristensen, Stine Gry; Greve, Tine

    2012-01-01

    Girls and women suffering from a cancer that requires treatment with gonadotoxic drugs may experience cessation of reproductive function as a side effect due to obliteration of the ovarian pool of follicles. Techniques are now available for fertility preservation, such as cryopreservation of mature...... and growth of follicles, giving rise to menstrual cycles and hormone production for several years. Worldwide, the procedure has resulted in the birth of 15 healthy children. Many cancer patients including girls and young women want fertility preservation, and the techniques are now being further developed...

  10. Widespread occurrence of lysine methylation in Plasmodium falciparum proteins at asexual blood stages.

    Science.gov (United States)

    Kaur, Inderjeet; Zeeshan, Mohammad; Saini, Ekta; Kaushik, Abhinav; Mohmmed, Asif; Gupta, Dinesh; Malhotra, Pawan

    2016-10-20

    Post-transcriptional and post-translational modifications play a major role in Plasmodium life cycle regulation. Lysine methylation of histone proteins is well documented in several organisms, however in recent years lysine methylation of proteins outside histone code is emerging out as an important post-translational modification (PTM). In the present study we have performed global analysis of lysine methylation of proteins in asexual blood stages of Plasmodium falciparum development. We immunoprecipitated stage specific Plasmodium lysates using anti-methyl lysine specific antibodies that immunostained the asexual blood stage parasites. Using liquid chromatography and tandem mass spectrometry analysis, 570 lysine methylated proteins at three different blood stages were identified. Analysis of the peptide sequences identified 605 methylated sites within 422 proteins. Functional classification of the methylated proteins revealed that the proteins are mainly involved in nucleotide metabolic processes, chromatin organization, transport, homeostatic processes and protein folding. The motif analysis of the methylated lysine peptides reveals novel motifs. Many of the identified lysine methylated proteins are also interacting partners/substrates of PfSET domain proteins as revealed by STRING database analysis. Our findings suggest that the protein methylation at lysine residues is widespread in Plasmodium and plays an important regulatory role in diverse set of the parasite pathways.

  11. Fertilization Mechanisms in Flowering Plants.

    Science.gov (United States)

    Dresselhaus, Thomas; Sprunck, Stefanie; Wessel, Gary M

    2016-02-08

    Compared with the animal kingdom, fertilization is particularly complex in flowering plants (angiosperms). Sperm cells of angiosperms have lost their motility and require transportation as a passive cargo by the pollen tube cell to the egg apparatus (egg cell and accessory synergid cells). Sperm cell release from the pollen tube occurs after intensive communication between the pollen tube cell and the receptive synergid, culminating in the lysis of both interaction partners. Following release of the two sperm cells, they interact and fuse with two dimorphic female gametes (the egg and the central cell) forming the major seed components embryo and endosperm, respectively. This process is known as double fertilization. Here, we review the current understanding of the processes of sperm cell reception, gamete interaction, their pre-fertilization activation and fusion, as well as the mechanisms plants use to prevent the fusion of egg cells with multiple sperm cells. The role of Ca(2+) is highlighted in these various processes and comparisons are drawn between fertilization mechanisms in flowering plants and other eukaryotes, including mammals. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Gender equity and fertility intentions in Italy and the Netherlands

    Directory of Open Access Journals (Sweden)

    Maria Letizia Tanturri

    2008-02-01

    Full Text Available Fertility levels have fallen drastically in most industrialized countries. Diverse theoretical and empirical frameworks have had difficulty in explaining these unprecedented low levels of fertility. More recently, however, attention has turned from classic explanations, such as women's increased labour market participation, to gender equity as the essential link to understand this phenomenon. The increase in women's labour market participation did not prompt an increase in men's domestic duties, which is often referred to women's 'dual burden' or 'second shift'. Institutions and policies within countries also facilitate or constrain the combination of women's employment with fertility. This paper provides an empirical test of gender equity theory by examining whether the unequal division of household labour leads to lower fertility intentions of women in different institutional contexts. Italy constitutes a case of high gender inequity, low female labour market participation and the lowest-low fertility. The Netherlands has moderate to low gender inequity, high part-time female labour market participation and comparatively higher fertility. Using data from the 2003 Italian Multipurpose Survey - Family and Social Actors and the 2004/5 Dutch sample from the European Social Survey, a series of logistic regression models test this theory. A central finding is that the unequal division of household labour only has a significant impact on women's fertility intentions when they already carry the load of high paid work hours or children, a finding that is particularly significant for working women in Italy.

  13. A population-based survey on family intentions and fertility awareness in women and men in the United Kingdom and Denmark.

    Science.gov (United States)

    Vassard, Ditte; Lallemant, Camille; Nyboe Andersen, Anders; Macklon, Nick; Schmidt, Lone

    2016-06-27

    Across several European countries family formation is increasingly postponed. The aims of the study were to investigate the desire for family building and fertility awareness in the UK and Denmark. A population-based internet survey was used among women (n = 1,000) and men (n = 237) from the UK (40%) and Denmark (60%). Data covered socio-demographics, family formation, and awareness of female age-related fertility. Data analysis used descriptive statistics and logistic regression analysis for studying associations between low fertility awareness and desired family formation. The majority of all participants desired two or three children. Two-thirds of the childless participants desired a first child at 30+ years, and one-fifth of the women and one-third of the men desired a last child at age 40. Overall, 83% of women and 73% of men were aware that female fertility starts to decline around 25-30 years. Men had significantly lower fertility awareness. Women who underestimated the impact of age on female fertility were significantly more likely to have a desire or attempted their first child at a higher age. Even though the majority were aware of the age-related decrease in female fertility, most desired having children at an age when female fertility has declined. Women who were not sufficiently aware of the impact of advanced age were significantly more likely to have their first child at a higher age. There is a need for developing educational programs for women and men in order to increase the population's knowledge of fertility and risk factors for infertility.

  14. General aspects of fertility and infertility.

    Science.gov (United States)

    Damario, Mark A

    2014-01-01

    Fertility rates have been declining in most Western nations over the past several decades, although it is not entirely clear if an increased rate of infertility substantially contributes to this. As compared to other species, the reproductive efficiency of humans is relatively low. Factors related to fertility include age, exposure to sexually transmitted diseases, frequency of intercourse, coital timing, as well as diet and lifestyle habits. Infertility is considered a disease due to its major disruption of major organ systems and life functions. An infertility evaluation is recommended after 12 months or more of regular, unprotected intercourse and may be considered after 6 months for those female patients over the age of 35 or with other known abnormalities. A proper infertility evaluation is a comprehensive examination of possibly identifiable infertility factors of both female and male partners, lending itself to the most appropriate and potentially effective treatment.

  15. Fertilization failure after IVF in 304 couples

    DEFF Research Database (Denmark)

    Krog, Maria; Prior, Maria; Carlsen, Elisabeth

    2015-01-01

    OBJECTIVES: To identify predictors of total fertilization failure (TFF) and thereby optimize the primary allocation of patients with no well-defined male factor to either IVF or intracytoplasmatic sperm injection (ICSI). Further, to evaluate the long-term fertility prognosis of couples experiencing...... TFF. STUDY DESIGN: A retrospective case-control study including 304 couples with TFF and 304 controls with fertilization after IVF during a 10-year period from year 2000-2010. The controls were the patients with minimum one fertilized oocyte just prior to the cases. Multiple logistic regression...... analysis was used to evaluate the predictors of TFF. RESULTS: The multiple regression analysis identified the following independent predictors of TFF: female smoking, adjusted odds ratio (AOR) 1.7 (95% CI 1.1-2.3), non-tubal factor AOR 2.2 (95% CI 1.5-3.4), progressive motile spermatozoa after preparation...

  16. Subfertility in Women With Rheumatoid Arthritis and the Outcome of Fertility Assessments.

    Science.gov (United States)

    Brouwer, Jenny; Fleurbaaij, Rosalie; Hazes, Johanna M W; Dolhain, Radboud J E M; Laven, Joop S E

    2017-08-01

    Subfertility is frequently encountered among female rheumatoid arthritis (RA) patients and has been associated with disease activity and antirheumatic drugs. However, little is known about the results of the fertility assessments in these women. Our aim was to study the outcome of fertility assessments in subfertile women with RA. A cross-sectional study was performed in a nationwide cohort of female RA patients who were pregnant or trying to conceive between 2002 and 2010 (Pregnancy-Induced Amelioration of Rheumatoid Arthritis Study). Patients who had given consent for future contact (n = 260) received a questionnaire on reproductive history, fertility examinations, and fertility treatments. Medical files were obtained from attending gynecologists. A completed questionnaire was returned by 178 women (68%), of whom 96% had ended their efforts to conceive. Eighty-two subjects (46%) had at least 1 subfertile episode, and for 61 women a diagnosis for subfertility was available. Unexplained subfertility (48%) and anovulation (28%) were the most common gynecologic diagnoses, and both occurred more often in RA patients than reported in the general population. Women with unexplained subfertility more often used nonsteroidal antiinflammatory drugs (NSAIDs) during the periconceptional period. Seventeen percent of all pregnancies were conceived after fertility treatments. Fertility treatments had equal or higher pregnancy rates in RA compared to other subfertile populations. Unexplained subfertility is more often diagnosed in subfertile female RA patients than in the general population, and is related to periconceptional NSAID use. Despite the higher incidence of subfertility in women with RA, the outcome of fertility treatments in these women appears favorable. © 2016 The Authors. Arthritis Care & Research published by Wiley Periodicals, Inc. on behalf of American College of Rheumatology.

  17. The dose effect of irradiated rice pollen on double fertilization

    International Nuclear Information System (INIS)

    Wang Houcong; Chen Zhengming; Chen Ruming; Qiu Simi; Yang Juemin; Yang Huijie

    1995-01-01

    The mature panicles of rice were treated with 60 Co γ-rays in the range of 0∼0.372 kGy. The male sterile line used as the female plants were fertilized with γ-irradiated pollen manually. The dose effect of the irradiated pollen on double fertilization was investigated. It was found that double fertilization of the irradiated pollen was suppressed to different degrees as compared with the control. The effect was noticeable as that the fusion time of the male nucleolus with the female one was delayed with the increasing of γ-radiation dose. The delayed time was less than 13 hours when the dose was below 0.186 kGy and it was more than 15 hours when the dose was above 0.279 kGy. Furthermore, several types of deformed embryonic cells and endosperm nuclei were observed

  18. Child survival and changing fertility patterns in Pakistan.

    Science.gov (United States)

    Sathar, Z A

    1992-01-01

    Pakistan is a country with high fertility and high infant and child mortality, and declines in total mortality and substantial development initiatives. The discussion considers whether fertility patterns in Pakistan can be related to changes in child mortality, and whether current and future changes in fertility influence child survival favorably. Omran's study linked large family size to child survival. Resources, which are divided, become more important deficits in households below the poverty line: a situation common in Pakistan. High fertility is associated with short birth intervals, which are related to higher infant and child mortality. In Pakistan, the spacing and mortality link was found among both poverty and higher socioeconomic households. There is some support for the notion that it is birth weight and general health that are linked to survival rather than competition for resources. Other studies link the maternal age at birth and birth order with child mortality (Alam and Cleland). Trussel argues for limiting births in high risk ages of under 20 years and over 35 years. The exact casual link is not well documented. Institutional and community factors are also considered important in influencing child survival: sanitation, potable water, access to roads, electricity, health and family planning services, and sewage. Young infants are more vulnerable to these factors. Bangladesh and some Indian states have shown that population programs and raising per captia incomes are necessary to fertility decline. In India, female autonomy, access to education, and more equal income distribution were considered more important than economic development to child survival. In Pakistan, Sathar and Kazi have linked at least 2 years of elementary, maternal education with reductions in child mortality. The pervasiveness of female illiteracy hinders the chances of child survival. Sex preferences also impact on female children. The probably impacts of declines in breast

  19. The beginning of a seed: regulatory mechanisms of double fertilization.

    Science.gov (United States)

    Bleckmann, Andrea; Alter, Svenja; Dresselhaus, Thomas

    2014-01-01

    THE LAUNCH OF SEED DEVELOPMENT IN FLOWERING PLANTS (ANGIOSPERMS) IS INITIATED BY THE PROCESS OF DOUBLE FERTILIZATION: two male gametes (sperm cells) fuse with two female gametes (egg and central cell) to form the precursor cells of the two major seed components, the embryo and endosperm, respectively. The immobile sperm cells are delivered by the pollen tube toward the ovule harboring the female gametophyte by species-specific pollen tube guidance and attraction mechanisms. After pollen tube burst inside the female gametophyte, the two sperm cells fuse with the egg and central cell initiating seed development. The fertilized central cell forms the endosperm while the fertilized egg cell, the zygote, will form the actual embryo and suspensor. The latter structure connects the embryo with the sporophytic maternal tissues of the developing seed. The underlying mechanisms of double fertilization are tightly regulated to ensure delivery of functional sperm cells and the formation of both, a functional zygote and endosperm. In this review we will discuss the current state of knowledge about the processes of directed pollen tube growth and its communication with the synergid cells resulting in pollen tube burst, the interaction of the four gametes leading to cell fusion and finally discuss mechanisms how flowering plants prevent multiple sperm cell entry (polyspermy) to maximize their reproductive success.

  20. Consequences of hyperthyroidism in male and female fertility: pathophysiology and current management.

    Science.gov (United States)

    Mintziori, G; Kita, M; Duntas, L; Goulis, D G

    2016-08-01

    Thyroid hormone acts on the oocytes, sperm and embryo during fertilization, implantation and placentation. Both hypothyroidism and hyperthyroidism may influence fertility. However, evidence of the association of hyperthyroidism with infertility is scarce and sometimes conflicting. Thyroid hormone influences human reproduction via a variety of mechanisms at both the central and the peripheral level. Infertility may occur in hyperthyroid men and women, but it is usually reversible upon restoration of euthyroidism. This review aims to summarize the available data on the association of hyperthyroidism and infertility in both men and women and to provide practical suggestions for the management of these patients.

  1. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Doctor Information for Patients Many adult survivors of childhood cancer feel fertility preservation and the ability to ... after chemotherapy in male and female survivors of childhood cancer treated between 1970 and 1999: a report ...

  2. Genome-wide association mapping for female fertility traits in Danish and Swedish Holstein cattle

    DEFF Research Database (Denmark)

    Sahana, G; Guldbrandtsen, B; Bendixen, C

    2010-01-01

    A genome-wide association study was conducted using a mixed model analysis for QTL for fertility traits in Danish and Swedish Holstein cattle. The analysis incorporated 2,531 progeny tested bulls, and a total of 36 387 SNP markers on 29 bovine autosomes were used. Eleven fertility traits were ana...

  3. No sex in fungus-farming ants or their crops.

    Science.gov (United States)

    Himler, Anna G; Caldera, Eric J; Baer, Boris C; Fernández-Marín, Hermógenes; Mueller, Ulrich G

    2009-07-22

    Asexual reproduction imposes evolutionary handicaps on asexual species, rendering them prone to extinction, because asexual reproduction generates novel genotypes and purges deleterious mutations at lower rates than sexual reproduction. Here, we report the first case of complete asexuality in ants, the fungus-growing ant Mycocepurus smithii, where queens reproduce asexually but workers are sterile, which is doubly enigmatic because the clonal colonies of M. smithii also depend on clonal fungi for food. Degenerate female mating anatomy, extensive field and laboratory surveys, and DNA fingerprinting implicate complete asexuality in this widespread ant species. Maternally inherited bacteria (e.g. Wolbachia, Cardinium) and the fungal cultivars can be ruled out as agents inducing asexuality. M. smithii societies of clonal females provide a unique system to test theories of parent-offspring conflict and reproductive policing in social insects. Asexuality of both ant farmer and fungal crop challenges traditional views proposing that sexual farmer ants outpace coevolving sexual crop pathogens, and thus compensate for vulnerabilities of their asexual crops. Either the double asexuality of both farmer and crop may permit the host to fully exploit advantages of asexuality for unknown reasons or frequent switching between crops (symbiont reassociation) generates novel ant-fungus combinations, which may compensate for any evolutionary handicaps of asexuality in M. smithii.

  4. The Drosophila Su(var)3–7 Gene Is Required for Oogenesis and Female Fertility, Genetically Interacts with piwi and aubergine, but Impacts Only Weakly Transposon Silencing

    Science.gov (United States)

    Begeot, Flora; Koryakov, Dmitry E.; Todeschini, Anne-Laure; Ronsseray, Stéphane; Vieira, Cristina; Spierer, Pierre; Delattre, Marion

    2014-01-01

    Heterochromatin is made of repetitive sequences, mainly transposable elements (TEs), the regulation of which is critical for genome stability. We have analyzed the role of the heterochromatin-associated Su(var)3–7 protein in Drosophila ovaries. We present evidences that Su(var)3–7 is required for correct oogenesis and female fertility. It accumulates in heterochromatic domains of ovarian germline and somatic cells nuclei, where it co-localizes with HP1. Homozygous mutant females display ovaries with frequent degenerating egg-chambers. Absence of Su(var)3–7 in embryos leads to defects in meiosis and first mitotic divisions due to chromatin fragmentation or chromosome loss, showing that Su(var)3–7 is required for genome integrity. Females homozygous for Su(var)3–7 mutations strongly impair repression of P-transposable element induced gonadal dysgenesis but have minor effects on other TEs. Su(var)3–7 mutations reduce piRNA cluster transcription and slightly impact ovarian piRNA production. However, this modest piRNA reduction does not correlate with transposon de-silencing, suggesting that the moderate effect of Su(var)3–7 on some TE repression is not linked to piRNA production. Strikingly, Su(var)3–7 genetically interacts with the piwi and aubergine genes, key components of the piRNA pathway, by strongly impacting female fertility without impairing transposon silencing. These results lead us to propose that the interaction between Su(var)3–7 and piwi or aubergine controls important developmental processes independently of transposon silencing. PMID:24820312

  5. Asexual propagation in the coral reef macroalga Halimeda (Chlorophyta, Bryopsidales) : production, dispersal and attachment of small fragments

    NARCIS (Netherlands)

    Walters, LJ; Coyer, JA; Hunter, CL; Beach, KS; Vroom, PS

    2002-01-01

    Siphonous, green macroalgae of the genus Halimeda are ubiquitous and ecologically important in tropical and subtropical marine environments. It has been hypothesized that the abundance of Halimeda on coral reefs is in part due to the ability of this genus to propagate asexually via vegetative

  6. Comparative Transcriptomic and Proteomic Analyses Reveal a FluG-Mediated Signaling Pathway Relating to Asexual Sporulation of Antrodia camphorata.

    Science.gov (United States)

    Li, Hua-Xiang; Lu, Zhen-Ming; Zhu, Qing; Gong, Jin-Song; Geng, Yan; Shi, Jin-Song; Xu, Zheng-Hong; Ma, Yan-He

    2017-09-01

    Medicinal mushroom Antrodia camphorata sporulate large numbers of arthroconidia in submerged fermentation, which is rarely reported in basidiomycetous fungi. Nevertheless, the molecular mechanisms underlying this asexual sporulation (conidiation) remain unclear. Here, we used comparative transcriptomic and proteomic approaches to elucidate possible signaling pathway relating to the asexual sporulation of A. camphorata. First, 104 differentially expressed proteins and 2586 differential cDNA sequences during the culture process of A. camphorata were identified by 2DE and RNA-seq, respectively. By applying bioinformatics analysis, a total of 67 genes which might play roles in the sporulation were obtained, and 18 of these genes, including fluG, sfgA, SfaD, flbA, flbB, flbC, flbD, nsdD, brlA, abaA, wetA, ganB, fadA, PkaA, veA, velB, vosA, and stuA might be involved in a potential FluG-mediated signaling pathway. Furthermore, the mRNA expression levels of the 18 genes in the proposed FluG-mediated signaling pathway were analyzed by quantitative real-time PCR. In summary, our study helps elucidate the molecular mechanisms underlying the asexual sporulation of A. camphorata, and provides also useful transcripts and proteome for further bioinformatics study of this valuable medicinal mushroom. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Birth Order and Sibling Sex Ratio in a Population with High Fertility: Are Turkish Male to Female Transsexuals Different?

    Science.gov (United States)

    Bozkurt, Ali; Bozkurt, Ozlem Hekim; Sonmez, Ipek

    2015-07-01

    Western studies have consistently found that androphilic (sexually attracted to men) male-to-female transsexuals have a later birth order and a relative excess of brothers compared with appropriate control participants. However, non-Western studies on birth order and sibling sex ratio in androphilic males (transsexual or non-transsexual) are rare. The objective of the study was to test the hypothesis that androphilic male-to-female transsexuals have a late birth order and a relative excess of brothers in a non-Western culture with a higher fertility rate. The participants were 60 androphilic male-to-female transsexuals and 61 male heterosexual controls. The transsexual participants had significantly more older brothers than the control participants, but the groups did not differ in their numbers of older sisters, younger brothers, or younger sisters. The foregoing pattern is usually referred to as the "fraternal birth order effect." Slater's and Berglin's Indexes both showed that the mean birth order of the control participants was very close to that expected from a random sample drawn from a demographically stable population whereas the mean birth order of the transsexual participants was later. A measure of sibship composition, brothers/all siblings, showed that the transsexual group had a higher proportion of male siblings compared with the control group. In conclusion, the present study found that Turkish androphilic male-to-female transsexuals show the same high fraternal birth order that has been found in comparable androphilic samples in Western Europe, North America, and the South Pacific, which suggests a common underlying biological causal mechanism.

  8. A unique mating strategy without physical contact during fertilization in Bombay Night Frogs (Nyctibatrachus humayuni) with the description of a new form of amplexus and female call.

    Science.gov (United States)

    Willaert, Bert; Suyesh, Robin; Garg, Sonali; Giri, Varad B; Bee, Mark A; Biju, S D

    2016-01-01

    Anurans show the highest diversity in reproductive modes of all vertebrate taxa, with a variety of associated breeding behaviours. One striking feature of anuran reproduction is amplexus. During this process, in which the male clasps the female, both individuals' cloacae are juxtaposed to ensure successful external fertilization. Several types of amplexus have evolved with the diversification of anurans, and secondary loss of amplexus has been reported in a few distantly related taxa. Within Nyctibatrachus, a genus endemic to the Western Ghats of India, normal axillary amplexus, a complete loss of amplexus, and intermediate forms of amplexus have all been suggested to occur, but many species remain unstudied. Here, we describe the reproductive behaviour of N. humayuni, including a new type of amplexus. The dorsal straddle, here defined as a loose form of contact in which the male sits on the dorsum of the female prior to oviposition but without clasping her, is previously unreported for anurans. When compared to known amplexus types, it most closely resembles the form of amplexus observed in Mantellinae. Furthermore, we prove that, opposed to the situation in most anurans, male semen release happens before egg deposition. We hypothesize that the male ejaculates on the female's dorsum and that sperm subsequently runs from her back and hind legs before fertilizing the eggs. A second feature characterizing anuran breeding is the advertisement call, mostly produced solely by males. Despite recent descriptions of several new Nyctibatrachus species, few studies have explored their vocal repertoire. We describe both the male advertisement call and a female call for N. humayuni. The presence of a female call has not been reported within Nyctibatrachidae, and has been reported in less than 0.5% of anuran species. Altogether, our results highlight a striking diversity and several unique aspects of Nyctibatrachus breeding behaviour.

  9. Cytogenetical investigations on fertilization, embriogenesis and fruit formation by irradiated pollen. [Gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Dryanovska, O.

    1981-01-01

    The mechanism of fertilization pollination with gamma-irradiated pollen (1-500 kR) in plants of various double fertilization: Crepis (Nicotiana tabacum, Lycopersicum esculentum, Solanum melongena, Ornithogalum gramminifolium, Melandrium rubrum) type, Lilium (Lilium speciosum) type, and Trandescantia (Tradescantia paludosa) type was studied, along with the opportunity of its modification, embryogenesis and fruit and seed formation. In the Crepis type, depending on the disturbances of male chromatin, fertilization manifested itself as: 1) normal karyogamy with decondensation of male chromatin and the formation of supplementary nucleoli and further development of embryo and endosperm (1-500 kR); 2) karyogamy without decondensation and functioning of the male chromatin (1-500 kR); 3) karyogamy or sticking the male chromatin to the nuclei of the female sex cells, stimulating the development of the ovule, embryo, and endosperm (50-500 kR); 4) sticking the highly pycnotized male chromatin to the nuclei of the female sex cells without evidence of zygote and endosperm function and further development (50-500 kR). In the Lilium type modification of fertilization was manifested by: 1) normal karyogamy with developing diploid embryos and pentaploid endosperm with aberrations (1-20 kK); 2) sticking the male chromatin to the nuclei of the female sex cells and stimulation of their development (50-500 kR). In the Trandescantia type the irradiated male chromatin modified fertilization as: 1) karyogamy with spermia having fragments, two spermia connected by a bridge or with a generative nucleus with aberrations (1-50 kR); 2) karyogamy without developing the female sex nuclei (10-500kR); 3) karyogamy or sticking the male chromatin to the female sex cell nuclei and stimulation of their development (10-500 kR); 4) sticking the male chromatin with no stimulating effect (10-500 kR).

  10. The Trade-Off between Female Fertility and Longevity during the Epidemiological Transition in the Netherlands

    DEFF Research Database (Denmark)

    Kaptijn, Ralf; Thomese, Fleur; Liefbroer, Aart C

    2015-01-01

    as an evolutionary trade-off between reproduction and survival. We examine the relationship between fertility and longevity during the epidemiological transition in the Netherlands. This period of rapid decline in mortality from infectious diseases offers a good opportunity to study the relationship between...... fertility and longevity, using registry data from 6,359 women born in The Netherlands between 1850 and 1910. We hypothesize that an initially negative relationship between women's fertility and their longevity gradually turns less negative during the epidemiological transition, because of decreasing costs...

  11. Protein Kinase A subunits of the ascomycete pathogen Mycosphaerella graminicola regulate asexual fructification, filamentation, melanization and osmosensing

    NARCIS (Netherlands)

    Mehrabi, R.; Kema, G.H.J.

    2006-01-01

    As in many fungi, asexual reproduction of Mycosphaerella graminicola in planta is a complex process that requires proper differentiation of the infectious hyphae in the substomatal cavities of foliar tissue before pycnidia with conidia can be formed. In this study, we have investigated the role of

  12. Lepidium meyenii (Maca increases litter size in normal adult female mice

    Directory of Open Access Journals (Sweden)

    Gasco Manuel

    2005-05-01

    Full Text Available Abstract Background Lepidium meyenii, known as Maca, grows exclusively in the Peruvian Andes over 4000 m altitude. It has been used traditionally to increase fertility. Previous scientific studies have demonstrated that Maca increases spermatogenesis and epididymal sperm count. The present study was aimed to investigate the effects of Maca on several fertility parameters of female mice at reproductive age. Methods Adult female Balb/C mice were divided at random into three main groups: i Reproductive indexes group, ii Implantation sites group and iii Assessment of uterine weight in ovariectomized mice. Animals received an aqueous extract of lyophilized Yellow Maca (1 g/Kg BW or vehicle orally as treatment. In the fertility indexes study, animals received the treatment before, during and after gestation. The fertility index, gestation index, post-natal viability index, weaning viability index and sex ratio were calculated. Sexual maturation was evaluated in the female pups by the vaginal opening (VO day. In the implantation study, females were checked for implantation sites at gestation day 7 and the embryos were counted. In ovariectomized mice, the uterine weight was recorded at the end of treatment. Results Implantation sites were similar in mice treated with Maca and in controls. All reproductive indexes were similar in both groups of treatment. The number of pups per dam at birth and at postnatal day 4 was significantly higher in the group treated with Maca. VO day occurred earlier as litter size was smaller. Maca did not affect VO day. In ovariectomized mice, the treatment with Maca increased significantly the uterine weights in comparison to their respective control group. Conclusion Administration of aqueous extract of Yellow Maca to adult female mice increases the litter size. Moreover, this treatment increases the uterine weight in ovariectomized animals. Our study confirms for the first time some of the traditional uses of Maca to

  13. Sperm swimming velocity predicts competitive fertilization success in the green swordtail Xiphophorus helleri.

    Directory of Open Access Journals (Sweden)

    Clelia Gasparini

    Full Text Available Sperm competition is expected to favour the evolution of traits that influence the performance of sperm when they compete to fertilize a female's eggs. While there is considerable evidence that selection favours increases in sperm numbers, much less is known about how sperm quality contributes towards competitive fertilization success. Here, we determine whether variation in sperm quality influences competitive fertilization success in the green swordtail Xiphophorus helleri, a highly promiscuous livebearing fish. We use artificial insemination as a method of controlled sperm delivery and show that sperm swimming velocity is the primary determinant of fertilization success when ejaculates from two males compete to fertilize a female's eggs. By contrast, we found no evidence that sperm length had any effect on siring success. We also found no evidence that pre- and postcopulatory sexual traits were phenotypically integrated in this species, suggesting that the previous observation that reproductive skew favours males with high mating rates is unlikely to be due to any direct association between sperm quality and male sexual ornamentation.

  14. Too old to have children? Lessons from natural fertility populations.

    Science.gov (United States)

    Eijkemans, Marinus J C; van Poppel, Frans; Habbema, Dik F; Smith, Ken R; Leridon, Henri; te Velde, Egbert R

    2014-06-01

    Is it possible to construct an age curve denoting the ages above which women are biologically too old to reproduce? We constructed a curve based on the distribution of female age at last birth in natural fertility populations reflecting the ages above which women have become biologically too old to have children. The median age at last birth (ALB) for females is ∼40-41 years of age across a range of natural fertility populations. This suggests that there is a fairly universal pattern of age-related fertility decline. However, little is known about the distribution of female ALB and in the present era of modern birth control, it is impossible to assess the age-specific distribution of ALB. Reliable information is lacking that could benefit couples who envisage delaying childbearing. This study is a review of high-quality historical data sets of natural fertility populations in which the distributions of female age at last birth were analysed. The studies selected used a retrospective cohort design where women were followed as they age through their reproductive years. Using a common set of eligibility criteria, large data files of natural fertility populations were prepared such that the analysis could be performed in parallel across all populations. Data on the ALB and confounding variables are presented as box and whisker plots denoting the 5th, 25th, 50th, 75th and 95th percentile distribution of the age at last birth for each population. The analysis includes the estimation of Kaplan-Meier curves for age at last birth of each population. The hazard curve for ALB was obtained by plotting the smoothed hazard curve of each population and taking the lowest hazard within a time period of at least 5 years. This lowest hazard curve was then transformed into a cumulative distribution function representing the composite curve of the end of biological fertility. This curve was based on the data from three of the six populations, having the lowest hazards of end of

  15. An empirical investigation of female labor-force participation, fertility, age at marriage, and wages in Korea.

    Science.gov (United States)

    Lee, B S; Mcelwain, A M

    1985-07-01

    The Korean experience raises questions about the assumption that successful economic development and equitable income distribution are preconditions for rapid fertility declines. During the 1960-70 decade, the total fertility rate in Korea declined by 36% and the crude birth rate fell by 33%, in the absence of significant economic development. This paper uses data from the 1974 Korean Fertility Survey to explore the relationships between the factors responsible for this rapid fertility decline. A simultaneous equation model of fertility, age at marriage, extent of labor force participation during marriage, quality of children, and wages is developed and tested. Rather than to provide definitive measures of these interrelationships, the aim was to investigate the utility of treating several variables as being jointly determined. The results suggest that parental education affects fertility by influencing age at marriage, implying that adult education programs will have little effect on marital fertility. There was some evidence that working women whose jobs are compatible with child care have more children than nonworking women, a finding that should be considered in planning increased job opportunities for women. Urbanized women and those who work before marriage tend to marry later than their less urbanized counterparts or women who do not work prior to marriage. Finally, women who used modern methods of birth control had significantly lower fertility than nonusers of modern methods. There is concern that the Government has reduced budgetary appropriations to family planning since the goal of reducing the annual population growth rate from 3% in 1960 to 2% in 1970 was achieved. It is suggested that family planning expenditures should be deployed to areas such as urban slums that have not yet been reached by family planning programs.

  16. Male irradiation affects female remating behavior in Anastrepha serpentina (Diptera: Tephritidae).

    Science.gov (United States)

    Landeta-Escamilla, Anais; Hernández, Emilio; Arredondo, José; Díaz-Fleischer, Francisco; Pérez-Staples, Diana

    2016-02-01

    Female remating in target pest species can affect the efficacy of control methods such as the Sterile Insect Technique (SIT) but very little is known about the postcopulatory mating behavior of these pests. In this study, we investigated the remating behavior of female Anastrepha serpentina (Diptera: Tephritidae), an oligophagous pest of Sapotaceae. First, we tested how long the sexual refractory period of females lasted after an initial mating. Second, we tested the effect of male and female sterility, female ovipositing opportunities and male density on female propensity to remate. Lastly, we tested if the amount of sperm stored by females was correlated to the likelihood of females to remate. We found that receptivity of mass-reared A. serpentina females had a bimodal response, with up to 16% of mass-reared A. serpentina females remating five days after the initial copulation, decreasing to 2% at 10 and 15 days and increasing to 13% after 20 days. Compared to fertile males, sterile males were less likely to mate and less likely to inhibit females from remating. Copula duration of sterile males was shorter compared to fertile males. Remating females were less likely to mate with a sterile male as a second mate. Sterile females were less likely to mate or remate compared to fertile females. Opportunity to oviposit and male density had no effect on female remating probability. Sperm numbers were not correlated with female likelihood to remate. Information on the post-copulatory behavior of mass-reared A. serpentina will aid fruit fly managers in improving the quality of sterile males. We discuss our results in terms of the differences this species presents in female remating behavior compared to other tephritids. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Reduced costs of reproduction in females mediate a shift from a male-biased to a female-biased lifespan in humans

    Science.gov (United States)

    Bolund, Elisabeth; Lummaa, Virpi; Smith, Ken R.; Hanson, Heidi A.; Maklakov, Alexei A.

    2016-01-01

    The causes underlying sex differences in lifespan are strongly debated. While females commonly outlive males in humans, this is generally less pronounced in societies before the demographic transition to low mortality and fertility rates. Life-history theory suggests that reduced reproduction should benefit female lifespan when females pay higher costs of reproduction than males. Using unique longitudinal demographic records on 140,600 reproducing individuals from the Utah Population Database, we demonstrate a shift from male-biased to female-biased adult lifespans in individuals born before versus during the demographic transition. Only women paid a cost of reproduction in terms of shortened post-reproductive lifespan at high parities. Therefore, as fertility decreased over time, female lifespan increased, while male lifespan remained largely stable, supporting the theory that differential costs of reproduction in the two sexes result in the shifting patterns of sex differences in lifespan across human populations. Further, our results have important implications for demographic forecasts in human populations and advance our understanding of lifespan evolution. PMID:27087670

  18. Profiles of fertility, labour supply and wages of married women: a complete life-cycle model.

    Science.gov (United States)

    Moffitt, R

    1984-01-01

    Trends in fertility and female labor supply have changed dramatically since World War II. Fertility rates rose steadily from the 1940's until the early 1960's and thereafter declined, while female laborforce participation rates have continually grown since the 1950's. These 2 rates are closely linked. Labor supply and fertility decisions are also life-cycle decisions. In addition, wage and job prospects are related to job choice and in turn to fertility decisions. Labor supply, fertility, and wages are linked in an econometric model which takes into account the problems of heterogeneity of tastes, the problem of missing wage rates through nonworking, and the problem of simultaneous-equations bias. Past works are critiqued, mainly on the basis that few analyses recognize the interrelatedness of fertility and labor supply in any sense--static or dynamic. Nor do most researchers consider age-specific fertility equations in analyzing female labor supply. Moffitt's model is a beginning analysis of fertility and labor supply as a joint consumer-demand choice. Patterns of a couple's future consumption, wife's labor supply, and births are assumed to be planned at the beginning of marriage. These patterns depend on the constraints of budget, fertility, and of inverse production (the differing amounts of time it takes to care for a child as the child matures) as well as wage accumulation. Exogenous wealth and beginning wages are considered as well. This model does not account for a woman's work experience prior to marriage. According to the model, fertility rates rise in the 1st year of marriage and subsequently fall off. Employment rates drop off at an accelerating rate until the 6th year of marriage and then increase. A rise in wage level decreases the probability of birth and increases the probability ow working. Also, changes in fertility rates have more to do with wage changes than with a woman's cohort.

  19. Female self-employment and children

    NARCIS (Netherlands)

    Noseleit, Florian

    2014-01-01

    Several analyses report a positive correlation between fertility and female self-employment; however, scholars disagree about the direction of this relationship. Knowing about the causal relationship is important because the relevant mechanisms and possible implications differ tremendously. This

  20. A population-based survey on family intentions and fertility awareness in women and men in the United Kingdom and Denmark

    DEFF Research Database (Denmark)

    Vassard, Ditte; Lallemant, Camille; Nyboe Andersen, Anders

    2016-01-01

    BACKGROUND: Across several European countries family formation is increasingly postponed. The aims of the study were to investigate the desire for family building and fertility awareness in the UK and Denmark. METHODS: A population-based internet survey was used among women (n = 1,000) and men (n...... starts to decline around 25-30 years. Men had significantly lower fertility awareness. Women who underestimated the impact of age on female fertility were significantly more likely to have a desire or attempted their first child at a higher age. CONCLUSION: Even though the majority were aware of the age......-related decrease in female fertility, most desired having children at an age when female fertility has declined. Women who were not sufficiently aware of the impact of advanced age were significantly more likely to have their first child at a higher age. There is a need for developing educational programs...

  1. Evolutionary restoration of fertility in an interspecies hybrid yeast, by whole-genome duplication after a failed mating-type switch.

    Directory of Open Access Journals (Sweden)

    Raúl A Ortiz-Merino

    2017-05-01

    Full Text Available Many interspecies hybrids have been discovered in yeasts, but most of these hybrids are asexual and can replicate only mitotically. Whole-genome duplication has been proposed as a mechanism by which interspecies hybrids can regain fertility, restoring their ability to perform meiosis and sporulate. Here, we show that this process occurred naturally during the evolution of Zygosaccharomyces parabailii, an interspecies hybrid that was formed by mating between 2 parents that differed by 7% in genome sequence and by many interchromosomal rearrangements. Surprisingly, Z. parabailii has a full sexual cycle and is genetically haploid. It goes through mating-type switching and autodiploidization, followed by immediate sporulation. We identified the key evolutionary event that enabled Z. parabailii to regain fertility, which was breakage of 1 of the 2 homeologous copies of the mating-type (MAT locus in the hybrid, resulting in a chromosomal rearrangement and irreparable damage to 1 MAT locus. This rearrangement was caused by HO endonuclease, which normally functions in mating-type switching. With 1 copy of MAT inactivated, the interspecies hybrid now behaves as a haploid. Our results provide the first demonstration that MAT locus damage is a naturally occurring evolutionary mechanism for whole-genome duplication and restoration of fertility to interspecies hybrids. The events that occurred in Z. parabailii strongly resemble those postulated to have caused ancient whole-genome duplication in an ancestor of Saccharomyces cerevisiae.

  2. Mature Oocyte Cryopreservation for Fertility Preservation.

    Science.gov (United States)

    Liang, Tina; Motan, Tarek

    2016-01-01

    In recent decades, advances in cancer treatment have led to a dramatic improvement in long term survival. This has led to an increasing focus on quality of life after surviving cancer treatment, with fertility being an important aspect. Given the known reproductive risks of cancer therapies, there has been a growing interest in the field of fertility preservation (also referred to as oncofertility). Mature oocyte cryopreservation is no longer considered experimental and has become a realistic option for reproductive aged women prior to undergoing cancer treatment. Additionally, as cryopreservation techniques improve, mature oocyte cryopreservation is increasing being marketed to healthy women without cancer wishing to delay child bearing, also termed "social egg freezing". This chapter provides a review of the current technology, use, and outcomes of mature oocyte cryopreservation. It also outlines the ethical debate surrounding social egg freezing and directions for future research in female fertility preservation.

  3. Female in-nest chatter song increases predation

    OpenAIRE

    Kleindorfer, Sonia; Evans, Christine; Mahr, Katharina

    2016-01-01

    Female song is an ancestral trait in songbirds, yet extant females generally sing less than males. Here, we examine sex differences in the predation cost of singing behaviour. The superb fairy-wren (Malurus cyaneus) is a Southern Hemisphere songbird; males and females provision the brood and produce solo song year-round. Both sexes had higher song rate during the fertile period and lower song rate during incubation and chick feeding. Females were more likely than males to sing close to or ins...

  4. Fertility behavior in rural and urban Indonesia.

    Science.gov (United States)

    Chernichovsky, D; Newlon, B; Sigit, H

    1982-06-01

    The cross-sectional picture of urban and rural fertility which emerges from recently published Indonesian national level data from the 1976 Intercensal Survey are described. The data reveal only small differences in the average numbers of children ever born or children surviving of ever married women (or mothers) in urban and rural areas of Indonesia. In urban areas, ever married mothers had a standardized average of 3.4 children ever born, and in rural areas 3.3 These averages cannot reveal any differences in past and present childbearing levels. The fertility of urban women, as opposed to rural women, appeared more highly associated with indicators which tend to directly or indirectly depress the average number of children ever born: a higher age at 1st marriage; a higher level of "sterility;" a higher survival ratio of children born; and a higher level of educational attainment. At least some of these factors might be regarded as associated with modernizing trends in the urban areas: increased accessibility to educational facilities; the opening of female opportunities outside the home so that marriage occurs later in life; and a better health environment so that there is less pregnancy wastage and time spent in bearing children. These factors help to provide an incentive to women to limit their fertility; knowledge of contraception methods provides a means. The depressing factors most highly associated with average rural fertility do not appear associated with modernization but with traditional folk customs regarding acceptable behavior. The inflating effects of early marriage are offset by a greater prevalence of marital disruption. This may reflect a cultural acceptability. The reasons may include adolescent or true sterility leading to disunion, the outmigration of a partner, or some other form of disharmony. Female labor force participation is more prevalent in rural than urban areas. There are both traditional and modern aspects to be seen in its

  5. The Deep Correlation between Energy Metabolism and Reproduction: A View on the Effects of Nutrition for Women Fertility.

    Science.gov (United States)

    Fontana, Roberta; Della Torre, Sara

    2016-02-11

    In female mammals, mechanisms have been developed, throughout evolution, to integrate environmental, nutritional and hormonal cues in order to guarantee reproduction in favorable energetic conditions and to inhibit it in case of food scarcity. This metabolic strategy could be an advantage in nutritionally poor environments, but nowadays is affecting women's health. The unlimited availability of nutrients, in association with reduced energy expenditure, leads to alterations in many metabolic pathways and to impairments in the finely tuned inter-relation between energy metabolism and reproduction, thereby affecting female fertility. Many energetic states could influence female reproductive health being under- and over-weight, obesity and strenuous physical activity are all conditions that alter the profiles of specific hormones, such as insulin and adipokines, thus impairing women fertility. Furthermore, specific classes of nutrients might affect female fertility by acting on particular signaling pathways. Dietary fatty acids, carbohydrates, proteins and food-associated components (such as endocrine disruptors) have per se physiological activities and their unbalanced intake, both in quantitative and qualitative terms, might impair metabolic homeostasis and fertility in premenopausal women. Even though we are far from identifying a "fertility diet", lifestyle and dietary interventions might represent a promising and invaluable strategy to manage infertility in premenopausal women.

  6. The Deep Correlation between Energy Metabolism and Reproduction: A View on the Effects of Nutrition for Women Fertility

    Directory of Open Access Journals (Sweden)

    Roberta Fontana

    2016-02-01

    Full Text Available In female mammals, mechanisms have been developed, throughout evolution, to integrate environmental, nutritional and hormonal cues in order to guarantee reproduction in favorable energetic conditions and to inhibit it in case of food scarcity. This metabolic strategy could be an advantage in nutritionally poor environments, but nowadays is affecting women’s health. The unlimited availability of nutrients, in association with reduced energy expenditure, leads to alterations in many metabolic pathways and to impairments in the finely tuned inter-relation between energy metabolism and reproduction, thereby affecting female fertility. Many energetic states could influence female reproductive health being under- and over-weight, obesity and strenuous physical activity are all conditions that alter the profiles of specific hormones, such as insulin and adipokines, thus impairing women fertility. Furthermore, specific classes of nutrients might affect female fertility by acting on particular signaling pathways. Dietary fatty acids, carbohydrates, proteins and food-associated components (such as endocrine disruptors have per se physiological activities and their unbalanced intake, both in quantitative and qualitative terms, might impair metabolic homeostasis and fertility in premenopausal women. Even though we are far from identifying a “fertility diet”, lifestyle and dietary interventions might represent a promising and invaluable strategy to manage infertility in premenopausal women.

  7. A combined approach to heat stress effect on male fertility in Nasonia vitripennis: from the physiological consequences on spermatogenesis to the reproductive adjustment of females mated with stressed males.

    Directory of Open Access Journals (Sweden)

    Marlène Chirault

    Full Text Available In recent years, several studies have shown a decline in reproductive success in males in both humans and wildlife. Research on male fertility has largely focused on vertebrates, although invertebrates constitute the vast majority of terrestrial biodiversity. The reduction of their reproductive capacities due to environmental stresses can have strong negative ecological impacts, and also dramatic consequences on world food production if it affects the reproductive success of biological control agents, such as parasitic wasps used to control crop pests. Here Nasonia vitripennis, a parasitic wasp of various fly species, was studied to test the effects of 24h-heat stress applied during the first pupal stage on male fertility. Results showed that only primary spermatocytes were present at the first pupal stage in all cysts of the testes. Heat stress caused a delay in spermatogenesis during development and a significant decrease in sperm stock at emergence. Females mated with these heat-stressed males showed a reduce sperm count stored in their spermatheca. Females did not appear to distinguish heat-stressed from control males and did not remate more frequently to compensate for the lack of sperm transferred. As a result, females mated with heat-stressed males produced a suboptimal lifetime offspring sex ratio compared to those mated with control males. This could further impact the population dynamics of this species. N. vitripennis appears to be an interesting biological model to study the mechanisms of subfertility and its consequence on female reproductive strategies and provides new research perspectives in both invertebrates and vertebrates.

  8. A combined approach to heat stress effect on male fertility in Nasonia vitripennis: from the physiological consequences on spermatogenesis to the reproductive adjustment of females mated with stressed males.

    Science.gov (United States)

    Chirault, Marlène; Lucas, Christophe; Goubault, Marlène; Chevrier, Claude; Bressac, Christophe; Lécureuil, Charlotte

    2015-01-01

    In recent years, several studies have shown a decline in reproductive success in males in both humans and wildlife. Research on male fertility has largely focused on vertebrates, although invertebrates constitute the vast majority of terrestrial biodiversity. The reduction of their reproductive capacities due to environmental stresses can have strong negative ecological impacts, and also dramatic consequences on world food production if it affects the reproductive success of biological control agents, such as parasitic wasps used to control crop pests. Here Nasonia vitripennis, a parasitic wasp of various fly species, was studied to test the effects of 24h-heat stress applied during the first pupal stage on male fertility. Results showed that only primary spermatocytes were present at the first pupal stage in all cysts of the testes. Heat stress caused a delay in spermatogenesis during development and a significant decrease in sperm stock at emergence. Females mated with these heat-stressed males showed a reduce sperm count stored in their spermatheca. Females did not appear to distinguish heat-stressed from control males and did not remate more frequently to compensate for the lack of sperm transferred. As a result, females mated with heat-stressed males produced a suboptimal lifetime offspring sex ratio compared to those mated with control males. This could further impact the population dynamics of this species. N. vitripennis appears to be an interesting biological model to study the mechanisms of subfertility and its consequence on female reproductive strategies and provides new research perspectives in both invertebrates and vertebrates.

  9. MicroRNAs: From Female Fertility, Germ Cells, and Stem Cells to Cancer in Humans

    Directory of Open Access Journals (Sweden)

    Irma Virant-Klun

    2016-01-01

    Full Text Available MicroRNAs are a family of naturally occurring small noncoding RNA molecules that play an important regulatory role in gene expression. They are suggested to regulate a large proportion of protein encoding genes by mediating the translational suppression and posttranscriptional control of gene expression. Recent findings show that microRNAs are emerging as important regulators of cellular differentiation and dedifferentiation, and are deeply involved in developmental processes including human preimplantation development. They keep a balance between pluripotency and differentiation in the embryo and embryonic stem cells. Moreover, it became evident that dysregulation of microRNA expression may play a fundamental role in progression and dissemination of different cancers including ovarian cancer. The interest is still increased by the discovery of exosomes, that is, cell-derived vesicles, which can carry different proteins but also microRNAs between different cells and are involved in cell-to-cell communication. MicroRNAs, together with exosomes, have a great potential to be used for prognosis, therapy, and biomarkers of different diseases including infertility. The aim of this review paper is to summarize the existent knowledge on microRNAs related to female fertility and cancer: from primordial germ cells and ovarian function, germinal stem cells, oocytes, and embryos to embryonic stem cells.

  10. Fertility desires and fertility outcomes.

    Science.gov (United States)

    Bracher, M; Santow, G

    1991-05-01

    An Australian 1-in-1000 national probability sample conducted in 1986 yielded 2547 women aged 20-59 who provided detailed life histories on marital unions, childbearing, and contraception. Age specific fertility rates, desired family size, differentials in desired family size, desired fertility and achieved fertility, and sequential family building are examined. The results indicate that the desired family size at 1st marriage has declined only slightly over the past 30 years. 3 children are generally desired, and ver few desire 2. The constance of fertility desires in contrasted with the fertilitydecline to below replacement levels. Several reasons are suggested for the desired family size: the desire is for a family size within the family tradition and modified by the desire to have 1 of each sex, the desire reflects less on intentions but more on normative pressure to become a parent. Marrying is self selecting on the desire for a traditional family of at least 2 children. There is a rising age at marriage as well as a decline in marriages. Desired family size exceeds completed fertility. Period factors and personal circumstances affect fertility intentions. Future inquires should explore the multiple factors relating to fertility, rather than in comparing fertility desires and actual fertility. The data collected on age specific fertility were comparable to official estimates. The fertility decline was evidenced in all groups except teenagers. The decline was nearly 50% for those 20-24 years between the 1050's-80's, 33% for ages 25-29. Marriage patterns explain this decline in part. Between 1971-76, women aged 20-25 were married 37 months out of 60 months in 1971-76 versus 25 out of 60 months in 1981-86. Within the 25 year age group, marital fertility has declined and unmarried fertility, which is low, has risen, Women in a marital union of any kind has remained stable. Fertility within de facto unions, which is lower than within marriage, is higher than

  11. Impact of migration on fertility in sub-Saharan Africa.

    Science.gov (United States)

    Brockerhoff, M; Yang, X

    1994-01-01

    Much lower levels of fertility in urban than rural areas throughout sub-Saharan Africa imply that fertility decline in the region may be facilitated by rapid urbanization and rural-to-urban migration. The present study uses data from Demographic and Health Surveys in six countries--Ghana, Kenya, Mali, Senegal, Togo and Uganda--to assess the impact of long-term rural-urban female migration on fertility. Results of logit analyses indicate that in most countries women who leave the countryside represent the higher fertility segment of the rural population in the years before migration. Migrants' risk of conception declines dramatically in all countries around the time of migration and remains lower in the long run among most migrant groups than among rural and urban nonmigrants. Descriptive analyses suggest that the decline in migrant fertility is related to the rapid and pronounced improvement in standard of living experienced by migrants after settling in the urban area and may be due in part to temporary spousal separation.

  12. Chromosome length scaling in haploid, asexual reproduction

    International Nuclear Information System (INIS)

    Oliveira, P M C de

    2007-01-01

    We study the genetic behaviour of a population formed by haploid individuals which reproduce asexually. The genetic information for each individual is stored along a bit-string (or chromosome) with L bits, where 0-bits represent the wild allele and 1-bits correspond to harmful mutations. Each newborn inherits this chromosome from its parent with a few random mutations: on average a fixed number m of bits are flipped. Selection is implemented according to the number N of 1-bits counted along the individual's chromosome: the smaller N the higher the probability an individual has to survive a new time step. Such a population evolves, with births and deaths, and its genetic distribution becomes stabilized after sufficiently many generations have passed. The question we pose concerns the procedure of increasing L. The aim is to get the same distribution of genetic loads N/L among the equilibrated population, in spite of a larger L. Should we keep the same mutation rate m/L for different values of L? The answer is yes, which intuitively seems to be plausible. However, this conclusion is not trivial, according to our simulation results: the question also involves the population size

  13. Fertility and Public Policies - Evidence from Norway and Finland

    Directory of Open Access Journals (Sweden)

    2004-05-01

    Full Text Available The relatively high and rising fertility rates of Nordic countries in the late 1980s and early 1990s sparked a renewed research interest in the possible pronatalistic effects of generous family policy programs. Several studies have addressed this issue, but few have tried to model policy effects explicitly. The existing evidence so far is mainly from Sweden, where policy indicators have been incorporated in economic fertility models that also control for female wages. This paper complements previous Swedish analyses with evidence from Norway and Finland. The results corroborate earlier findings of a negative effect of female wages. There are also indications of a positive policy impact, as maternity leave extensions are estimated to raise birth rates, although mainly higher parity births and mainly in Finland.

  14. Virus epidemics can lead to a population-wide spread of intragenomic parasites in a previously parasite-free asexual population.

    Science.gov (United States)

    Jalasvuori, Matti; Lehtonen, Jussi

    2014-03-01

    Sexual reproduction is problematic to explain due to its costs, most notably the twofold cost of sex. Yet, sex has been suggested to be favourable in the presence of proliferating intragenomic parasites given that sexual recombination provides a mechanism to confine the accumulation of deleterious mutations. Kraaijeveld et al. compared recently the accumulation of transposons in sexually and asexually reproducing lines of the same species, the parasitoid wasp Leptopilina clavipes. They discovered that within asexually reproducing wasps, the number of gypsy-like retrotransposons was increased fourfold, whereas other retrotransposons were not. Interestingly, gypsy-like retrotransposons are closely related to retroviruses. Endogenous retroviruses are retroviruses that have integrated to the germ line cells and are inherited thereafter vertically. They can also replicate within the genome similarly to retrotransposons as well as form virus particles and infect previously uninfected cells. This highlights the possibility that endogenous retroviruses could play a role in the evolution of sexual reproduction. Here, we show with an individual-based computational model that a virus epidemic within a previously parasite-free asexual population may establish a new intragenomic parasite to the population. Moreover and in contrast to other transposons, the possibility of endogenous viruses to maintain a virus epidemic and simultaneously provide resistance to individuals carrying active endogenous viruses selects for the presence of active intragenomic parasites in the population despite their deleterious effects. Our results suggest that the viral nature of certain intragenomic parasites should be taken into account when sex and its benefits are being considered. © 2014 John Wiley & Sons Ltd.

  15. Effect of war on fertility: a review of the literature.

    Science.gov (United States)

    Abu-Musa, Antoine A; Kobeissi, Loulou; Hannoun, Antoine B; Inhorn, Marcia C

    2008-01-01

    The aim of this study was to review the existing literature on the effect of war on female and male fertility. A MEDLINE search for studies that included participants defined as infertile because they were unsuccessful in achieving a pregnancy after a year and studies that assessed the effect of war on semen parameters and menstrual dysfunction were performed. Twenty articles were included in this review. For female fertility, studies showed that women who were prisoners of war or who were living in areas exposed to bombardment had increased risk of menstrual abnormalities. For male fertility, the results were conflicting. The Vietnam War was not associated with difficulty in conception although one study revealed a decrease in sperm characteristics. Studies of male US and Danish 1990/91 Gulf war veterans showed no evidence of reduced fertility; however, studies of UK and Australian veterans reported increased risk of infertility. The Lebanese and Slovenian civil wars were associated with a decrease in sperm parameters. Exposure to mustard gas was also associated with abnormal semen parameters; however, exposure to depleted uranium had no effect on semen characteristics. Most of the studies examined had major limitations including recall bias and small number of cases included.

  16. Behavioural ecology: transient sexual mimicry leads to fertilization.

    Science.gov (United States)

    Hanlon, Roger T; Naud, Marié-Jose; Shaw, Paul W; Havenhand, Jon N

    2005-01-20

    Sexual mimicry among animals is widespread, but does it impart a fertilization advantage in the widely accepted 'sneak-guard' model of sperm competition? Here we describe field results in which a dramatic facultative switch in sexual phenotype by sneaker-male cuttlefish leads to immediate fertilization success, even in the presence of the consort male. These results are surprising, given the high rate at which females reject copulation attempts by males, the strong mate-guarding behaviour of consort males, and the high level of sperm competition in this complex mating system.

  17. Discovery of human posterior head 20 (hPH20) and homo sapiens sperm acrosome associated 1 (hSPACA1) immunocontraceptive epitopes and their effects on fertility in male and female mice.

    Science.gov (United States)

    Chen, Xuemei; Liu, Xiaodong; Ren, Xiuhua; Li, Xuewu; Wang, Li; Zang, Weidong

    2016-03-01

    The key goals of immunocontraception research are to obtain full contraceptive effects using vaccines administered to both males and females. Current research concerning human anti-sperm contraceptive vaccines is focused on delineating infertility-related epitopes to avoid autoimmune disease. We constructed phage-display peptide libraries to select epitope peptides derived from human posterior head 20 (hPH20) and homo sapiens sperm acrosome associated 1 (hSPACA1) using sera collected from infertile women harbouring anti-sperm antibodies. Following five rounds of selection, positive colonies were reconfirmed for reactivity with the immunoinfertile sera. We biopanned and analysed the chemical properties of four epitope peptides, named P82, Sa6, Sa37 and Sa76. Synthetic peptides were made and coupled to either bovine serum albumin (BSA) or ovalbumin. We used the BSA-conjugated peptides to immunise BALB/c mice and examined the effects on fertility in female and male mice. The synthetic peptides generated a sperm-specific antibody response in female and male mice that caused a contraceptive state. The immunocontraceptive effect was reversible and, with the disappearance of peptide-specific antibodies, there was complete restoration of fertility. Vaccinations using P82, Sa6 and Sa76 peptides resulted in no apparent side effects. Thus, it is efficient and practical to identify epitope peptide candidates by phage display. These peptides may find clinical application in the specific diagnosis and treatment of male and female infertility and contraceptive vaccine development.

  18. Sperm should evolve to make female meiosis fair.

    Science.gov (United States)

    Brandvain, Yaniv; Coop, Graham

    2015-04-01

    Genomic conflicts arise when an allele gains an evolutionary advantage at a cost to organismal fitness. Oögenesis is inherently susceptible to such conflicts because alleles compete for inclusion into the egg. Alleles that distort meiosis in their favor (i.e., meiotic drivers) often decrease organismal fitness, and therefore indirectly favor the evolution of mechanisms to suppress meiotic drive. In this light, many facets of oögenesis and gametogenesis have been interpreted as mechanisms of protection against genomic outlaws. That females of many animal species do not complete meiosis until after fertilization, appears to run counter to this interpretation, because this delay provides an opportunity for sperm-acting alleles to meddle with the outcome of female meiosis and help like alleles drive in heterozygous females. Contrary to this perceived danger, the population genetic theory presented herein suggests that, in fact, sperm nearly always evolve to increase the fairness of female meiosis in the face of genomic conflicts. These results are consistent with the apparent sperm dependence of the best characterized female meiotic driversin animals. Rather than providing an opportunity for sperm collaboration in female meiotic drive, the "fertilization requirement" indirectly protects females from meiotic drivers by providing sperm an opportunity to suppress drive. © 2015 The Author(s).

  19. Sperm should evolve to make female meiosis fair

    Science.gov (United States)

    Brandvain, Yaniv; Coop, Graham

    2017-01-01

    Genomic conflicts arise when an allele gains an evolutionary advantage at a cost to organismal fitness. Oögenesis is inherently susceptible to such conflicts because alleles compete for inclusion into the egg. Alleles that distort meiosis in their favor (i.e. meiotic drivers) often decrease organismal fitness, and therefore indirectly favor the evolution of mechanisms to suppress meiotic drive. In this light, many facets of oögenesis and gametogenesis have been interpreted as mechanisms of protection against genomic outlaws. That females of many animal species do not complete meiosis until after fertilization, appears to run counter to this interpretation, because this delay provides an opportunity for sperm-acting alleles to meddle with the outcome of female meiosis and help like alleles drive in heterozygous females. Contrary to this perceived danger, the population genetic theory presented herein suggests that, in fact, sperm nearly always evolve to increase the fairness of female meiosis in the face of genomic conflicts. These results are consistent with the apparent sperm dependence of the best characterized female meiotic drivers in animals. Rather than providing an opportunity for sperm collaboration in female meiotic drive, the ‘fertilization requirement’ indirectly protects females from meiotic drivers by providing sperm an opportunity to suppress drive. PMID:25662355

  20. Cryopreservation of ovarian tissue for fertility preservation in young female oncological patients.

    Science.gov (United States)

    Andersen, Claus Yding; Kristensen, Stine Gry; Greve, Tine; Schmidt, Kirsten Tryde

    2012-05-01

    Girls and women suffering from a cancer that requires treatment with gonadotoxic drugs may experience cessation of reproductive function as a side effect due to obliteration of the ovarian pool of follicles. Techniques are now available for fertility preservation, such as cryopreservation of mature oocytes, embryos or ovarian cortical tissue. Whereas collection of mature oocytes and embryos requires at least a 2-week period, ovarian tissue may on short notice be frozen prior to treatment and can be transplanted back into women with ovarian failure. Transplanted frozen/thawed tissue supports survival and growth of follicles, giving rise to menstrual cycles and hormone production for several years. Worldwide, the procedure has resulted in the birth of 15 healthy children. Many cancer patients including girls and young women want fertility preservation, and the techniques are now being further developed and implemented in several centers.

  1. Fertility and age

    Directory of Open Access Journals (Sweden)

    Korula George

    2010-01-01

    Full Text Available The changing social scenario together with economic growth and an increase in job opportunities has to a great extent reduced gender inequality and has resulted in more and more older women seeking help from infertility clinics. Fertility and aging have always been closely linked and the age of the female partner remains the single most important factor in predicting success with treatment. Although tests for the ovarian reserve are an important informative tool and are helpful in selecting treatment options, they are poor predictors of the outcome.

  2. Collaborative work on evaluation of ovarian toxicity. 13) Two- or four-week repeated dose studies and fertility study of PPAR alpha/gamma dual agonist in female rats.

    Science.gov (United States)

    Sato, Norihiro; Uchida, Keisuke; Nakajima, Mikio; Watanabe, Atsushi; Kohira, Terutomo

    2009-01-01

    The main focus of this study was to determine the optimal dosing period in a repeated dose toxicity study based on toxic effects as assessed by ovarian morphological changes. To assess morphological and functional changes induced in the ovary by a peroxisome proliferator-activated receptor (PPAR) alpha/gamma dual agonist, the compound was administered to female rats at dose levels of 0, 4, 20, and 100 mg/kg/day in a repeated dose toxicity study for 2 or 4 weeks, and from 2 weeks prior to mating to Day 7 of pregnancy in a female fertility study. In the repeated dose toxicity study, an increase in atresia of large follicles, a decrease in corpora lutea, and an increase in stromal cells were observed in the treated groups. In addition, the granulosa cell exfoliations into antrum of large follicles and corpora lutea with retained oocyte are morphological characteristics induced by this compound, and they might be related with abnormal condition of ovulation. In the female fertility study, the pregnancy rate tended to decrease in the 100 mg/kg/day group. At necropsy, decreases in the number of corpora lutea, implantations and live embryos were noted in the 20 and 100 mg/kg/day group. No changes were observed in animals given 4 mg/kg/day. These findings indicated that histopathological changes in the ovary are important endpoints for evaluation of drugs inducing ovarian damage. In conclusion, a 2-week administration period is sufficient to detect ovarian toxicity of this test compound in the repeated dose toxicity study.

  3. Knowledge about infertility risk factors, fertility myths and illusory benefits of healthy habits in young people.

    Science.gov (United States)

    Bunting, Laura; Boivin, Jacky

    2008-08-01

    Previous research has highlighted a lack of fertility awareness in the general population especially in relation to the optimal fertile period during the menstrual cycle, incidence of infertility and duration of the reproductive life span. The current study assessed fertility knowledge more broadly in young people and investigated three areas of knowledge, namely risk factors associated with female infertility (e.g. smoking), beliefs in false fertility myths (e.g. benefits of rural living) and beliefs in the illusory benefits of healthy habits (e.g. exercising regularly) on female fertility. The sample (n = 149) consisted of 110 female and 39 male postgraduate and undergraduate university students (average age 24.01, SD = 7.81). Knowledge scores were based on a simple task requiring the participants to estimate the effect a factor would have on a group of 100 women trying to get pregnant. Items (n = 21) were grouped according to three categories: risk factors (e.g. smoking; 7 items), myths (e.g. living in countryside; 7 items) and healthy habits (e.g. being normal weight; 7 items). An analysis of variance showed a significant main effect of factor (P healthy habits (P healthy habits. We suggest that the public education campaigns should be directed to erroneous beliefs about pseudo protective factors.

  4. Evolutionary history of asexual hybrid loaches (Cobitis: Teleostei) inferred from phylogenetic analysis of mitochondrial DNA variation

    Czech Academy of Sciences Publication Activity Database

    Janko, Karel; Kotlík, Petr; Ráb, Petr

    2003-01-01

    Roč. 16, - (2003), s. 1280-1287 ISSN 1010-061X R&D Projects: GA AV ČR KSK6005114; GA ČR GA206/00/0668; GA ČR GA206/01/0989; GA AV ČR IBS5045111 Institutional research plan: CEZ:AV0Z5045916 Keywords : asexual vertebrates * Cobitis * maternal ancestry Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.010, year: 2003

  5. The role of sexual vs. asexual recruitment of Artemisia wudanica in transition zone habitats between inter-dune lowlands and active dunes in Inner Mongolia, China

    Science.gov (United States)

    Wang, Yongcui; Alberto, Busso Carlos; Jiang, Deming; Ala, Musa; Li, Xuehua; Zhou, Quanlai; Lin, Jixiang; Ren, Guohua; Jia, Lian

    2016-04-01

    Artemisia wudanica is an endemic, perennial, pioneering psammophyte species in the sand dune ecosystems of western Horqin Sand Land in northern China. However, no studies have addressed how sexual and asexual reproduction modes of A. wudanica perform at the transitional zones between active dune inter-dune lowlands and active dunes. In early spring, quadrats were randomly set up in the study area to monitor surviving seedling and/or ramet density and frequency coming from sexual/asexual reproduction of A. wudanica. Iron sticks were inserted near each quadrat to determine wind erosion intensity (WE). Additionally, soil samples were collected nearby each quadrat to test for soil moisture (SM), organic matter (OM) and pH. Surviving seedlings of A. wudanica showed an inverse response in comparison with ramets to SM, OM and WE. Soil moisture showed the most positive effect, and WE the negative effect, on surviving, sexual reproduction seedlings. Contrarily, WE had the most positive effect, and SM the negative effect, on asexual reproduction ramets. This suggests that increases in SM and decreases in WE should benefit recruitment of A. wudanica seedlings. On the contrary, ramets coming from asexual reproduction showed a different response to environmental factors in transition zone habitats. While SM was not a key constraint for the survival of seedlings, they showed a better, positive response to wind erosion environments. Overall, various study environmental parameters could be improved to foster A. wudanica invasion and settlement in the plant community through different reproductive modes, thereby promoting vegetation restoration and rehabilitation.

  6. [Fertility of the Yanomami population of Sierra Parima (Amazonas Federal Territory, Venezuela)].

    Science.gov (United States)

    Schkolnik, S

    1983-08-01

    This article presents information on the age structure and level of female fertility obtained on the basis of a sample of the Yanomami population (653 individuals) residing in the Venezuelan margin of Sierra Parima. The population observed is very young, over 50% are less than age 15, and the mean age is 18. The total fertility rate reaches 7.76 children/woman while the age distribution of rates show that fertility begins at a very early age and begins to decrease only after age 30. (author's modified)

  7. [Female age - related fertility decline: Far from the myth of the "selfish working-girl" and the "right to have a child"].

    Science.gov (United States)

    Vialle, M; Perrin, J; Amar-Hoffet, A; Boyer, P; Courbiere, B

    2016-04-01

    To study the social dimension of age-related female infertility through an analysis of three key themes: the personal life histories of infertile women over 40 years of age; representations of age and the desire to become pregnant after age 40; opinions of French legislations framing Assisted Reproductive Technologies, age limits, egg donation, and egg freezing for non-medical reasons. This qualitative sociological study was based on semi-structured interviews with infertile women over age 40 going through fertility treatments. The interviews contained three parts: personal and relationship histories; experiences related to age; opinions related to French legislation. Twenty-three interviews were conducted; each lasting between 90 to 120minutes. Far from having similar life histories, the women interviewed had very different backgrounds leading to their desire for a pregnancy after 40 years of age. From the beginning of their fertility treatments, they perceived a "race against the clock". This feeling of urgency accompanied their experiences and was related to the desire to not be too old for their future child. The women interviewed were mainly in favor of loosening French bioethical laws in order to avoid the need to travel abroad to pursue fertility treatments. The profiles studied attest to a growing gap between biological and biographical temporalities, as well as an inability of women to reduce their desire for a child. Faced with this disparity, egg donation and egg freezing were seen as practical solutions. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  8. Detailed clinical and molecular study of 20 females with Xq deletions with special reference to menstruation and fertility.

    Science.gov (United States)

    Mercer, Catherine L; Lachlan, Katherine; Karcanias, Alexandra; Affara, Nabeel; Huang, Shuwen; Jacobs, Patricia A; Thomas, N Simon

    2013-01-01

    Integrity of the long arm of the X chromosome is important for maintaining female fertility and several critical regions for normal ovarian function have been proposed. In order to understand further the importance of specific areas of the X chromosome, we describe a series of 20 previously unreported patients missing part of Xq in whom detailed phenotypic information has been gathered as well as precise chromosome mapping using array Comparative Genomic Hybridization. Features often associated with Turner syndrome were not common in our study and excluding puberty, menarche and menstruation, the phenotypes observed were present in only a minority of women and were not specific to the X chromosome. The most frequently occurring phenotypic features in our patients were abnormalities of menstruation and fertility. Larger terminal deletions were associated with a higher incidence of primary ovarian failure, occurring at a younger age; however patients with similar or even identical deletions had discordant menstrual phenotypes, making accurate genetic counselling difficult. Nevertheless, large deletions are likely to be associated with complete skewing of X inactivation so that the resulting phenotypes are relatively benign given the amount of genetic material missing, even in cases with unbalanced X;autosome translocations. Some degree of ovarian dysfunction is highly likely, especially for terminal deletions extending proximal to Xq27. In conjunction with patient data from the literature, our study suggests that loss of Xq26-Xq28 has the most significant effect on ovarian function. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  9. Mutation accumulation and fitness effects in hybridogenetic populations: a comparison to sexual and asexual systems

    Directory of Open Access Journals (Sweden)

    Bagheri Homayoun C

    2007-05-01

    Full Text Available Abstract Background Female only unisexual vertebrates that reproduce by hybridogenesis show an unusual genetic composition. They are of hybrid origin but show no recombination between the genomes of their parental species. Instead, the paternal genome is discarded from the germline prior to meiosis, and gametes (eggs only contain solely unrecombined maternal genomes. Hence hybridogens only transmit maternally inherited mutations. Hybridity is restored each generation by backcrossing with males of the sexual parental species whose genome was eliminated. In contrast, recombining sexual species propagate an intermixed pool of mutations derived from the maternal and paternal parts of the genome. If mutation rates are lower in female gametes than males, it raises the possibility for lower mutation accumulation in a hybridogenetic population, and consequently, higher population fitness than its sexual counterpart. Results We show through Monte-Carlo simulations that at higher male to female mutation ratios, and sufficiently large population sizes, hybridogenetic populations can carry a lower mutation load than sexual species. This effect is more pronounced with synergistic forms of epistasis. Mutations accumulate faster on the sexual part of the genome, and with the purifying effects of epistasis, it makes it more difficult for mutations to be transmitted on the clonal part of the genome. In smaller populations, the same mechanism reduces the speed of Muller's Ratchet and the number of fixed mutations compared to similar asexual species. Conclusion Since mutation accumulation can be less pronounced in hybridogenetic populations, the question arises why hybridogenetic organisms are so scarce compared to sexual species. In considering this, it is likely that comparison of population fitnesses is not sufficient. Despite competition with the sexual parental species, hybrid populations are dependent on the maintenance of – and contact with – their

  10. Family structure and fertility in Taiwan: an extension and modification of Caldwell's wealth flows theory.

    Science.gov (United States)

    Hsuing, P C

    1988-06-01

    Based on the data from a nationwide survey of labor force participation conducted in 1985 by the Office of the Directorate-General of Budget, Accounting and Statistics, Executive Yuan, Republic of China, this project tries to modify Caldwell's Wealth Flows Theory in order to analyze fertility behavior of married women. Caldwell's Wealth Flows Theory indicates that a patriarchal family has a significant effect on fertility. Unless the patriarchal family structure is replaced by a nuclear family system, he claims, fertility levels will remain relatively high in developing countries. However, he does not discuss social factors which may influence the process of change in the family structure and which factors in the patriarchal family may influence fertility. To make up this shortcoming, this paper shows that female educational level, employment patterns, and occupational prestige brings about change in the family structure. This research also indicates that women with higher education and occupational prestige have lower fertility. In addition, it finds that female occupational status is a main factor to bring about change in the family structure. (author's)

  11. Robust inducible Cre recombinase activity in the human malaria parasite Plasmodium falciparum enables efficient gene deletion within a single asexual erythrocytic growth cycle.

    Science.gov (United States)

    Collins, Christine R; Das, Sujaan; Wong, Eleanor H; Andenmatten, Nicole; Stallmach, Robert; Hackett, Fiona; Herman, Jean-Paul; Müller, Sylke; Meissner, Markus; Blackman, Michael J

    2013-05-01

    Asexual blood stages of the malaria parasite, which cause all the pathology associated with malaria, can readily be genetically modified by homologous recombination, enabling the functional study of parasite genes that are not essential in this part of the life cycle. However, no widely applicable method for conditional mutagenesis of essential asexual blood-stage malarial genes is available, hindering their functional analysis. We report the application of the DiCre conditional recombinase system to Plasmodium falciparum, the causative agent of the most dangerous form of malaria. We show that DiCre can be used to obtain rapid, highly regulated site-specific recombination in P. falciparum, capable of excising loxP-flanked sequences from a genomic locus with close to 100% efficiency within the time-span of a single erythrocytic growth cycle. DiCre-mediated deletion of the SERA5 3' UTR failed to reduce expression of the gene due to the existence of alternative cryptic polyadenylation sites within the modified locus. However, we successfully used the system to recycle the most widely used drug resistance marker for P. falciparum, human dihydrofolate reductase, in the process producing constitutively DiCre-expressing P. falciparum clones that have broad utility for the functional analysis of essential asexual blood-stage parasite genes. © 2013 John Wiley & Sons Ltd.

  12. Socioeconomic differences in the unemployment and fertility nexus: Evidence from Denmark and Germany.

    Science.gov (United States)

    Kreyenfeld, Michaela; Andersson, Gunnar

    2014-09-01

    Studies that have investigated the role of unemployment in childbearing decisions have often shown no or only barely significant results. We argue that many of these "non-findings" may be attributed to a neglect of group-specific differences in behavior. In this study, we examine how the association of unemployment and fertility varies by socio-demographic subgroups using data from the German Socio-Economic Panel (GSOEP) and from Danish population registers. We find that male unemployment is related to a postponement of first and second childbearing in both countries. The role of female unemployment is less clear at these two parities. Both male and female unemployment is positively correlated with third birth risks. More importantly, our results show that there are strong educational gradients in the unemployment and fertility nexus, and that the relationship between unemployment and fertility varies by socioeconomic group. Fertility tends to be lower during periods of unemployment among highly educated women and men, but not among their less educated counterparts. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Culture: an empirical investigation of beliefs, work, and fertility

    OpenAIRE

    Raquel Fernandez; Alessandra Fogli

    2005-01-01

    We study the effect of culture on important economic outcomes by using the 1970 Census to examine the work and fertility behaviour of women 30-40 years old, born in the US, but whose parents were born elsewhere. We use past female labour force participation and total fertility rates from the country of ancestry as our cultural proxies. These variables should capture, in addition to past economic and institutional conditions, the beliefs commonly held about the role of women in society, i.e. c...

  14. Marijuana, the Endocannabinoid System and the Female Reproductive System.

    Science.gov (United States)

    Brents, Lisa K

    2016-06-01

    Marijuana use among women is highly prevalent, but the societal conversation on marijuana rarely focuses on how marijuana affects female reproduction and endocrinology. This article reviews the current scientific literature regarding marijuana use and hypothalamic-pituitary-ovarian (HPO) axis regulation, ovarian hormone production, the menstrual cycle, and fertility. Evidence suggests that marijuana can reduce female fertility by disrupting hypothalamic release of gonadotropin releasing hormone (GnRH), leading to reduced estrogen and progesterone production and anovulatory menstrual cycles. Tolerance to these effects has been shown in rhesus monkeys, but the effects of chronic marijuana use on human female reproduction are largely unknown. Marijuana-induced analgesia, drug reinforcement properties, tolerance, and dependence are influenced by ovarian hormones, with estrogen generally increasing and progesterone decreasing sensitivity to marijuana. Carefully controlled regulation of the Endocannabinoid System (ECS) is required for successful reproduction, and the exogenous cannabinoids in marijuana may disrupt the delicate balance of the ECS in the female reproductive system.

  15. Female fitness optimum at intermediate mating rates under traumatic mating.

    Directory of Open Access Journals (Sweden)

    Rolanda Lange

    Full Text Available Traumatic mating behaviors often bear signatures of sexual conflict and are then typically considered a male strategy to circumvent female choice mechanisms. In an extravagant mating ritual, the hermaphroditic sea slug Siphopteron quadrispinosum pierces the integument of their mating partners with a syringe-like penile stylet that injects prostate fluids. Traumatic injection is followed by the insertion of a spiny penis into the partner's gonopore to transfer sperm. Despite traumatic mating, field mating rates exceed those required for female fertilization insurance, possibly because costs imposed on females are balanced by direct or indirect benefits of multiple sperm receipt. To test this idea, we exposed animals to a relevant range of mating opportunity regimes and assessed the effects on mating behavior and proxies of female fitness. We find penis intromission duration to decrease with mating rates, and a female fecundity maximum at intermediate mating rates. The latter finding indicates that benefits beyond fertilization insurance can make higher mating rates also beneficial from a female perspective in this traumatically mating species.

  16. Sexuality and fertility outcomes after hand sewn versus stapled ileal pouch anal anastomosis for ulcerative colitis.

    Science.gov (United States)

    Harnoy, Yann; Desfourneaux, Véronique; Bouguen, Guillaume; Rayar, Michel; Meunier, Bernard; Siproudhis, Laurent; Boudjema, Karim; Sulpice, Laurent

    2016-01-01

    Ileal pouch anal anastomosis (IPAA) may alter sexuality and fertility in women. The laparoscopic approach seems to reduce infertility rates in women after IPAA. However, the impact of hand sewn versus stapled IPAA on sexuality and fertility has never been assessed in patients with ulcerative colitis (UC). The objective of this study was to analyze the impact of the IPAA technique on sexuality and fertility in UC. All UC patients who underwent an IPAA between May 1996 and April 2011 were included. The patients answered mailed questionnaires including sexuality validated questionnaires and fertility questionnaires. The risk factors of sexual dysfunction were explored. A total of 135 patients were included. Eighty-eight patients (65%) answered the questionnaires. Their mean age and follow-up were 37.2 ± 13.4 y and 109.7 ± 57.5 mo. The rates of female and male sexual dysfunction were 50% and 29%, respectively. Intestinal transit disorders were identified as risk factors in both men and women and anastomotic stricture in women sexual dysfunction, in univariate analyses. The IPAA technique did not impact sexual function in women but there was a trend for less erectile dysfunction after hand sewn IPAA (16.7% versus 44.4%). The fertility rate was 47% in women and 75% in men, with a trend for a better fertility in women after hand sewn IPAA (P = 0.07). In this preliminary study, the hand sewn or stapled IPAA technique did not impact the sexuality or fertility outcomes of UC patients, but there was a trend for better female fertility and male erectile function after hand sewn IPAA. Intestinal transit disorders contributed to male and female sexual dysfunction after IPAA. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Discourses Governing Lesbian, Gay, Bisexual, Transgender, Queer, Intersex, and Asexual Teachers' Disclosure of Sexual Orientation and Gender History

    Science.gov (United States)

    Bower-Phipps, Laura

    2017-01-01

    Significant progress has been made in equal rights for lesbian, gay, bisexual, transgender, queer, intersex, and asexual (LGBTQIA) individuals, yet schools remain institutions where sexual and gender diversity are marginalized and/or silenced. Queer theory, a non-linear theory that disrupts dominant beliefs about gender and sexuality and what…

  18. Long-term effects of GnRH agonists on fertility and behaviour

    DEFF Research Database (Denmark)

    Goericke-Pesch, Sandra Kathrin

    2017-01-01

    ; a significant positive effect in reducing sexual behaviour and libido, hypersexuality, intermale dominance and excessive territorial urine marking has been described. Rates of improvement of the respective behaviour are comparable to those after surgical castration, making GnRH A-SRI a valuable option...... and behaviour have by now been shown to be fully reversible. Knowledge in females is more limited, and particularly, the initial induction of a possibly fertile oestrus and individual variation in duration of efficacy remain problems in bitches and queens treated for suppression of fertility. However, long......-term suppression of oestrous cycle and fertility seems to be possible with induced effects shown to be reversible including restoration of normal fertility after the end of efficacy/GNRH A-SRI removal....

  19. Effect of Consuming Iodized Salt on Fertility Indices in Male Adult Rats

    Directory of Open Access Journals (Sweden)

    M. Mehrabani Natanzi

    2017-06-01

    Full Text Available Introduction: Today about 27.4 percent of female 15-44 years and 1 percent of female in fertility age are affected by infertility. Iodine is a rare element that is essential for the synthesis of thyroid hormones. Concentration of the thyroid hormones in blood under the influence of iodine intake and changes in thyroid hormones levels interact with reproductive system. Today, all the people of Iran consuming iodized salt regardless of iodine status in their body. In this study according to high prevalence of the infertility among young couples, iodized salt intake on fertility in male rats were investigated. Materials and Methods: In this study 20 male and 20 female adult Wistar rats were used. Twenty male adult Wistar rats were randomly divided into 2 groups. Including the control group and treatment group that received iodine and female adult Wistar were fed with a regular diet. Five male rats from each group were killed at the end of the fourth weeks in order to evaluate the possible effect of iodized salt on sperm analysis and weight of testis. After a month, male and female rats were placed in pairs in separate cages and their offspring were investigated in terms of number, gender and health. Results: The result of this study showed that the number of healthy offspring of treated male rats was significantly lower than the control group. Conclusion: Due to the negative effect of excessive iodine intake on fertility rate, it is recommended to couples to perform functional tests of their thyroid glands before intake of iodized salts.

  20. Intentions and attitudes towards parenthood and fertility awareness among Chinese university students in Hong Kong: a comparison with Western samples.

    Science.gov (United States)

    Chan, C H Y; Chan, T H Y; Peterson, B D; Lampic, C; Tam, M Y J

    2015-02-01

    What are the levels of awareness regarding female fertility and the intentions and attitudes towards parenthood among Chinese university students in Hong Kong compared with their counterparts in the West? Chinese university students in Hong Kong were similarly over-optimistic about the age-related fertility decline, although they were less inclined to have children and undergo fertility treatment compared with their Western counterparts. Past studies of highly educated young adults in Europe and the USA have found that they are not sufficiently aware of the age-related decline in female fertility, and falsely believe that advanced reproductive treatments such as IVF will overcome fertility problems associated with age. Little is known about the perceptions of Chinese students in Hong Kong, a modernized Chinese city where the fertility rate is among the lowest in the world. An online cross-sectional survey of Chinese university students in Hong Kong was conducted in 2013. Results were compared with two similar studies in Sweden and the USA. A total of 367 university students in Hong Kong (275 female, 92 male; mean age 23) responded to an e-mail invitation to participate in an online survey. Intentions and attitudes towards parenthood and awareness regarding female fertility were assessed using the Swedish Fertility Awareness Questionnaire. Like their Western counterparts, a large proportion of Chinese university students underestimated the age-related fertility decline (92%) and overestimated the fertility treatment success rate (66%). However, they were less inclined to have children, were more aware of and less concerned with infertility and were less motivated to seek solutions in the event of a fertility problem. These comparisons were significant at P International comparisons warrant caution because the Hong Kong sample was older than the US sample (mean age 20), but not older than the Sweden sample (mean age 24). While this study was consistent with past

  1. Sperm-storage defects and live birth in Drosophila females lacking spermathecal secretory cells.

    Directory of Open Access Journals (Sweden)

    Sandra L Schnakenberg

    2011-11-01

    Full Text Available Male Drosophila flies secrete seminal-fluid proteins that mediate proper sperm storage and fertilization, and that induce changes in female behavior. Females also produce reproductive-tract secretions, yet their contributions to postmating physiology are poorly understood. Large secretory cells line the female's spermathecae, a pair of sperm-storage organs. We identified the regulatory regions controlling transcription of two genes exclusively expressed in these spermathecal secretory cells (SSC: Spermathecal endopeptidase 1 (Send1, which is expressed in both unmated and mated females, and Spermathecal endopeptidase 2 (Send2, which is induced by mating. We used these regulatory sequences to perform precise genetic ablations of the SSC at distinct time points relative to mating. We show that the SSC are required for recruiting sperm to the spermathecae, but not for retaining sperm there. The SSC also act at a distance in the reproductive tract, in that their ablation: (1 reduces sperm motility in the female's other sperm-storage organ, the seminal receptacle; and (2 causes ovoviviparity--the retention and internal development of fertilized eggs. These results establish the reproductive functions of the SSC, shed light on the evolution of live birth, and open new avenues for studying and manipulating female fertility in insects.

  2. Prevalence of Child Marriage and its Impact on the Fertility and Fertility Control Behaviors of Young Women in India

    Science.gov (United States)

    Raj, Anita; Saggurti, Niranjan; Balaiah, Donta; Silverman, Jay G.

    2009-01-01

    Objectives Child marriage in India is considered a major barrier to the nation's social and economic development, as well as a major women's health concern. The current study assesses prevalence of child marriage (i.e., marriage prior to the national legal age of 18 years) among young adult women in India, and associations between child marriage and women's fertility and fertility control behaviors. Study Design Cross-sectional analyses of a nationally representative household sample of Indian women ages 16-49 years (N=124,385) collected in 2005-2006 via the National Family Health Survey-3. Participants Analyses were restricted to women age 20-24 years (n=22,807) and the subsample of ever married women aged 20-24 years (n=14,628). Data Analysis Prevalence estimates of child marriage were produced for all women 20-24 years. Using the ever married subsample, simple regression models, models adjusted for demographics, and models adjusted for demographics and duration of marriage were constructed to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for the associations between child marriage and both fertility and fertility control outcomes. Fertility and Fertility Control Outcomes No contraception prior to childbirth, childbirth within first year of marriage, high fertility (3 or more births), history of recent rapid repeat childbirth, unwanted pregnancy, and female sterilization. Results Child marriage was reported by 44.5% of Indian women ages 20-24 years; 22.6% reported marriage prior to age 16 years, and 2.6% were married prior to age 13 years. Child marriage was significantly associated with women's increased risk for no contraceptive use prior to first childbirth (AOR=1.37, 95% CI=1.22, 1.54), high fertility (AOR=7.40, 95% CI=6.45, 8.50), history of rapid repeat childbirth (AOR=3.00, 95% CI=2.74, 3.29), multiple unwanted pregnancies (AOR=2.36, 95% CI=1.90, 2.94), pregnancy termination (AOR=1.22; 95% CI=1.06, 1.41) and female sterilization (AOR=5

  3. Polymorphism and methylation patterns in Agave tequilana Weber var. 'Azul' plants propagated asexually by three different methods.

    Science.gov (United States)

    Díaz-Martínez, Miriam; Nava-Cedillo, Alejandro; Guzmán-López, José Alfredo; Escobar-Guzmán, Rocío; Simpson, June

    2012-04-01

    Genetic variation in three forms of asexually propagated Agave tequilana Weber var. 'Azul' plants namely offsets, bulbils and in vitro cultured individuals was studied by AFLP analysis. Low levels of variation were observed between mother plants and offsets and a higher level between mother plant and bulbils. Families obtained from commercial plantations showed lower levels of variation in comparison to families grown as ornamentals. No variation was observed between the original explant and four generations of in vitro cultured plants. Epigenetic variation was also studied by analyzing changes in methylation patterns between mother plants and offspring in each form of asexual reproduction. Offsets and bulbils showed an overall decrease in methylation whereas in vitro cultured plants showed patterns specific to each generation: Generations 1 and 4 showed overall demethylation whereas Generations 2 and 3 showed increased methylation. Analysis of ESTs associated with transposable elements revealed higher proportions of ESTs from Ty1-copia-like, Gypsy and CACTA transposable elements in cDNA libraries obtained from pluripotent tissue suggesting a possible correlation between methylation patterns, expression of transposable element associated genes and somaclonal variation. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  4. Collection of gametes from live axolotl, Ambystoma mexicanum, and standardization of in vitro fertilization.

    Science.gov (United States)

    Mansour, N; Lahnsteiner, F; Patzner, R A

    2011-01-15

    This study established the first protocol for collection of gametes from live axolotl, Ambystoma mexicanum, by gentle abdominal massage and in vitro fertilization. To stimulate spermiation and ovulation, human chorionic gonadotrophin (hCG) and Ovopel pellets, which are commercially used to stimulate spawning in fish, were tested. The hCG was more effective than Ovopel pellets and yielded a higher semen volume in the injected males and a shorter response time in the females. Collected semen by this method was already motile and fertile. Fertile eggs could be collected in 3-4 successive collection times after the female has started the typical spawning behaviour. The fertilization condition that yielded the highest hatching rate was mixing semen with eggs before the addition of a fertilization saline solution (20 mmol/l NaCl, 1 mmol/l KCl, 1 mmol/l Mg(2)SO(4), 1 mmol Ca(2)Cl, 3 mmol NaHCO(3), 10 mmol/l Tris, pH 8.5 - Osmolality = 65 mosmol/kg). When the pH of the fertilization solution was increased to ≥ 10, the hatching rate was significantly increased. The use of fertilization solutions with osmolalities of ≥ 150 and ≥ 182 were accompanied with a significant decrease in hatching rates and the appearance of deformed larvae, respectively. In conclusion, a reliable protocol for gamete collection from live axolotl is established as a laboratory model of in vitro fertilization for urodele amphibians. This protocol may be transferable to endangered urodeles. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. A Global Survey of ATPase Activity in Plasmodium falciparum Asexual Blood Stages and Gametocytes

    Energy Technology Data Exchange (ETDEWEB)

    Ortega, Corrie; Frando, Andrew; Webb-Robertson, Bobbie-Jo; Anderson, Lindsey N.; Fleck, Neil; Flannery, Erika L.; Fishbaugher, Matthew; Murphree, Taylor A.; Hansen, Joshua R.; Smith, Richard D.; Kappe, Stefan H. I.; Wright, Aaron T.; Grundner, Christoph

    2017-10-27

    Effective malaria control and elimination in hyperendemic areas of the world will require treatment of disease-causing Plasmodium falciparum (Pf) blood stage infection but also blocking parasite transmission from humans to mosquito to prevent disease spread. Numerous antimalarial drugs have become ineffective due to parasite drug resistance and many currently used therapies do not kill gametocytes, highly specialized sexual parasite stages with distinct physiology that are necessary for transmission from the human host to the mosquito vector. Further confounding next generation drug development against Pf is the lack of known biochemical activity for most parasite gene products as well as the unknown metabolic needs of non-replicating gametocyte. Here, we take a systematic activity-based proteomics approach to survey the large and druggable ATPase family that is associated with replicating blood stage asexual parasites and transmissible gametocytes. We experimentally confirm existing annotation and predict ATPase function for 38 uncharacterized proteins. ATPase activity broadly changes during the transition from asexual schizonts to gametocytes, indicating altered metabolism and regulatory roles of ATPases specific for each lifecycle stage. By mapping the activity of ATPases associated with gametocytogenesis, we assign biochemical activity to a large number of uncharacterized proteins and identify new candidate transmission blocking targets.

  6. Cohort fertility and educational expansion in the Czech Republic during the 20th century

    Directory of Open Access Journals (Sweden)

    Krystof Zeman

    2018-05-01

    Full Text Available Background: During the 20th century the Czech Republic went through profound changes in female employment, gender roles, population and family policies, and public childcare. The educational structure of the female population changed tremendously. At the same time, completed cohort fertility fluctuated between 1.8 and 2.2 children per woman. Objective: This article analyses the changes in the level of completed cohort fertility by education, during educational expansion in the Czech population under the economic, cultural, and institutional background of the state socialist regime, and after its breakdown. Methods: The changes in the level of completed cohort fertility by education are analysed by means of decomposition, complemented by the analysis of parity composition. Results: During the 20th century, education-specific completed cohort fertility increased, rather than declined. Fertility levels converged upwards, contributing to high uniformity within educational categories. The overall changes in fertility levels were driven by changes in the educational structure. These trends resulted in the dominance of the two-child family, while large families were disappearing and childlessness dropped to the biological minimum. Conclusions: An egalitarian economic system with traditional family-friendly policies, in combination with a family-unfriendly labour market, developed into a male breadwinner model of low gender equity. Future family policies should focus on the reconciliation of work and family. Contribution: The study contributes to the discussion on links between education and fertility, adding a new picture to the mosaic of country-level analyses. The Czech Republic is an example of a country with high educational homogeneity of fertility behaviour where the education-specific levels of fertility converged upwards.

  7. Effect of season on reproductive behaviors and fertilization success in cavies (Cavia aperea).

    Science.gov (United States)

    Hribal, Romy; Rübensam, Kathrin; Bernhardt, Sandra; Jewgenow, Katarina; Guenther, Anja

    2018-04-05

    Finding the optimal timing for breeding is crucial for small mammals to ensure survival and maximize lifetime reproductive success. Species living in temperate regions therefore often restrict breeding to seasons with favorable food and weather conditions. Although caviomorph rodents such as guinea pigs are described as non-seasonal breeders, a series of recent publications has shown seasonal adaptations in litter size, offspring birth mass and maternal investment. Here, we aim to test if seasonal patterns of litter size variation found in earlier studies, are mediated by seasonal differences in female estrus length, fertilization rate and mating behavior. The female estrus period was longer in fall compared to all other seasons (p < 0.001), frequently lasting 7-9 days while estrus in spring usually lasted less than 2 days. In fall, females mated later during estrus (p < 0.001), resulting in reduced fertilization rates (p < 0.001). Fertilization rate was well above 95% in summer while it dropped to less than 85% in fall and winter. While none of the male mating characteristics such as number and duration of copulations differed across seasons, the number of mating bouts was reduced in fall (p = 0.04). Finally, the developmental stages of flushed embryos were more diverse in spring and summer compared to fall and winter. These results suggest that seasonal differences in fertilization rate and quality of implanted embryos are mediated by female estrus length and timing and intensity of mating behavior. Together, these effects contribute to the observed differences in litter size across seasons. Copyright © 2018 Elsevier Inc. All rights reserved.

  8. Measuring sperm backflow following female orgasm: a new method

    Science.gov (United States)

    King, Robert; Dempsey, Maria; Valentine, Katherine A.

    2016-01-01

    Background Human female orgasm is a vexed question in the field while there is credible evidence of cryptic female choice that has many hallmarks of orgasm in other species. Our initial goal was to produce a proof of concept for allowing females to study an aspect of infertility in a home setting, specifically by aligning the study of human infertility and increased fertility with the study of other mammalian fertility. In the latter case - the realm of oxytocin-mediated sperm retention mechanisms seems to be at work in terms of ultimate function (differential sperm retention) while the proximate function (rapid transport or cervical tenting) remains unresolved. Method A repeated measures design using an easily taught technique in a natural setting was used. Participants were a small (n=6), non-representative sample of females. The introduction of a sperm-simulant combined with an orgasm-producing technique using a vibrator/home massager and other easily supplied materials. Results The sperm flowback (simulated) was measured using a technique that can be used in a home setting. There was a significant difference in simulant retention between the orgasm (M=4.08, SD=0.17) and non-orgasm (M=3.30, SD=0.22) conditions; t (5)=7.02, p=0.001. Cohen's d=3.97, effect size r=0.89. This indicates a medium to small effect size. Conclusions This method could allow females to test an aspect of sexual response that has been linked to lowered fertility in a home setting with minimal training. It needs to be replicated with a larger sample size. PMID:27799082

  9. EFFECTS OF SILVER NANOPARTICLES IN SOLUTION AND LIPOSOMAL FORM ON SOME BLOOD PARAMETERS IN FEMALE RABBITS DURING FERTILIZATION AND EARLY EMBRYONIC DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Vasyl Syrvatka

    2014-02-01

    Full Text Available Silver nanoparticles are the most rapidly growing classes of nanoproducts. In this study, we investigated the influence of subcutaneous injections of silver nanoparticles in solution and in liposomal form on hematological and biochemical parameters of blood of New Zealand White rabbits during hormonal treatment, fertilization and early embryonic development. The females treated by free silver nanoparticles and silver nanoparticles in liposomal form received silver at a dose of 10 µg/kg/day in 5 % glucose solution during 28 days. Blood sampling was done four times: the day before the compounds administration; on day 7 after the compounds administration; in the period after hormonal induction and fertilization and on the 14th day of pregnancy. Our results showed changes in some biochemical (lactate dehydrogenase activities, progesterone and estradiol concentration, malondialdehyde level, etc. and hematological (hematocrit, mean cell volume, mean corpuscular hemoglobin concentration, etc. parameters under the influence of hormonal treatment and pregnancy. The concentration of progesterone showed significantly higher values (P˂0.05 on GDs 1 in S group than in C group. The percentage of neutrophils was significantly higher in SG rabbits after 7 days of silver nanoparticles administration than that in the CG. There were no significant changes in red blood cells parameters, platelets, and activity of some ferments (ALP, AST, ALT, LDH, GGT between control and silver groups during the entire period of experiment. In conclusion, the hematological and biochemical values of blood obtained in the given study showed that free silver nanoparticles and silver nanoparticles in liposomal form in the investigated concentrations had no toxic effect on hormonal treatment, fertilization and early embryonic development in New Zealand White rabbits.

  10. Decision-making in female fertility preservation is balancing the expected burden of fertility preservation treatment and the wish to conceive

    NARCIS (Netherlands)

    Baysal, O.; Bastings, L.; Beerendonk, C.C.M.; Postma, S.A.; Hout, J. in't; Verhaak, C.M.; Braat, D.D.M.; Nelen, W.L.D.M.

    2015-01-01

    STUDY QUESTION: What are the decisive factors in fertility preservation (FP) decision-making in young women scheduled for gonadotoxic therapy? SUMMARY ANSWER: FP decision-making in young women scheduled for gonadotoxic therapy is mainly based on weighing two issues: the intensity of the wish to

  11. Status of fertility control in Egypt.

    Science.gov (United States)

    Hefnawi, F I

    1982-01-01

    The concern for fertility control is not alien to the cultural and religious heritage of Egypt. Historically, Egyptian interest in fertility dates to the Pharoahs. Contraceptive recipes written at least 15-18 centuries B.C. have been found. Romans may have borrowed some of the more effective methods from Egypt when it became part of the Roman Empire as evidenced by the decline in size of aristocratic Roman families at the beginning of the Christian era. Muslim conquerors of Egypt encouraged fertility control. In the 9th century differences of opinion about the legality of contraception appeared among the interpreters of Islamic law. Some methods found in the writings of Muslim doctors as al-Razi and Avicenna still survive in the folk medicine of Egypt. In modern times use of barrier methods of contraception were encouraged by family planning organizations in Egypt. The medical profession was not deeply involved since these methods did not require much medical assistance. In 1936 a religiouss verdict declared contraception to be a lawful act of Islam. National programs in family planning in the 1960's encouraged the use of the Lippes Loop IUD. The medical problem of blood loss associated with the IUD caused anxiety because of the high incidence of anemia in the female Egyptian population. There was also a cultural limitation on the wide use of the IUD. "Spotting" due to the IUD resulted in females being ritually unclean and therefore unfit to pray or observe the Islamic fast. The Pill, initially favored caused complications due to its effect on breast milk which is the universal source of nutrition for infants in Egypt. Replacement of the Pill by depo-provera injections during the post partum period of lactation is a practical solution. Permanent sterilization is limited to females and only performed when medically indicated. Abortion is illegal and permitted only as a therapeutic measure.

  12. Which female cancer patients fail to receive fertility counseling before treatment in the state of Georgia?

    Science.gov (United States)

    Chin, Helen B; Howards, Penelope P; Kramer, Michael R; Mertens, Ann C; Spencer, Jessica B

    2016-12-01

    To assess which characteristics are associated with failure to receive fertility counseling among a cohort of young women diagnosed with cancer. Population-based cohort study. Not applicable. A total of 1,282 cancer survivors, of whom 1,116 met the inclusion criteria for the analysis. None. The main outcome in this study was whether or not women reported receiving any information at the time of their cancer diagnosis on how cancer treatment might affect their ability to become pregnant. Forty percent of cancer survivors reported that they did not receive fertility counseling at the time of cancer diagnosis. Women were more likely to fail to receive counseling if they had only a high school education or less or if they had given birth. Cancer-related variables that were associated with a lack of counseling included not receiving chemotherapy as part of treatment and diagnosis with certain cancer types. Counseling about the risk of infertility and available fertility preservation options is important to cancer patients. Additionally, counseling can make women aware of other adverse reproductive outcomes, such as early menopause and its associated symptoms. Less-educated women and parous women are at particular risk of not getting fertility-related information. Programs that focus on training not just the oncologist, but also other health care providers involved with cancer care, to provide fertility counseling may help to expand access. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  13. Signal content of red facial coloration in female mandrills (Mandrillus sphinx).

    Science.gov (United States)

    Setchell, Joanna M; Wickings, E Jean; Knapp, Leslie A

    2006-09-22

    Studies of secondary sexual ornamentation and its maintenance by sexual selection tend to focus on males; however, females may also possess showy ornaments. For example, female mandrills possess facial coloration that ranges from black to bright pink. We used fortnightly photographs of 52 semi-free-ranging females aged above 3years over 19 months to evaluate whether colour conveys information concerning female competitive ability, reproductive quality, age or reproductive status. Colour was not related to female rank or quality (body mass index, age at first birth or mean inter-birth interval); however, colour did increase significantly with age and primiparous females were darker than multiparous females. Colour may therefore signal reproductive quality, as younger females are less fertile and produce smaller offspring. Colour was brighter during the follicular phase than during the luteal phase, suggesting that it may signal fertility. Colour also varied across gestation and peaked at four and eight weeks post-parturition, suggesting that it may signal approaching parturition and lactation. Future studies should examine the relationship between colour and the menstrual cycle in more detail, the hormonal basis of female colour, and determine experimentally whether mandrills of both sexes attend to differences in colour between and within females.

  14. Can public policies sustain fertility in the Nordic countries?: Lessons from the past and questions for the future

    Directory of Open Access Journals (Sweden)

    Marit Rønsen

    2010-03-01

    Full Text Available The collective evidence of past research indicates that Nordic social welfare policies have had positive impacts on fertility. Yet, some patterns cause concern. One concern is that the good recuperation at cohort level partly is explained by relatively high fertility levels among women educated for female-dominated jobs with extensive part-time work. One may therefore question whether the present development is compatible with gender equality. Another concern is a more socially selective entry into fatherhood. Based on updated analyses of female as well as male fertility trends in Norway we address these issues, focussing especially on associations with educational level and field.

  15. Oocyte cryopreservation for fertility preservation in postpubertal female children at risk for premature ovarian failure due to accelerated follicle loss in Turner syndrome or cancer treatments.

    Science.gov (United States)

    Oktay, K; Bedoschi, G

    2014-12-01

    To preliminarily study the feasibility of oocyte cryopreservation in postpubertal girls aged between 13 and 15 years who were at risk for premature ovarian failure due to the accelerated follicle loss associated with Turner syndrome or cancer treatments. Retrospective cohort and review of literature. Academic fertility preservation unit. Three girls diagnosed with Turner syndrome, 1 girl diagnosed with germ-cell tumor. and 1 girl diagnosed with lymphoblastic leukemia. Assessment of ovarian reserve, ovarian stimulation, oocyte retrieval, in vitro maturation, and mature oocyte cryopreservation. Response to ovarian stimulation, number of mature oocytes cryopreserved and complications, if any. Mean anti-müllerian hormone, baseline follical stimulating hormone, estradiol, and antral follicle counts were 1.30 ± 0.39, 6.08 ± 2.63, 41.39 ± 24.68, 8.0 ± 3.2; respectively. In Turner girls the ovarian reserve assessment indicated already diminished ovarian reserve. Ovarian stimulation and oocyte cryopreservation was successfully performed in all female children referred for fertility preservation. A range of 4-11 mature oocytes (mean 8.1 ± 3.4) was cryopreserved without any complications. All girls tolerated the procedure well. Oocyte cryopreservation is a feasible technique in selected female children at risk for premature ovarian failure. Further studies would be beneficial to test the success of oocyte cryopreservation in young girls. Copyright © 2014 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

  16. Fertility and social interaction at the workplace: Does childbearing spread among colleagues?

    Science.gov (United States)

    Pink, Sebastian; Leopold, Thomas; Engelhardt, Henriette

    2014-09-01

    This research investigates whether colleagues' fertility influences women's transitions to parenthood. We draw on Linked-Employer-Employee data (1993-2007) from the German Institute for Employment Research comprising 33,119 female co-workers in 6579 firms. Results from discrete-time hazard models reveal social interaction effects on fertility among women employed in the same firm. In the year after a colleague gave birth, transition rates to first pregnancy double. This effect declines over time and vanishes after two years. Further analyses suggest that the influence of colleagues' fertility is mediated by social learning. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Kerala reaps low fertility dividends.

    Science.gov (United States)

    1992-01-01

    Unlike much of India, the state of Kerala has promoted the development of human resources, resulting in lower fertility rates. If current UN projections are correct, India will overtake China as the most populous nation in the world by 2025. Within India, however, great differences exist in fertility rates, reflecting the level of commitment from state governments. In India, state governments control much of the policy and spending on health, education, etc. While the state of Kerala has been among the most committed to human resource development in the developing world, India's 5 northern states (Rajasthan, Uttar Pradesh, Madhya Pradesh, Bihar, and Orissa) have been among the least committed. As a result, Kerala's fertility rate has fallen to 2.3 children/women--a rate lower than that of Thailand, China, the formers USSR, or Ireland. Kerala has a contraceptive prevalence rate 3 times the national average and the lowest infant mortality rate in all of India--only 26/1000 live births (infant mortality is 4-5 times higher in the 5 northern states). Only 27% of Kerala's population lives in poverty, compared to 34-49.5% in the northern states. Real incomes and industrialization have been growing faster in Kerala. And industrialization does not appear to have come at the expense of the environment. 2 factors are responsible for Kerala' accomplishments: 1) State government support of human development--the state has invested in health, education, and has conducted a land reform benefiting 3 million landless peasants. 2) The status of women--in Kerala, women are viewed as an asset, not a liability (as in the north). Kerala's female literacy is 66%, compared to 11-21% in the northern states. Kerala also enjoys the highest level of female labor force participation (35%) anywhere in India.

  18. Women health seeking behaviour and its influence on their fertility performance: utilization of prenatal and postnatal care

    International Nuclear Information System (INIS)

    Abbasi, S.U.R.S.; Nawaz, S.; Yousif, F.N.; Zafar, M.I.

    2008-01-01

    Evidences regarding the effect of pre- and postnatal care on women fertility were scanty and rarely explored in countries struggling to curtail high population growth. This specialized health care enabled women for regular consultation with the health professionals and discussions with fellow women visiting clinics. It enhances their awareness, knowledge and understating about mother-child welfare during pre- and postnatal cares. This improves their control on subsequent fertility and underlines the need to explore the hidden dimension of female fertility. A doctoral level study on the determinants of marital fertility was conducted in district Faisalabad, Pakistan. It also examined the influence of pre- and postnatal care on family size in terms of children ever born. A random sample of 1051 married women was studied from 18 villages and 18 urban localities through formal survey. The study concluded that at least 5 prenatal and 2 postnatal cares proved effective in reducing marital fertility. Improved women access to specialized care, motivation through mass media, involvement of female representatives at union council level and effective use of primary support groups are the measures suggested to enhance women control on their fertility in Pakistan. (author)

  19. Modification of fecundity and fertility during oogenesis by γ radiation and/or ozone with a cytological analysis in the ectoparasitic wasp, Habrobracon juglandis (Ashmead)

    International Nuclear Information System (INIS)

    Ofuoku, E.E.

    1984-01-01

    In Experiment I, adult female wasps were exposed to ozone for 0, 2, 4, 6, 8, 10, 12, 16, 24, and 27 h. The results indicated that the 27 h of ozone exposure produced 100% lethality on the first day. Exposures below 27 h progressively decreased life span with increasing length of exposure. In Experiment II A, adult virgin Habrobracon females were exposed to ozone for 0, 2, 4, 6, 8, 10, 12, 16, and 24 h to determine the effects of ozone on fecundity (egg laying ability) and fertility (egg hatching ability). The results showed that ozone significantly decreased fecundity and fertility in all meiotic stages except metaphase I. In Experiment II B, adult virgin Habrobracon females were exposed to Co-60 γ radiation. All treated wasps showed significant progressive decreases in fecundity and fertility with increases in radiation dose. In Experiment II C, adult virgin Habrobracon females were exposed to Co-60 γ radiation, to ozone, or to combinations thereof to determine the effects of these insults on fecundity and fertility. Together or singly ozone and radiation reduced fecundity and fertility. In Experiment III, adult virgin Habrobracon females were exposed to the conditions of Experiment II C to correlate by cytological examination of the ovarioles the effects of ionizing radiation and/or ozone on the germ cells at specific meiotic stages. Results obtained from the cytological study explain the fecundity and fertility observations

  20. Evaluating bull fertility based on non-return method

    Directory of Open Access Journals (Sweden)

    Prka Igor

    2012-01-01

    Full Text Available In order to evaluate the results of reproductive cows and heifers, different parameters of fertility are used, such as the service period, insemination index, intercalving time and others, and of the breeding bulls the values obtained through non-return. An ejaculate is taken up for further processing by veterinary centres only provided it meets the prescribed quality parameters. Rating semen parameters includes a macroscopic (volume, colour, consistency, smell and pH and a microscopic evaluation (mobility, density, percentage of live sperm and abnormal and damaged sperm. In addition to sperm quality and the fertility of the female animal, the results of the non-return method are also influenced by a number of exogenous causes (season, age, race, insemination techniques that have no small impact on the end result of insemination - pregnancy. In order to obtain more objective results of the fertility of bulls the following tasks were undertaken, namely: 1. to calculate with the non-return method the fertility of bulls in over 10,000 cows inseminated for the first time during a period of 6 years; and 2. to analyze the impact of semen quality, season, age of cow and bull, and the bull breed on the results of fertility.

  1. Genetic Compatibility Underlies Benefits of Mate Choice in an External Fertilizer.

    Science.gov (United States)

    Aguirre, J David; Blows, Mark W; Marshall, Dustin J

    2016-05-01

    Mate choice is a common feature of sexually reproducing species. In sessile or sedentary external fertilizers, however, direct interactions between reproductive partners are minimal, and instead mate recognition and choice must occur at the level of gametes. It is common for some sperm and egg combinations to have higher fertilization success than others, but it remains unclear whether differences in fertilization reflect gamete-level mate choice (GMC) for paternal quality or parental compatibility. Here, we examine the mechanisms underlying GMC in an externally fertilizing ascidian. A manipulative mate-choice assay confirmed that offspring viability was greater in clutches where we allowed GMC than in clutches where we precluded GMC. A complementary quantitative genetic experiment then revealed that paternal quality effects were generally weaker than parental compatibility effects, particularly for the trait combination underlying the benefits of GMC. Overall, our data suggest that gametes that are more compatible at fertilization produce more viable offspring than gametes that are less compatible at fertilization. Therefore, although the regalia we typically associate with sexual selection are absent in external fertilizers, mechanisms that allow females to bias fertilization in favor of some males over others produce significant fitness benefits in organisms reproducing via the ancestral strategy.

  2. Genetic parameters for female fertility, locomotion, body condition score, and linear type traits in Czech Holstein cattle

    DEFF Research Database (Denmark)

    Zink, Vojtech; Stipkova, M; Lassen, Jan

    2011-01-01

    The aim of this study was to estimate genetic parameters for fertility traits and linear type traits in the Czech Holstein dairy cattle population. Phenotypic data regarding 12 linear type traits, measured in first lactation, and 3 fertility traits, measured in each of first and second lactation,...

  3. Genetic parameters for female fertility, locomotion, body condition score, and linear type traits in Czech Holstein cattle.

    Science.gov (United States)

    Zink, V; Štípková, M; Lassen, J

    2011-10-01

    The aim of this study was to estimate genetic parameters for fertility traits and linear type traits in the Czech Holstein dairy cattle population. Phenotypic data regarding 12 linear type traits, measured in first lactation, and 3 fertility traits, measured in each of first and second lactation, were collected from 2005 to 2009 in the progeny testing program of the Czech-Moravian Breeders Corporation. The number of animals for each linear type trait was 59,467, except for locomotion, where 53,436 animals were recorded. The 3-generation pedigree file included 164,125 animals. (Co)variance components were estimated using AI-REML in a series of bivariate analyses, which were implemented via the DMU package. Fertility traits included days from calving to first service (CF1), days open (DO1), and days from first to last service (FL1) in first lactation, and days from calving to first service (CF2), days open (DO2), and days from first to last service (FL2) in second lactation. The number of animals with fertility data varied between traits and ranged from 18,915 to 58,686. All heritability estimates for reproduction traits were low, ranging from 0.02 to 0.04. Heritability estimates for linear type traits ranged from 0.03 for locomotion to 0.39 for stature. Estimated genetic correlations between fertility traits and linear type traits were generally neutral or positive, whereas genetic correlations between body condition score and CF1, DO1, FL1, CF2 and DO2 were mostly negative, with the greatest correlation between BCS and CF2 (-0.51). Genetic correlations with locomotion were greatest for CF1 and CF2 (-0.34 for both). Results of this study show that cows that are genetically extreme for angularity, stature, and body depth tend to perform poorly for fertility traits. At the same time, cows that are genetically predisposed for low body condition score or high locomotion score are generally inferior in fertility. Copyright © 2011 American Dairy Science Association

  4. Correlations in fertility across generations: can low fertility persist?

    Science.gov (United States)

    Kolk, Martin; Cownden, Daniel; Enquist, Magnus

    2014-01-01

    Correlations in family size across generations could have a major influence on human population size in the future. Empirical studies have shown that the associations between the fertility of parents and the fertility of children are substantial and growing over time. Despite their potential long-term consequences, intergenerational fertility correlations have largely been ignored by researchers. We present a model of the fertility transition as a cultural process acting on new lifestyles associated with fertility. Differences in parental and social influences on the acquisition of these lifestyles result in intergenerational correlations in fertility. We show different scenarios for future population size based on models that disregard intergenerational correlations in fertility, models with fertility correlations and a single lifestyle, and models with fertility correlations and multiple lifestyles. We show that intergenerational fertility correlations will result in an increase in fertility over time. However, present low-fertility levels may persist if the rapid introduction of new cultural lifestyles continues into the future. PMID:24478294

  5. Antenatal Diagnosis of an XXX Female

    Science.gov (United States)

    Krone, Lawrence R.; Prichard, Lorraine L.; Bradshaw, Christy L.; Jones, Oliver W.; Peterson, Raymond M.; Dixson, Barbara K.

    1975-01-01

    This report describes the first antenatal diagnosis of an XXX female. Over 150 postnatal cases of XXX females have been described. There is no specific phenotype associated with the sex chromosome abnormality and most such persons are fertile. The frequency of XXX females in mental institutions is 3.9 per 1,000 female subjects whereas the frequency in consecutive newborn infants is 1.1 per 1,000 newborns. Chi-square analysis shows this difference cannot be due to chance. On the other hand, data from consecutive newborn studies suggest that intellectual development in XXX newborns is within normal range. Available evidence favors normal development in XXX female infants although the risk for developmental disabilities may be higher for the XXX than for the XX infant. ImagesFigure 1. PMID:1154778

  6. Measuring sperm backflow following female orgasm: a new method

    Directory of Open Access Journals (Sweden)

    Robert King

    2016-10-01

    Full Text Available Background: Human female orgasm is a vexed question in the field while there is credible evidence of cryptic female choice that has many hallmarks of orgasm in other species. Our initial goal was to produce a proof of concept for allowing females to study an aspect of infertility in a home setting, specifically by aligning the study of human infertility and increased fertility with the study of other mammalian fertility. In the latter case - the realm of oxytocin-mediated sperm retention mechanisms seems to be at work in terms of ultimate function (differential sperm retention while the proximate function (rapid transport or cervical tenting remains unresolved. Method: A repeated measures design using an easily taught technique in a natural setting was used. Participants were a small (n=6, non-representative sample of females. The introduction of a sperm-simulant combined with an orgasm-producing technique using a vibrator/home massager and other easily supplied materials. Results: The sperm flowback (simulated was measured using a technique that can be used in a home setting. There was a significant difference in simulant retention between the orgasm (M=4.08, SD=0.17 and non-orgasm (M=3.30, SD=0.22 conditions; t (5=7.02, p=0.001. Cohen's d=3.97, effect size r=0.89. This indicates a medium to small effect size. Conclusions: This method could allow females to test an aspect of sexual response that has been linked to lowered fertility in a home setting with minimal training. It needs to be replicated with a larger sample size.

  7. inter-fertility among female parent clones of pineapple involved in a ...

    African Journals Online (AJOL)

    ACSS

    Ivoireconsiders fruit diversification as key component in the international pineapple industry. The objective of this study was to determine the sexual compatibility of female pineapple clones recently developed in Côte d'Ivoire. Three female hybrid clones, ...

  8. Fixation probability of a nonmutator in a large population of asexual mutators.

    Science.gov (United States)

    Jain, Kavita; James, Ananthu

    2017-11-21

    In an adapted population of mutators in which most mutations are deleterious, a nonmutator that lowers the mutation rate is under indirect selection and can sweep to fixation. Using a multitype branching process, we calculate the fixation probability of a rare nonmutator in a large population of asexual mutators. We show that when beneficial mutations are absent, the fixation probability is a nonmonotonic function of the mutation rate of the mutator: it first increases sublinearly and then decreases exponentially. We also find that beneficial mutations can enhance the fixation probability of a nonmutator. Our analysis is relevant to an understanding of recent experiments in which a reduction in the mutation rates has been observed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Sperm storage in the oviduct of the internal fertilizing frog Ascaphus truei.

    Science.gov (United States)

    Sever, D M; Moriarty, E C; Rania, L C; Hamlett, W C

    2001-04-01

    This study provides the first descriptions of sperm storage at the tissue and cellular levels in a female frog or toad. Oviducal anatomy was studied by light and electron microscopy in Ascaphus truei from north coastal California. Ascaphus truei is one of the few species of anurans in which fertilization is internal. Unlike other anurans with internal fertilization, however, mating in A. truei consists of a unique combination of amplectic and copulatory mechanisms that we term "copulexus." Posterior to a short, aglandular infundibular region, the oviduct possesses: 1) a proximal, convoluted ampullary region where intrinsic tubular glands secrete gelatinous envelopes around eggs; 2) a middle ovisac region where fertilization occurs; and 3) a distal oviducal sinus formed by medial junction of the ovisacs. Sperm storage tubules (SSTs) occur in the anterior portions of the ovisacs and consist of simple tubular glands. SSTs and the rest of the oviducal lining stain positively with the periodic acid-Schiff's procedure for neutral carbohydrates and this reaction is especially intense in reproductively active females. Sperm were found in the SSTs of gravid females as well as some nonvitellogenic females. The sperm are in orderly bundles in the SSTs, and although occasionally sperm nuclei were embedded in the epithelium, no evidence for spermiophagy was found. Oviducal sperm storage in A. truei is homoplastic, with closest structural similarities to squamate reptiles. Oviduct/sperm design constraints appear to limit the options for expression of features associated with oviducal sperm storage. Copyright 2001 Wiley-Liss, Inc.

  10. Role of oxidative stress in female reproduction

    Directory of Open Access Journals (Sweden)

    Sharma Rakesh K

    2005-07-01

    Full Text Available Abstract In a healthy body, ROS (reactive oxygen species and antioxidants remain in balance. When the balance is disrupted towards an overabundance of ROS, oxidative stress (OS occurs. OS influences the entire reproductive lifespan of a woman and even thereafter (i.e. menopause. OS results from an imbalance between prooxidants (free radical species and the body's scavenging ability (antioxidants. ROS are a double-edged sword – they serve as key signal molecules in physiological processes but also have a role in pathological processes involving the female reproductive tract. ROS affect multiple physiological processes from oocyte maturation to fertilization, embryo development and pregnancy. It has been suggested that OS modulates the age-related decline in fertility. It plays a role during pregnancy and normal parturition and in initiation of preterm labor. Most ovarian cancers appear in the surface epithelium, and repetitive ovulation has been thought to be a causative factor. Ovulation-induced oxidative base damage and damage to DNA of the ovarian epithelium can be prevented by antioxidants. There is growing literature on the effects of OS in female reproduction with involvement in the pathophsiology of preeclampsia, hydatidiform mole, free radical-induced birth defects and other situations such as abortions. Numerous studies have shown that OS plays a role in the pathoysiology of infertility and assisted fertility. There is some evidence of its role in endometriosis, tubal and peritoneal factor infertility and unexplained infertility. This article reviews the role OS plays in normal cycling ovaries, follicular development and cyclical endometrial changes. It also discusses OS-related female infertility and how it influences the outcomes of assisted reproductive techniques. The review comprehensively explores the literature for evidence of the role of oxidative stress in conditions such as abortions, preeclampsia, hydatidiform mole, fetal

  11. Morphology offers no clues to asexual vs. sexual origin of small Acropora cervicornis (Scleractinia: Acroporidae colonies

    Directory of Open Access Journals (Sweden)

    D. E Williams

    2006-12-01

    Full Text Available Sexual recruitment of the staghorn coral, Acropora cervicornis, is accepted to be very rare. Instead, these branching corals proliferate through fragmentation leading to dense mono-specific and possibly monoclonal stands. For acroporid corals, which have suffered drastic population declines, dominance of asexual reproduction results in low levels of genotypic diversity and limited ability to re-colonize extirpated areas. Small colonies with a single encrusting, symmetrical base, and few incipient branches are frequently presumed to be the result of a settled planula (i.e. sexual reproduction. Here, we show that colonies fitting this description (i.e., presumed sexual recruits can result from asexual fragmentation. Acropora cervicornis colonies (~20 cm diameter were tagged and observed over eighteen months. In several cases, colony offshoots fused with the adjacent substrate forming secondary disc-like attachment points. Following natural fragmentation, these discs of tissue became separated from the original colony, and were observed to heal and give rise to smaller colonies with striking similarity to the expected morphology of a sexual recruit. Thus, presuming a colony is a sexual recruit based on appearance is unreliable and may lead to inflated expectations of genetic diversity among populations. The accurate assessment of recruitment and genetic diversity is crucial to predicting the recovery potential of these imperiled and ecologically irreplaceable reef corals. Rev. Biol. Trop. 54 (Suppl. 3: 145-151. Epub 2007 Jan. 15.Se ha aceptado que el reclutamiento sexual del coral asta de venado, Acropora cervicornis, es muy raro. Por el contrario, estos corales ramificados proliferan a través de fragmentación, generando densas bases monoespecíficas e incluso monoclonales. Para corales acropóridos, los cuales han sufrido disminuciones de población drásticas, la dominancia de reproducción asexual resulta en bajos niveles de diversidad genot

  12. Preconception care: The influence of nutrition and lifestyle on fertility

    NARCIS (Netherlands)

    F. Hammiche (Fatima)

    2012-01-01

    textabstractIn Western societies there has been a change in reproductive behaviour with a tendency towards more couples postponing childbearing. As a consequence the number of couples experiencing impaired fertility in the Netherlands is rising. Female age in this respect is the commonly studied

  13. Albania: Trends and patterns, proximate determinants and policies of fertility change

    Directory of Open Access Journals (Sweden)

    Letizia Mencarini

    2008-07-01

    Full Text Available For a very long time, Albania has had one of the highest levels of fertility in Europe: in 2002 the total fertility rate of 2.2 children per woman was the highest in Europe. Although this current level is high, the country has experienced a rapid fertility reduction during the last 50 years: a TFR decline from 7 to 2.2. This reduction has occurred in the absence of modern contraception and abortion, which indicates the significance of investments in the social agenda during the communist regime that produced policies with indirect effects on fertility. Most significant of these were policies focused on education, in particular on female education. Social and demographic settings for a further fertility reduction in Albania have been present since 1990. Contraception and abortion have been legalized and available since the early 1990s, but knowledge of their use is still not widespread in the country, largely due to the interplay between traditional and modern norms of Albanian society. This chapter points out that future fertility levels will be determined not only by new policies that might be introduced, but predominantly by the balance of this interplay.

  14. Method of Euthanasia Influences the Oocyte Fertilization Rate with Fresh Mouse Sperm

    Science.gov (United States)

    Hazzard, Karen C; Watkins-Chow, Dawn E; Garrett, Lisa J

    2014-01-01

    In vitro fertilization (IVF) is used to produce mouse embryos for a variety of reasons. We evaluated the effect of the method of euthanasia on the fertilization rate in 2 different IVF protocols. Oocytes collected from C57BL/6J female mice euthanized by CO2 inhalation or cervical dislocation were used in IVF with fresh sperm from either wild-type or genetically engineered C57BL/6J. Compared with CO2 inhalation, cervical dislocation improved the resulting rate of fertilization by 18% in an IVF method using Cook media and by 13% in an IVF method using methyl-B cyclodextrin and reduced glutathione. The lower fertilization rate due to euthanasia by CO2 inhalation was accompanied by changes in blood pH and body temperature despite efforts to minimize temperature drops. In our hands, euthanasia by cervical dislocation improved fertilization rates and consequently reduced the number of egg-donor mice required. PMID:25650969

  15. Method of euthanasia influences the oocyte fertilization rate with fresh mouse sperm.

    Science.gov (United States)

    Hazzard, Karen C; Watkins-Chow, Dawn E; Garrett, Lisa J

    2014-11-01

    In vitro fertilization (IVF) is used to produce mouse embryos for a variety of reasons. We evaluated the effect of the method of euthanasia on the fertilization rate in 2 different IVF protocols. Oocytes collected from C57BL/6J female mice euthanized by CO2 inhalation or cervical dislocation were used in IVF with fresh sperm from either wild-type or genetically engineered C57BL/6J. Compared with CO2 inhalation, cervical dislocation improved the resulting rate of fertilization by 18% in an IVF method using Cook media and by 13% in an IVF method using methyl-B cyclodextrin and reduced glutathione. The lower fertilization rate due to euthanasia by CO2 inhalation was accompanied by changes in blood pH and body temperature despite efforts to minimize temperature drops. In our hands, euthanasia by cervical dislocation improved fertilization rates and consequently reduced the number of egg-donor mice required.

  16. Emergency IVF for embryo freezing to preserve female fertility: a French multicentre cohort study.

    Science.gov (United States)

    Courbiere, B; Decanter, C; Bringer-Deutsch, S; Rives, N; Mirallié, S; Pech, J C; De Ziegler, D; Carré-Pigeon, F; May-Panloup, P; Sifer, C; Amice, V; Schweitzer, T; Porcu-Buisson, G; Poirot, C

    2013-09-01

    What are the outcomes of French emergency IVF procedures involving embryo freezing for fertility preservation before gonadotoxic treatment? Pregnancy rates after emergency IVF, cryopreservation of embryos, storage, thawing and embryo transfer (embryo transfer), in the specific context of the preservation of female fertility, seem to be similar to those reported for infertile couples undergoing ART. A French retrospective multicentre cohort study initiated by the GRECOT network-the French Study Group for Ovarian and Testicular Cryopreservation. We sent an e-mail survey to the 97 French centres performing the assisted reproduction technique in 2011, asking whether the centre performed emergency IVF and requesting information about the patients' characteristics, indications, IVF cycles and laboratory and follow-up data. The response rate was 53.6% (52/97). Fourteen French centres reported that they performed emergency IVF (56 cycles in total) before gonadotoxic treatment, between 1999 and July 2011, in 52 patients. The patients had a mean age of 28.9 ± 4.3 years, and a median length of relationship of 3 years (1 month-15 years). Emergency IVF was indicated for haematological cancer (42%), brain tumour (23%), sarcoma (3.8%), mesothelioma (n = 1) and bowel cancer (n = 1). Gynaecological problems accounted for 17% of indications. In 7.7% of cases, emergency IVF was performed for autoimmune diseases. Among the 52 patients concerned, 28% (n = 14) had undergone previous courses of chemotherapy before beginning controlled ovarian stimulation (COS). The initiation of gonadotoxic treatment had to be delayed in 34% of the patients (n = 19). In total, 56 cycles were initiated. The mean duration of stimulation was 11.2 ± 2.5 days, with a mean peak estradiol concentration on the day on which ovulation was triggered of 1640 ± 1028 pg/ml. Three cycles were cancelled due to ovarian hyperstimulation syndrome (n = 1), poor response (n = 1) and treatment error (n = 1). A mean of 8

  17. Sexual and asexual reproduction in Didemnum rodriguesi (Ascidiacea, Didemnidae Reprodução sexuada e assexuada em Didemnum rodriguesi (Ascidiacea, Didemnidae

    Directory of Open Access Journals (Sweden)

    Nicole F. Ritzmann

    2009-03-01

    Full Text Available Sexual and asexual reproduction and associated population dynamics were investigated in the colonial ascidian Didemnum rodriguesi Rocha & Monniot, 1993 (Didemnidae in southern Brazil. Investment in sexual (production of new individuals and asexual (colony growth reproduction was compared between seasons. Permanently marked quadrats were repeatedly photographed to measure changes in colonies. Eggs and larvae were counted monthly in collected colonies. This species alternates seasonally between sexual (summer and asexual (winter reproduction. In summer, colonies were smaller, brooded eggs and larvae and recruitment rates were greater, while in winter, colony size was larger and eggs and larvae were absent. There is a relationship between fecundity and colony area. Fragmentation and fusion of colonies were similar in summer and winter, as well as mortality. In conclusion, D. rodriguesi has a lifecycle usual for high latitude ascidians with a limited time length for sexual reproduction and alternate investment in sexual and asexual reproduction along the year.Reprodução sexuada e assexuada, mortalidade e a dinâmica de fusões e fissões de colônias de Didemnum rodriguesi Rocha & Monniot, 1993 foram investigados e comparados no sul do Brasil, no inverno e verão. Tais eventos foram analisados por fotografias de áreas permanentemente demarcadas e coletas mensais de colônias. Os resultados indicam que esta espécie alterna sazonalmente a reprodução sexuada (verão e assexuada (inverno. Durante o verão as colônias são mais abundantes e menores, com ovos e larvas incubados e taxas de recrutamento maiores. No inverno há um menor número de colônias, porém de maior tamanho e inférteis. Existe uma relação entre fecundidade e tamanho da colônia. Não foram encontradas diferenças estatísticas no número de eventos de fragmentação e fusão entre o verão e inverno, bem como para mortalidade. Conclui-se que esta espécie tem um ciclo de

  18. A Study On Correlation Between Fertility And Contraceptive Prevalence In Rural Community

    Directory of Open Access Journals (Sweden)

    Reema Verma

    2004-06-01

    Full Text Available Objectives: (1    To find the contraceptive prevalence in different reproductive age group females. (2    What is the correlation between fertility pattern and contraceptive prevalence. Study Design : Cross sectional descriptive study. Setting : Community Development block Sarojini Nagar, Lucknow district. Study universe : Married females in reproductive age group (15-49 Years. Study variables : Age, fertility, contraceptive prevalence, education and social class. Statistical analysis : Chi Square test. Result : Contraceptive prevalence was 29.7%. It was 6.5% for women aged 15-19 year to 45.2% for women aged 35­39 years. The acceptors were analyzed based on the number of living children. 74% of the acceptors had 3 or more children as against 26% with 0 to 2 living children.

  19. Dynamic Formation of Asexual Diploid and Polyploid Lineages: Multilocus Analysis of Cobitis Reveals the Mechanisms Maintaining the Diversity of Clones

    Czech Academy of Sciences Publication Activity Database

    Janko, Karel; Kotusz, J.; de Gelas, K.; Šlechtová, Věra; Opoldusová, Zuzana; Drozd, P.; Choleva, Lukáš; Popiolek, M.; Baláž, M.

    2012-01-01

    Roč. 7, č. 9 (2012), s. 1-14 E-ISSN 1932-6203 R&D Projects: GA ČR GA206/09/1298 Grant - others:University of Wroclav(PL) 10/19/S/MP Institutional research plan: CEZ:AV0Z50450515 Keywords : asexual lineages Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.730, year: 2012

  20. Fertility knowledge and intentions to have children in a national study of Australian secondary school students.

    Science.gov (United States)

    Heywood, Wendy; Pitts, Marian K; Patrick, Kent; Mitchell, Anne

    2016-10-01

    This paper reports on fertility knowledge and intentions to have children among a national sample of students in years 10-12. Data were from the Fifth National Survey of Australian Secondary Students and Sexual Health. Students identified factors that could affect fertility, if they wanted children and at what age. Most students wanted to have children (77%). Of those who wanted children or were unsure (n=1,780), 54% were able to identify six of eight factors that could affect fertility. Male students had poorer knowledge than females. Poorer knowledge was also reported by male students who were born overseas or used marijuana and by female students who were sexually active or religious. More than half the students (59%) wanted their first child aged 25-29, while 19% wanted their first child after 30. Intentions to have children at an earlier age were associated with being religious, sexually active (females), and using marijuana (males). Students not exclusively attracted to the opposite sex were more likely to want children at an older age. Most students typically want children in their late 20s. Many were unaware of factors that could affect their fertility and there was a mismatch between intentions and likely behaviour. These factors could be addressed as part of relationship education. © 2016 Public Health Association of Australia.

  1. Meiotic genes and sexual reproduction in the green algal class Trebouxiophyceae (Chlorophyta)

    KAUST Repository

    Fučíková, Karolina

    2015-04-06

    © 2015 Phycological Society of America. Sexual reproduction is widespread in eukaryotes and is well documented in chlorophytan green algae. In this lineage, however, the Trebouxiophyceae represent a striking exception: in contrast to its relatives Chlorophyceae and Ulvophyceae this group appears to be mostly asexual, as fertilization has been rarely observed. Assessments of sexual reproduction in the Trebouxiophyceae have been based on microscopic observation of gametes fusing. New genomic data offer now the opportunity to check for the presence of meiotic genes, which represent an indirect evidence of a sexual life cycle. Using genomic and transcriptomic data for 12 taxa spanning the phylogenetic breadth of the class, we tried to clarify whether genuine asexuality or cryptic sexuality is the most likely case for the numerous putatively asexual trebouxiophytes. On the basis of these data and a bibliographic review, we conclude that the view of trebouxiophytes as primarily asexual is incorrect. In contrast to the limited number of reports of fertilization, meiotic genes were found in all genomes and transcriptomes examined, even in species presumed asexual. In the taxa examined the totality or majority of the genes were present, Helicosporidium and Auxenochlorella being the only partial exceptions (only four genes present). The evidence of sex provided by the meiotic genes is phylogenetically widespread in the class and indicates that sexual reproduction is not associated with any particular morphological or ecological trait. On the basis of the results, we expect that the existence of the meiotic genes will be documented in all trebouxiophycean genomes that will become available in the future.

  2. Nutrition-dependent fertility response to juvenile hormone in non-social Euodynerus foraminatus wasps and the evolutionary origin of sociality.

    Science.gov (United States)

    Tibbetts, Elizabeth A; Mettler, Alexander; Donajkowski, Kellie

    2013-03-01

    The reproductive ground plan hypothesis (RGPH) proposes that the ovarian cycle in solitary insects provides the basis for social evolution, so similar mechanisms are predicted to influence reproductive plasticity in social and solitary species. Specifically, reproductive plasticity in social species originated via modification of nutrition-dependent fertility response to juvenile hormone (JH) in solitary insects. Testing this prediction requires information about the factors that influence fertility in non-social relatives of the eusocial hymenoptera. However, no previous studies have examined how JH or nutritional condition influence fertility in Eumenines, the non-social group most closely related to social wasps. Here, we find support for the RGPH, as JH increases Euodynerus foraminatus fertility. Fertility is also condition-dependent, as heavy E. foraminatus are more fertile than light E. foraminatus. In addition, we measure the factors associated with mating success in E. foraminatus, finding that multiple factors influence mating success, including male weight, male mating experience, and female age. There is also higher variance in male than female reproductive success, suggesting that males may experience substantial sexual selection in this species. Overall, the relationships between JH, body weight, and fertility in E. foraminatus support the RGPH for the origin of sociality by demonstrating that there are strong parallels in the mechanisms that mediate fertility of social and non-social wasps. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. The fertility of recent migrants to England and Wales

    Directory of Open Access Journals (Sweden)

    James Robards

    2016-06-01

    Full Text Available Background: Estimates of fertility for the overseas-born based on the period Total Fertility Rate (TFR suggest that levels of childbearing are significantly higher among foreign-born women than women born in the UK. However, migration and timing of subsequent family formation mean that aggregate measures of fertility based on period TFRs may not be a useful indicator of the likely completed family size that migrant women will have at the end of their reproductive lives. Objective: The paper quantifies childbearing according to duration since migration among female migrants to England and Wales arriving between 2001 and 2011, and examines how these patterns differ according to age at arrival and country of birth. Methods: Data from the Office for National Statistics Longitudinal Study, a 1Š sample of the population of England and Wales, are used to identify the reported date of arrival in the UK and to estimate childbearing prior to and subsequent to arrival. Results: Fertility rates peak in the first one to four years subsequent to arrival among migrants from Pakistan and Bangladesh. Migrants from India and Poland show a delay in childbearing after migration to England and Wales, and lower fertility rates compared to migrants from Pakistan and Bangladesh, who show high fertility after migration at least for the first five years. Conclusions: There are large differences in the timing of fertility among migrants according to age at arrival and migrant country of origin, which are likely to be related to the reason for migration. Tempo distortions among some migrant groups mean that the period TFR is not necessarily a useful summary measure of the likely lifetime fertility of migrant groups.

  4. Male-fertility-restorer mutation induced by x-rays in wheat

    International Nuclear Information System (INIS)

    Sasaki, Mutsuo; Nakata, Noboru; Yasumuro, Yoshimasa

    1982-01-01

    Some male-fertility restoring mutants were obtained by X-irradiation (20 or 25 kR, 105.3 R/min) of the air-dried seed of cytoplasmic male-sterile (cms) wheat, (timopheevi)-Bison. These X-ray induced male-fertility restoring mutant (Rfx) lines restored the male fertility of F 1 hybrids with cms (timopheevi)-Bison as female, but their fertility-restoring ability was not superior to that of known restorers such as Gironde, Primepi, and (t)-H30. The Rfx lines were also different from the original (timopheevi)-Bison, in many characters. The study on these multicharacter mutations with 18 morphological and physiological characters of the 7 M 6 line groups derived from the 7M 2 plants, revealed that each M 2 progenitor plant of each M 6 line-group had the mutant genes for almost all these characters, and that the mutation for at least half of all these mutant genes was induced in the original cell of the gamates of each X-irradiated M 1 plant. Considering the multicharacter mutations of the Rfx lines, a backcross method for the mutation breeding of male-fertility restorers in wheat was proposed. (Kaihara, S.)

  5. Reproductive hormones disorders of Sudanese females using immunoradiometric assay (IRMA)

    International Nuclear Information System (INIS)

    Ali, N. I.; Almahi, W. A. A.; Abdalla, O. M.; Bafarag, S. M. I.; Abdelgadir, O. M.; Eltayeb, M. A. H.; Hassan, A. M. E.; Hassan, A. M. E.

    2004-12-01

    In this study fertility hormones were measured for 587 infertile Sudanese female referred from gynecological clinics. The ages of these female ranges from 16-50 years divided into seven groups. Eighty seven percent of them are in the age range between 21 and 40 year which correlate with the female's fertile period and 5.6% of them under 20 years. Sensitive (IRMA) method was used for measuring the hormone concentration. The objective of this study was to found out the percentage of hormonal disorders and its relation to the age in infertile Sudanese females. The age group (21-25) was the most affected group by the Poly Cystic Ovary Syndrome (PCOS) and represented 5.1% of the total number of patients. The least group was the age group (41-45) with a percentage of 0.4. The LH and the FSH in the age group of (31-35) was found to be higher than the other groups and represented 11.4% and 7.8% from the total number of patients respectively. The least percent of high level of LH and FSH was found to be in the most fertile age group (15-20) and it was 1.7% and 1.0% from the total number of studied patient, respectively. Those who were in the age range (26-30) with hyperprolactinaemia represented 10.4% of patients, while those with age rang (46-50) with hyperprolactinaemia represented the lowest percentage (1.2%). The percentage of patients having high LH and high FSH was 44.5% and 29.1% respectively, while the hyperprolactinaemia among the infertile Sudanese female was found to 38.2%.(Author)

  6. CONTRIBUTIONS OF SEXUAL AND ASEXUAL REPRODUCTION TO POPULATION STRUCTURE IN THE CLONAL SOFT CORAL, ALCYONIUM RUDYI.

    Science.gov (United States)

    McFadden, Catherine S

    1997-02-01

    Numerous studies of population structure in sessile clonal marine invertebrates have demonstrated low genotypic diversity and nonequilibrium genotype frequencies within local populations that are monopolized by relatively few, highly replicated genets. All of the species studied to date produce planktonic sexual propagules capable of dispersing long distances; despite local genotypic disequilibria, populations are often panmictic over large geographic areas. The population structure paradigm these species represent may not be typical of the majority of clonal invertebrate groups, however, which are believed to produce highly philopatric sexual propagules. I used allozyme variation to examine the population structure of the temperate soft coral, Alcyonium rudyi, a typical clonal species whose sexually produced larvae and asexually produced ramets both have very low dispersal capabilities. Like other clonal plants and invertebrates, the local population dynamics of A. rudyi are dominated by asexual reproduction, and recruitment of new sexually produced genets occurs infrequently. As expected from its philopatric larval stage, estimates of genetic differentiation among populations of A. rudyi were highly significant at all spatial scales examined (mean θ = 0.300 among 20 populations spanning a 1100-km range), suggesting that genetic exchange seldom occurs among populations separated by as little as a few hundred meters. Mapping of multilocus allozyme genotypes within a dense aggregation of A. rudyi ramets confirmed that dispersal of asexual propagules is also very limited: members of the same genet usually remain within invertebrates, populations of A. rudyi do not appear to be dominated by a few widespread genets: estimates of genotypic diversity (G o ) within 20 geographically distinct populations did not differ from expectations for outcrossing, sexual populations. Despite theoretical suggestions that philopatric dispersal combined with typically small effective

  7. Fertility-related knowledge and reproductive goals in childhood cancer survivors: short communication.

    Science.gov (United States)

    Lehmann, V; Keim, M C; Nahata, L; Shultz, E L; Klosky, J L; Tuinman, M A; Gerhardt, C A

    2017-11-01

    Do young adult survivors of childhood cancer know their fertility status, in the context of their parenthood goals and screening for gonadal functioning? While 80% of survivors (who were without children) wanted children in the future, most did not know their fertility status, and screening for gonadal functioning was underutilized. Survivors of childhood cancer are at risk for infertility, but fertility counseling and assessment are underutilized. Separate studies indicated that survivors' fertility-related knowledge is poor and that they often wanted to have children. Yet, studies have not investigated the intersection of both issues, as well as potential distress if parenthood goals are not met. Young adult male and female survivors of childhood cancer (N = 149) completed cross-sectional surveys, and data for those without children (n = 105, 70.5%) are presented here. Participants were 20-40 years old (M = 26.5), diagnosed 5-33 years prior to study participation, and completed questionnaires online. Knowledge of fertility status, parenthood goals, and potential distress if survivors were unable to have children were assessed. Medical records were reviewed for hormone levels as indicators of screening for gonadal functioning. Most survivors (n = 81; 77.1%) did not know their fertility status, while over 80% (n = 89) wanted children (neither aspect varied by socio-demographic/cancer-specific factors). Two-thirds of survivors indicated they would be distressed if parenthood goals remained unfulfilled; especially female (versus male, t = 2.64; P = 0.01) or partnered (versus single, t = -3.45; P fertility status. Relevant risk factors may have not been identified owing to limited sample size and missing treatment information. The underutilization of screening for gonadal functioning needs further exploration in other pediatric centers. Most adult childhood cancer survivors want to become parents, but do not know their fertility status, which could cause significant

  8. FvSTR1, a striatin orthologue in Fusarium virguliforme, is required for asexual development and virulence.

    Science.gov (United States)

    Islam, Kazi T; Bond, Jason P; Fakhoury, Ahmad M

    2017-08-01

    The soil-borne fungus Fusarium virguliforme causes sudden death syndrome (SDS), one of the most devastating diseases of soybean in North and South America. Despite the importance of SDS, a clear understanding of the fungal pathogenicity factors that affect the development of this disease is still lacking. We have identified FvSTR1, a F. virguliforme gene, which encodes a protein similar to a family of striatin proteins previously reported to regulate signalling pathways, cell differentiation, conidiation, sexual development, and virulence in filamentous fungi. Striatins are multi-domain proteins that serve as scaffolding units in the striatin-interacting phosphatase and kinase (STRIPAK) complex in fungi and animals. To address the function of a striatin homologue in F. virguliforme, FvSTR1 was disrupted and functionally characterized using a gene knock out strategy. The resulting Fvstr1 mutants were largely impaired in conidiation and pigmentation, and displayed defective conidia and conidiophore morphology compared to the wild-type and ectopic transformants. Greenhouse virulence assays revealed that the disruption of FvSTR1 resulted in complete loss of virulence in F. virguliforme. Microtome studies using fluorescence microscopy showed that the Fvstr1 mutants were defective in their ability to colonize the vascular system. The Fvstr1 mutants also showed a reduced transcript level of genes involved in asexual reproduction and in the production of secondary metabolites. These results suggest that FvSTR1 has a critical role in asexual development and virulence in F. virguliforme.

  9. Female in-nest chatter song increases predation.

    Science.gov (United States)

    Kleindorfer, Sonia; Evans, Christine; Mahr, Katharina

    2016-01-01

    Female song is an ancestral trait in songbirds, yet extant females generally sing less than males. Here, we examine sex differences in the predation cost of singing behaviour. The superb fairy-wren (Malurus cyaneus) is a Southern Hemisphere songbird; males and females provision the brood and produce solo song year-round. Both sexes had higher song rate during the fertile period and lower song rate during incubation and chick feeding. Females were more likely than males to sing close to or inside the nest. For this reason, female but not male song rate predicted egg and nestling predation. This study identifies a high fitness cost of song when a parent bird attends offspring inside a nest and explains gender differences in singing when there are gender differences in parental care. © 2016 The Author(s).

  10. Sex in an uncertain world: environmental stochasticity helps restore competitive balance between sexually and asexually reproducing populations.

    Science.gov (United States)

    Park, A W; Vandekerkhove, J; Michalakis, Y

    2014-08-01

    Like many organisms, individuals of the freshwater ostracod species Eucypris virens exhibit either obligate sexual or asexual reproductive modes. Both types of individual routinely co-occur, including in the same temporary freshwater pond (their natural habitat in which they undergo seasonal diapause). Given the well-known two-fold cost of sex, this begs the question of how sexually reproducing individuals are able to coexist with their asexual counterparts in spite of such overwhelming costs. Environmental stochasticity in the form of 'false dawn' inundations (where the first hydration is ephemeral and causes loss of early hatching individuals) may provide an advantage to the sexual subpopulation, which shows greater variation in hatching times following inundation. We explore the potential role of environmental stochasticity in this system using life-history data analysis, climate data, and matrix projection models. In the absence of environmental stochasticity, the population growth rate is significantly lower in sexual subpopulations. Climate data reveal that 'false dawn' inundations are common. Using matrix projection modelling with and without environmental stochasticity, we demonstrate that this phenomenon can restore appreciable balance to the system, in terms of population growth rates. This provides support for the role of environmental stochasticity in helping to explain the maintenance of sex and the occurrence of geographical parthenogenesis. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

  11. A Nutrition Screening Form for Female Infertility Patients.

    Science.gov (United States)

    Langley, Susie

    2014-12-01

    A Nutrition Screening Form (NSF) was designed to identify lifestyle risk factors that negatively impact fertility and to provide a descriptive profile of 300 female infertility patients in a private urban infertility clinic. The NSF was mailed to all new patients prior to the initial physician's visit and self-reported data were assessed using specific criteria to determine if a nutrition referral was warranted. This observational study revealed that 43% of the women had a body mass index (BMI) nutrition-related lifestyle factors that may negatively impact fertility and identified weight, BMI, diet, exercise, and stress as modifiable risk factors deserving future research. NSF information can help increase awareness among health professionals and patients about the important link between nutrition, fertility, and successful reproductive outcomes.

  12. The acceptability of stem cell-based fertility treatments for different indications

    NARCIS (Netherlands)

    Hendriks, S.; Dancet, E. A. F.; Vliegenthart, R.; Repping, S.

    2017-01-01

    STUDY QUESTION: What is the acceptability of using stem cell-based fertility treatments (SCFT) for different indications according to gynaecologists and the general public? SUMMARY ANSWER: The majority of gynaecologists and the general public accept SCFT for the indications female or male

  13. Germ cell toxicity: significance in genetic and fertility effects of radiation and chemicals

    International Nuclear Information System (INIS)

    Oakberg, E.F.

    1983-01-01

    The response of the male and female to radiation and chemicals is different. Any loss of oocytes in the female cannot be replaced, and if severe enough, will result in a shortening of the reproductive span. In the male, a temporary sterile period may be induced owing to destruction of the differentiating spermatogonia, but the stem cells are the most resistant spermatogonial type, are capable of repopulating the seminiferous epithelium, and fertility usually returns. The response of both the male and female changes with development of the embryonic to the adult gonad, and with differentiation and maturation in the adult. The primordial germ cells, early oocytes, and differentiating spermatogonia of the adult male are unusually sensitive to the cytotoxic action of noxious agents, but each agent elicits a specific response owing to the intricate biochemical and physiological changes associated with development and maturation of the gametes. The relationship of germ cell killing to fertility is direct, and long-term fertility effects can be predicted from histological analysis of the gonads. The relationship to genetic effects, on the other hand, is indirect, and acts primarily by limiting the cell stages available for testing, by affecting the distribution of mitotically active stem cells among the different stages of the mitotic cycle, and thereby, changing both the type and frequency of genetic effects observed. 100 references, 38 figures, 7 tables

  14. Too old to have children? Lessons from natural fertility populations

    NARCIS (Netherlands)

    Eijkermans, M.J.C.; van Poppel, F.W.A.; Habbema, J.D.F.; Smith, K.R.; Leridon, H.; te Velde, E.R.

    2014-01-01

    study question: Is it possible to construct an age curve denoting the ages above which women are biologically too old to reproduce? summaryanswer:We constructed a curve based on the distribution of female age at last birth in natural fertility populations reflecting the ages above which women have

  15. Sex differences in obesity associated with total fertility rate.

    Directory of Open Access Journals (Sweden)

    Robert Brooks

    Full Text Available The identification of biological and ecological factors that contribute to obesity may help in combating the spreading obesity crisis. Sex differences in obesity rates are particularly poorly understood. Here we show that the strong female bias in obesity in many countries is associated with high total fertility rate, which is well known to be correlated with factors such as low average income, infant mortality and female education. We also document effects of reduced access to contraception and increased inequality of income among households on obesity rates. These results are consistent with studies that implicate reproduction as a risk factor for obesity in women and that suggest the effects of reproduction interact with socioeconomic and educational factors. We discuss our results in the light of recent research in dietary ecology and the suggestion that insulin resistance during pregnancy is due to historic adaptation to protect the developing foetus during famine. Increased access to contraception and education in countries with high total fertility rate might have the additional benefit of reducing the rates of obesity in women.

  16. Inbreeding, heterosis, fertility, plasmon differentiation and Phytophthora resistance in Solanum verrucosum Schlechtd., and some interspecific crosses in Solanum

    NARCIS (Netherlands)

    Abdalla, M.M.F.

    1970-01-01

    Solanum verrucosum (2n = 24) is a self-compatible, highly fertile species. This conclusion is drawn from the results of studies on 21 various introductions of this species. In spite of self-compatibility and good male and female fertility, the species generally needs a pollinating agent to

  17. Nano Fertilizers

    Directory of Open Access Journals (Sweden)

    Hatice DAĞHAN

    2017-06-01

    Full Text Available Agricultural land is decreasing day by day due to erosion, environmental pollution, unconscious irrigation and fertilization. On the other hand, it is necessary to increase agricultural production in order to meet the needs of the developing industry as well as the nutritional needs of the growing population. In the recent years, nano fertilizers have begun to be produced to obtain the highest amount and quality of production from the unit area. Previous research shows that nano fertilizers cause an increase in the use efficiency of plant nutrients, reduce soil toxicity, minimize the potential adverse effects of excessive chemical fertilizer use, and reduce fertilizer application frequency. Nano fertilizers are important in agriculture to increase crop yield and nutrient use efficiency, and to reduce excessive use ofchemical fertilizers. The most important properties of these fertilizers are that they contain one or more of macro and micronutrients, they can be applied frequently in small amounts and are environmentally friendly. However, when applied at high doses, they exhibit decreasing effects on plant growth and crop yields, similar to chemical fertilizers. In this review, the definition, importan ce, and classification of nano fertilizers, their application in plant production, advantages and disadvantages and the results obtained in this field were discussed.

  18. Improving patient-centredness in partnership with female patients: a cluster RCT in fertility care

    NARCIS (Netherlands)

    Huppelschoten, A.G.; Nelen, W.L.D.M.; Westert, G.P.; Golde, R.J.T. van; Adang, E.M.M.; Kremer, J.A.M.

    2015-01-01

    QUESTION: What is the effect of a multifaceted intervention with participation of patients on improvement of patient-centredness in fertility care? SUMMARY ANSWER: A multifaceted intervention with participation of patients did not improve total patient-centredness scores provided by women in

  19. Fertility rates and perinatal outcomes of adolescent pregnancies: a retrospective population-based study

    OpenAIRE

    Souza, Maria de Lourdes de; Lynn, Fiona Ann; Johnston, Linda; Tavares, Eduardo Cardoso Teixeira; Brüggemann, Odaléa Maria; Botelho, Lúcio José

    2017-01-01

    ABSTRACT Objective: analyze trends in fertility rates and associations with perinatal outcomes for adolescents in Santa Catarina, Brazil. Methods: a population-based study covering 2006 to 2013 was carried out to evaluate associations between perinatal outcomes and age groups, using odds ratios, and Chi-squared tests. Results: differences in the fertility rate among female adolescents across regions and time period were observed, ranging from 40.9 to 72.0 per 1,000 in mothers aged 15-19 ye...

  20. New Reproductive Assemblages: Understanding, Managing and ‘Using’ Human In Vitro Fertilization (IVF)

    OpenAIRE

    Just, E.M.

    2009-01-01

    This dissertation is a contribution to the ongoing discussion about the body and in vitro fertilization (IVF), also known as assisted reproduction or technologically enhanced reproduction. With help of empirical research on Dutch and Polish IVF-couples, Edyta Just puts into question the meaning of IVF and discusses the best way of managing the phenomenon and to use it to transform existing ideologies, norms, convictions en discussions on matters such as reproduction, (in)fertility, female/mal...

  1. A Gene Expressed during Sexual and Asexual Sporulation in Phytophthora infestans is a Member of the Puf Family of Translational Regulators

    DEFF Research Database (Denmark)

    Cvitanich, Cristina; Judelson, Howard S.

    2003-01-01

    and persisted in mature oospores. Expression was also observed in hyphal tips just prior to asexual sporulation, in sporangiophores, in mature sporangia, and in zoospores. The signal quickly disappeared once spores made the transition to hyphae after germination. Nutrient limitation did not induce the gene...

  2. Innovative fertility preservation strategies and programs for young adults with cancer

    Directory of Open Access Journals (Sweden)

    Johnson RH

    2016-01-01

    Full Text Available Rebecca H Johnson Division of Pediatric Hematology/Oncology, Department of Pediatrics, Mary Bridge Hospital, MultiCare Health System, Tacoma, WA, USA Abstract: Preservation of fertility is a key issue for young adults newly diagnosed with cancer. Up to 90% of cancer patients under the age of 45 are at risk for fertility impairment following cancer therapy. Cancer patients who are not offered fertility preservation (FP and those who become infertile following therapy may experience long-term psychosocial distress. This review summarizes the numerous effective strategies for preserving fertility, including sperm banking, electroejaculation, and testicular sperm extraction in males and cryopreservation of embryos or oocytes in females. This paper also highlights novel methods currently in development, such as gonadal tissue cryopreservation and in vitro maturation of gametes. In women, anti-Mullerian hormone is emerging as an accurate marker of ovarian reserve, and the use of gonadotropin releasing hormone analogs to protect fertility is increasingly well validated. Although national guidelines mandate FP counseling and referral prior to the start of cancer therapy for patients with reproductive potential, only a minority of young cancer patients in the USA currently take steps to preserve fertility prior to the start of therapy. Some cancer centers across the USA are developing institutional strategies to support FP, resulting in increased utilization of fertility services by newly diagnosed cancer patients. Keywords: young adult, cancer, fertility preservation, program, oocyte, sperm

  3. Evidence for bisphenol A-induced female infertility - Review (2007–2016)

    Science.gov (United States)

    Ziv-Gal, Ayelet; Flaws, Jodi A.

    2016-01-01

    We summarized the scientific literature published from 2007 to 2016 on the potential effects of bisphenol A (BPA) on female fertility. We focused on overall fertility outcomes (e.g., ability to become pregnant, number of offspring), organs that are important for female reproduction (i.e., oviduct, uterus, ovary, hypothalamus, and pituitary), and reproductive related processes (i.e., estrous cyclicity, implantation, and hormonal secretion). The reviewed literature indicates that BPA may be associated with infertility in women. Potential explanations for this association can be generated from experimental studies. Specifically, BPA may alter overall female reproductive capacity by affecting the morphology and function of the oviduct, uterus, ovary, and hypothalamus-pituitary-ovarian axis in animal models. Additionally, BPA may disrupt estrous cyclicity and implantation. Nevertheless, further studies are needed to better understand the exact mechanisms of action and to detect potential reproductive toxicity at earlier stages. PMID:27417731

  4. Lifestyle factors and reproductive health: taking control of your fertility.

    Science.gov (United States)

    Sharma, Rakesh; Biedenharn, Kelly R; Fedor, Jennifer M; Agarwal, Ashok

    2013-07-16

    Approximately 10 to 15% of couples are impacted by infertility. Recently, the pivotal role that lifestyle factors play in the development of infertility has generated a considerable amount of interest. Lifestyle factors are the modifiable habits and ways of life that can greatly influence overall health and well-being, including fertility. Many lifestyle factors such as the age at which to start a family, nutrition, weight, exercise, psychological stress, environmental and occupational exposures, and others can have substantial effects on fertility; lifestyle factors such as cigarette smoking, illicit drug use, and alcohol and caffeine consumption can negatively influence fertility while others such as preventative care may be beneficial. The present literature review encompasses multiple lifestyle factors and places infertility in context for the couple by focusing on both males and females; it aims to identify the roles that lifestyle factors play in determining reproductive status. The growing interest and amount of research in this field have made it evident that lifestyle factors have a significant impact on fertility.

  5. A STUDY OF FEMALE CIRCUMCISION AMONG THE ISOKO TRIBE ...

    African Journals Online (AJOL)

    drclement

    2009-12-01

    Dec 1, 2009 ... women's health, sexuality and fertility. Objective: To ... them showed a high significant rate of circumcision (66%) ... female genital cutting by its critics) has been practiced ..... mutilation is falling, indicating that it has decreasing ...

  6. Effects of gamma radiation on codling moth (Cydia pomonella, Lepidoptera: Tortricidae) fertility and reproductive behaviour

    International Nuclear Information System (INIS)

    Mansour, M.

    2002-01-01

    Studies were conducted with codling moth, Cydia pomonella (L.), to examine the effects of gamma radiation on fertility and reproductive behaviour. Data accumulated during these studies showed that egg production and hatch decreased with increasing radiation dose. Females were more sensitive to radiation treatment than were males. A dose of 150 Gy caused 100% sterility in females and significantly reduced fecundity, and a dose of 350 Gy reduced male fertility to less than 1%. Radiation dosages up to 400 Gy had no adverse effect on male longevity or competitiveness in cages using laboratory reared moths. However, males exposed to a dose of 350 or 400 Gy mated fewer times than unirradiated males. (author)

  7. The insults of illicit drug use on male fertility.

    Science.gov (United States)

    Fronczak, Carolyn M; Kim, Edward D; Barqawi, Al B

    2012-01-01

    One-third of infertile couples may have a male factor present. Illicit drug use can be an important cause of male factor infertility and includes use of anabolic-androgenic steroids, marijuana, opioid narcotics, cocaine, and methamphetamines. The use of these illicit drugs is common in the United States, with a yearly prevalence rate for any drug consistently higher in males compared with females. We aim to provide a review of recent literature on the prevalence and effects of illicit drug use on male fertility and to aid health professionals when counseling infertile men whose social history suggests illicit drug use. Anabolic-androgenic steroids, marijuana, cocaine, methamphetamines, and opioid narcotics all negatively impact male fertility, and adverse effects have been reported on the hypothalamic-pituitary-testicular axis, sperm function, and testicular structure. The use of illicit drugs is prevalent in our society and likely adversely impacting the fertility of men who abuse drugs.

  8. Characterization and fine mapping of a female fertility associated ...

    Indian Academy of Sciences (India)

    2015-03-12

    Mar 12, 2015 ... 1Key Laboratory of Agriculture Responding to Climate Change, Jiangxi ... Female-sterile line can be used as a pollinator which has a great potential for hybrid seeds production. ... Reciprocal crosses and pollen vitality assay suggest that the .... per plant, and seed-setting rate were investigated in ff1(t).

  9. Knowledge, attitudes, and intentions toward fertility awareness and oocyte cryopreservation among obstetrics and gynecology resident physicians.

    Science.gov (United States)

    Yu, L; Peterson, B; Inhorn, M C; Boehm, J K; Patrizio, P

    2016-02-01

    What knowledge, attitudes and intentions do US obstetrics and gynecology (OB/GYN) residents have toward discussing age-related fertility decline and oocyte cryopreservation with their patients? Most OB/GYN residents believe that age-related fertility decline, but not oocyte cryopreservation, should be discussed during well-woman annual exams; furthermore, nearly half of residents overestimated the age at which female fertility markedly declines. Oocyte cryopreservation can be utilized to preserve fertility potential. Currently, no studies of US OB/GYN residents exist that question their knowledge, attitudes, and intentions toward discussing age-related fertility decline and oocyte cryopreservation with patients. A cross-sectional online survey was conducted during the fall of 2014 among residents in American Council for Graduate (ACOG) Medical Education-approved OB/GYN residency programs. Program directors were emailed via the ACOG Council on Resident Education in Obstetrics and Gynecology server listing and asked to solicit resident participation. Participants included 238 residents evenly distributed between post-graduate years 1-4 with varied post-residency plans; 90% of residents were women and 75% were 26-30 years old. The survey was divided into three sections: demographics, fertility awareness, and attitudes toward discussing fertility preservation options with patients. Descriptive and inferential statistics were conducted. A strong majority of residents (83%) believed an OB/GYN should initiate discussions about age-related fertility decline with patients (mean patient age 31.8), and 73% percent believed these discussions should be part of an annual exam. One third of residents overestimated the age at which there is a slight decline in female fertility, while nearly half of residents overestimated the age at which female fertility markedly declines. Over three-quarters of residents (78.4%) also overestimated the likelihood of success using assisted

  10. Influence of heavy nanocrystals on spermatozoa and fertility of mammals

    Energy Technology Data Exchange (ETDEWEB)

    Akhavan, Omid, E-mail: oakhavan@sharif.edu [Department of Physics, Sharif University of Technology, P.O. Box 11155-9161, Tehran (Iran, Islamic Republic of); Institute for Nanoscience and Nanotechnology, Sharif University of Technology, P.O. Box 14588-89694, Tehran (Iran, Islamic Republic of); Hashemi, Ehsan [National Research Center for Transgenic Mouse, National Institute of Genetic Engineering and Biotechnology, P.O. Box 14965-161, Tehran (Iran, Islamic Republic of); Zare, Hakimeh [Physics Department, Yazd University, Yazd, P.O. Box 89195-741 (Iran, Islamic Republic of); Shamsara, Mehdi [National Research Center for Transgenic Mouse, National Institute of Genetic Engineering and Biotechnology, P.O. Box 14965-161, Tehran (Iran, Islamic Republic of); Taghavinia, Nima [Department of Physics, Sharif University of Technology, P.O. Box 11155-9161, Tehran (Iran, Islamic Republic of); Institute for Nanoscience and Nanotechnology, Sharif University of Technology, P.O. Box 14588-89694, Tehran (Iran, Islamic Republic of); Heidari, Farid [National Research Center for Transgenic Mouse, National Institute of Genetic Engineering and Biotechnology, P.O. Box 14965-161, Tehran (Iran, Islamic Republic of)

    2016-12-01

    In recent years, quantum dots (QDs) have been widely used in upcoming nanotechnology-based solar cells, light-emitting diodes and even bioimaging, due to their tunable optical properties and excellent quantum yields. But, such nanostructures are currently constituted by heavy elements which can threat the human health and living environment. Hence, in this work, the in vivo effects of CdTe nanocrystals (NCs) (as one of the promising QDs) on spermatozoa of male mice and subsequently on fertility of female mice were investigated, for the first time. To do this, CdTe NCs were synthesized through an environment-friendly (aqueous-based solution) method. The sperm cells presented a high potential for uptake of the heavy QDs. Meantime, the NCs exhibited concentration-dependent adverse effects on morphology, viability, kinetic characteristics and DNA of the spermatozoa. At low concentration of 0.1 μg/mL, the NCs showed a moderate toxicity (~ 25% reduction in viability and motility of the spermatozoa), while remarkable toxicities were observed at higher concentrations of 1.0–100 μg/mL (~ 67% reduction in viability and motility for 100 μg/mL). Furthermore, significant in vitro DNA fragmentation of the spermatozoa was observed at CdTe concentrations ≥ 10 μg/mL. In vivo toxicity of the NCs was found lower than the in vitro toxicity. Nevertheless, the in vivo destructive effects of the NCs still caused ~ 34% reduction in viability as well as motility and ~ 5% damages in DNA of male mice spermatozoa. These resulted in ~ 26% decrease in fertility and gestation of female mice, along with an overall hormone secretion during the pregnancy, and ~ 39% reduction in viability of pups/pregnant females. - Highlights: • The cytotoxic effects of CdTe nanocrystals on spermatozoa of male mice • High uptake of CdTe by spermatozoa, resulting in inactivation of spermatozoa or pollution of the others • The adverse effects of polluted spermatozoa on fertility/gestation of female mice

  11. Epidemiology of asexuality induced by the endosymbiotic Wolbachia across phytophagous wasp species: host plant specialization matters.

    Science.gov (United States)

    Boivin, T; Henri, H; Vavre, F; Gidoin, C; Veber, P; Candau, J-N; Magnoux, E; Roques, A; Auger-Rozenberg, M-A

    2014-05-01

    Among eukaryotes, sexual reproduction is by far the most predominant mode of reproduction. However, some systems maintaining sexuality appear particularly labile and raise intriguing questions on the evolutionary routes to asexuality. Thelytokous parthenogenesis is a form of spontaneous loss of sexuality leading to strong distortion of sex ratio towards females and resulting from mutation, hybridization or infection by bacterial endosymbionts. We investigated whether ecological specialization is a likely mechanism of spread of thelytoky within insect communities. Focusing on the highly specialized genus Megastigmus (Hymenoptera: Torymidae), we first performed a large literature survey to examine the distribution of thelytoky in these wasps across their respective obligate host plant families. Second, we tested for thelytoky caused by endosymbionts by screening in 15 arrhenotokous and 10 thelytokous species for Wolbachia, Cardinium, Arsenophonus and Rickettsia endosymbionts and by performing antibiotic treatments. Finally, we performed phylogenetic reconstructions using multilocus sequence typing (MLST) to examine the evolution of endosymbiont-mediated thelytoky in Megastigmus and its possible connections to host plant specialization. We demonstrate that thelytoky evolved from ancestral arrhenotoky through the horizontal transmission and the fixation of the parthenogenesis-inducing Wolbachia. We find that ecological specialization in Wolbachia's hosts was probably a critical driving force for Wolbachia infection and spread of thelytoky, but also a constraint. Our work further reinforces the hypothesis that community structure of insects is a major driver of the epidemiology of endosymbionts and that competitive interactions among closely related species may facilitate their horizontal transmission. © 2014 John Wiley & Sons Ltd.

  12. Reproductive Hormones Disorders Of Sudanese Infertile Females Using Immunoradiometric assay (IRMA)

    International Nuclear Information System (INIS)

    Ali, N. I.; Almahi, W. A. A.; Abdalla, O. M.; Bafarag, S. M. I.; Abdelgadir, O. M.; Eltayeb, M. A. H.; Hassan, A. M. E.; Hassan, A. M. E.

    2004-01-01

    In this study fertility hormones were measured for 587 infertile Sudanese female referred from gynecological clinics. The ages of these female ranges from 16 - 50 years divided into seven groups. Eighty seven percent of them are in the age range between 21 and 40 year which correlate with the female's fertile period and 5.6% of them under 20 years. Sensitive (IRMA) method was used for measuring the hormone concentration. The objective of this study was to found out the percentage of hormonal disorders and its relation to the age in infertile Sudanese females. The age group (21 - 25) was the most affected group by the Poly-Cystic Ovary Syndrome (PCOS) and represented 5.1% of the total number of patients. The least group was the age group (41- 45) with a percentage of 0.4. The LH and the FSH in the age group of (31- 35) was found to be higher than the other groups and represented 11.4% and 7.8% from the total number of patients respectively. The least percent of high level of LH and FSH was found to be in the most fertile age group (15 - 20) and it was 1.7% and 1.0% from the total number of studied patient, respectively. Those who were in the age range (26 - 30) with hyperprolactinemia represented 10.4% of patients, while those with age range (46 - 50) with hyperprolactinemia represented the lowest percentage (1.2%). The percentage of patients having high LH and high FSH was 44.5% and 29.1% respectively , while the hyperprolactinemia among the infertile Sudanese female was found to 38.2%. (Authors)

  13. Treating Woman with Myo-Inositol Vaginal Suppositories Improves Partner’s Sperm Motility and Fertility

    Directory of Open Access Journals (Sweden)

    Mario Montanino Oliva

    2016-01-01

    Full Text Available Motility is the feature that allows spermatozoa to actively reach and penetrate the female gamete during fertilization. When this function is altered, and especially decreased, troubles in conceiving may occur. In this study, we demonstrated that treating fertile women with myo-inositol (MI vaginal suppositories ameliorated their partners’ sperm motility and also positively affected their conceiving capacity, without changes in cervical mucus structural and biochemical characteristics. Indeed, by means of the postcoital test on female cervical mucus, a significant improvement especially in progressive sperm motility was recorded after MI suppository use. Concomitantly, after MI treatment, a reduction of immotile spermatozoa percentage was observed. Importantly, MI vaginal supplementation positively correlated with a pregnancy for 5 of the 50 couples enrolled in the study, leading us to speculate that this substance may substantially contribute to create in the cervical mucus an ideal milieu that makes spermatozoa more motile and functionally able to fertilize. Even though the detailed mechanism is still unclear, these results should encourage MI vaginal use for the clinical improvement of male infertility, through their partners.

  14. Endocrine autoimmune diseases and female infertility.

    Science.gov (United States)

    Sen, Aritro; Kushnir, Vitaly A; Barad, David H; Gleicher, Norbert

    2014-01-01

    An increasing body of evidence suggests that immune-mediated processes affect female reproductive success at multiple levels. Crosstalk between endocrine and immune systems regulates a large number of biological processes that affect target tissues, and this crosstalk involves gene expression, cytokine and/or lymphokine release and hormone action. In addition, endocrine-immune interactions have a major role in the implantation process of the fetal (paternally derived) semi-allograft, which requires a reprogramming process of the maternal immune system from rejection to temporary tolerance for the length of gestation. Usually, the female immune system is supportive of all of these processes and, therefore, facilitates reproductive success. Abnormalities of the female immune system, including autoimmunity, potentially interfere at multiple levels. The relevance of the immune system to female infertility is increasingly recognized by investigators, but clinically is often not adequately considered and is, therefore, underestimated. This Review summarizes the effect of individual autoimmune endocrine diseases on female fertility, and points towards selected developments expected in the near future.

  15. What explains uneven female labor force participation levels and trends in developing countries?

    OpenAIRE

    Klasen, Stephan

    2018-01-01

    Rapid fertility decline, a strong expansion of female education, and favorable economic conditions should have promoted female labor force participation in developing countries. Yet trends in female labor force participation (FLFP) have been quite heterogeneous, rising strongly in Latin America, stagnating in many other regions, while improvements were modest in the Middle East and female participation even fell in South Asia. These trends are inconsistent with secular theories such as the Fe...

  16. Female fertility following dose-adjusted EPOCH-R chemotherapy in primary mediastinal B-cell lymphomas.

    Science.gov (United States)

    Gharwan, Helen; Lai, Catherine; Grant, Cliona; Dunleavy, Kieron; Steinberg, Seth M; Shovlin, Margaret; Fojo, Tito; Wilson, Wyndham H

    2016-07-01

    We assessed fertility/gonadal function in premenopausal women treated with dose-adjusted EPOCH-Rituximab for untreated primary mediastinal B-cell lymphoma (PMBL). Eligible patents were ≤ 50 years and premenopausal. Serial reproductive histories were obtained and hormonal assays were performed on serum samples before, at the end of treatment and 4-18 months later. Twenty-eight eligible women had a median age (range) of 31 (21-50) years and were followed a median of 7.3 years. Of 23 patients who completed a questionnaire, 19 (83%) were and four were not menstruating prior to chemotherapy. Amenorrhea developed in 12 patients during chemotherapy. At > 1-year follow-up, 14/19 (74%) patients were menstruating, all years old, and six (43%) of these patients delivered healthy children. Hormonal assays showed ovarian dysfunction during chemotherapy in all patients with varying recovery at 4-18 months after treatment. Fertility was preserved in most women with ovarian failure confined to patients > 40 years old.

  17. Morphological alterations in the freshwater rotifer Brachionus calyciflorus Pallas 1766 (Rotifera: Monogononta) caused by vinclozolin chronic exposure.

    Science.gov (United States)

    Alvarado-Flores, Jesús; Rico-Martínez, Roberto; Adabache-Ortíz, Araceli; Silva-Briano, Marcelo

    2015-05-01

    Vinclozolin (VZ) is a dicarboximide fungicide widely used on fruits, vegetables and wines, effective against fungi plagues. In this study we characterized the effects of VZ using a 4-day reproductive chronic assay with the freshwater rotifer Brachionus calyciflorus. The assay included observations of several features of asexual and sexual reproduction. Our results indicate that VZ: (a) increased asexual and sexual reproduction, (b) caused severe abnormality in females and (c) these abnormalities were inherited by sexual and asexual reproduction. At 1.2 mg/L three abnormal females were found out of 457 total females (0.66 %). This low percentage is consistent and reproducible according to further analysis, where we increased the number of replicates and total females exposed to 1.2 mg/L of VZ, and found 18 abnormal females out of 2868 total females (0.63 % abnormality). Interestingly, abnormal females found at 5.6 mg/L VZ exposure, were able to show mating behavior. Our results suggest that VZ behaves as a strong endocrine disruptor whose effects show the characteristic inverted-U-shape exposure concentration response curve regarding the intrinsic population increase and the percentage of abnormalities as endpoints.

  18. Global Fertilizer and Manure, Version 1: Nitrogen Fertilizer Application

    Data.gov (United States)

    National Aeronautics and Space Administration — The Nitrogen Fertilizer Application dataset of the Global Fertilizer and Manure, Version 1 Data Collection represents the amount of nitrogen fertilizer nutrients...

  19. Global Fertilizer and Manure, Version 1: Phosphorus Fertilizer Application

    Data.gov (United States)

    National Aeronautics and Space Administration — The Phosphorus Fertilizer Application dataset of the Global Fertilizer and Manure, Version 1 Data Collection represents the amount of phosphorus fertilizer nutrients...

  20. [Association between the decline in global fertility rate and the incorporation of women to the workforce].

    Science.gov (United States)

    Stefanelli, María de Los Ángeles; Valenzuela, María Teresa; Cárcamo, Marcela; Urquidi, Cinthya; Cavada, Gabriel; San Martín P, Pamela

    2016-05-01

    The global fertility rate (GFR) is defined as the mean number of children that a woman could have in a hypothetical cohort, not exposed to death during the fertile period. GFR has fallen from 3.4 to 1.9 children per women in the period 1970-2010. To explore the relationship between the fall in GFR and the incorporation of women to work in the period 1960-2011. Data from the National Statistics Institute was used. GRF was calculated using specific fertility rates for each year considering women aged 15 to 49 years. Work rates were obtained from yearly vital statistics reports. Between 1960 and 2011, GRF decreased from 5.5 to 1.9 in Chile. The first inflection occurred in 1970. In the same period, female workforce increased from 22.4 to 40.2%. To motivate the participation of female work-force without decrease the GRF allowing population replacement, it is suggested the need to create new public policies with benefits and support from the state.

  1. Structural and diffusion effects in the Dutch fertility transition, 1870-1940

    Directory of Open Access Journals (Sweden)

    Hilde Bras

    2014-01-01

    Full Text Available Background: Ever since the Princeton European Fertility Project, structural and diffusion effects on fertility behavior have been juxtaposed. However, we still hardly know what the relative effects were of shifting socio-economic conditions and shifts in sociability in explaining the historical fertility decline. Objective: To what extent and how did structural and diffusion effects play a role in the adoption of fertility control in the Dutch historical fertility transition? Methods: A national data set was used with more than 3,000 maternity histories of married Dutch women aged 15-50, whose reproductive careers took place between 1870 and 1940. Apart from husbands' occupations, characteristics of the set of couples' marriage witnesses were included to measure their social networks. Cox regression analyses of age at last birth and negative binomial regressions of net family size were conducted. Results: Results indicate that unskilled laborers and farm laborers were laggards in the practice of fertility control during the Dutch fertility transition. Besides SES differentials, differences in couples' social networks were important in explaining fertility behavior. Those who had networks consisting of lateral kin, age peers, and people of urban background stopped childbearing earlier and had smaller families than other couples did. Particularly the presence of lateral kin of the bride and of female witnesses was strongly associated with smaller family size. Conclusions: The evidence lends support for so-called "blended diffusion models" and suggests that the fertility transition must be understood as much from the viewpoint of changed cost-benefit calculations related to structural changes, as from shifting patterns of sociability associated with the decline of patriarchy and the increasing lateralization and age homophily of people's social networks.

  2. Evaluation of the anti-fertility activity of stem bark of Crataeva ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-11-16

    Nov 16, 2009 ... The data was also analyzed by one way ANOVA followed by Dunnett Multiple Comparison Test. Test animals. Anti-fertility testing was performed on adult female Wister rats weighing between 180-200 g which was obtained from M/S. Venkateshwara enterprises (P) Ltd Bangalore. They were housed.

  3. A novel male sterility-fertility restoration system in plants for hybrid seed production.

    Science.gov (United States)

    Singh, Surendra Pratap; Singh, Sudhir P; Pandey, Tripti; Singh, Ram Rakshpal; Sawant, Samir V

    2015-06-15

    Hybrid seeds are used for stimulated crop production, as they harness heterosis. The achievement of complete male-sterility in the female-parent and the restored-fertility in F1-hybrids are the major bottlenecks in the commercial hybrid seed production. Here, we report a male sterility-fertility restoration system by engineering the in most nutritive anther wall layer tapetum of female and male parents. In the female parent, high-level, and stringent expression of Arabidopsis autophagy-related gene BECLIN1 was achieved in the tapetum, which altered the tapetal degeneration program, leading to male sterility. This works on our previously demonstrated expression cassette based on functional complementation of TATA-box mutant (TGTA) promoter and TATA-binding protein mutant3 (TBPm3), with modification by conjugating Long Hypocotyle in Far-Red1 fragment (HFR1(NT131)) with TBPm3 (HFR1(NT131)-TBPm3) to exercise regulatory control over it. In the male parent, tapetum-specific Constitutive photo-morphogenesis1 (COP1) was expressed. The F1 obtained by crossing these engineered parents showed decreased BECLIN1 expression, which was further completely abolished when COP1-mutant (COP1(L105A)) was used as a male parent, leading to normal tapetal development and restored fertility. The system works on COP1-HFR1 interaction and COP1-mediated degradation of TBPm3 pool (HFR1(NT131)-TBPm3). The system can be deployed for hybrid seed production in agricultural crops.

  4. Intraovarian Transplantation of Female Germline Stem Cells Rescue Ovarian Function in Chemotherapy-Injured Ovaries.

    Directory of Open Access Journals (Sweden)

    Jiaqiang Xiong

    Full Text Available Early menopause and infertility often occur in female cancer patients after chemotherapy (CTx. For these patients, oocyte/embryo cryopreservation or ovarian tissue cryopreservation is the current modality for fertility preservation. However, the above methods are limited in the long-term protection of ovarian function, especially for fertility preservation (very few females with cancer have achieved pregnancy with cryopreserved ovarian tissue or eggs until now. In addition, the above methods are subject to their scope (females with no husband or prepubertal females with no mature oocytes. Thus, many females who suffer from cancers would not adopt the above methods pre- and post-CTx due to their uncertainty, safety and cost-effectiveness. Therefore, millions of women have achieved long-term survival after thorough CTx treatment and have desired to rescue their ovarian function and fertility with economic, durable and reliable methods. Recently, some studies showed that mice with infertility caused by CTx can produce normal offspring through intraovarian injection of exogenous female germline stem cells (FGSCs. Though exogenous FGSC can be derived from mice without immune rejection in the same strain, it is difficult to obtain human female germline stem cells (hFGSCs, and immune rejection could occur between different individuals. In this study, infertility in mice was caused by CTx, and the ability of FGSCs to restore ovarian function or even produce offspring was assessed. We had successfully isolated and purified the FGSCs from adult female mice two weeks after CTx. After infection with GFP-carrying virus, the FGSCs were transplanted into ovaries of mice with infertility caused by CTx. Finally, ovarian function was restored and the recipients produced offspring long-term. These findings showed that mice with CTx possessed FGSCs, restoring ovarian function and avoiding immune rejection from exogenous germline stem cells.

  5. Intraovarian Transplantation of Female Germline Stem Cells Rescue Ovarian Function in Chemotherapy-Injured Ovaries.

    Science.gov (United States)

    Xiong, Jiaqiang; Lu, Zhiyong; Wu, Meng; Zhang, Jinjin; Cheng, Jing; Luo, Aiyue; Shen, Wei; Fang, Li; Zhou, Su; Wang, Shixuan

    2015-01-01

    Early menopause and infertility often occur in female cancer patients after chemotherapy (CTx). For these patients, oocyte/embryo cryopreservation or ovarian tissue cryopreservation is the current modality for fertility preservation. However, the above methods are limited in the long-term protection of ovarian function, especially for fertility preservation (very few females with cancer have achieved pregnancy with cryopreserved ovarian tissue or eggs until now). In addition, the above methods are subject to their scope (females with no husband or prepubertal females with no mature oocytes). Thus, many females who suffer from cancers would not adopt the above methods pre- and post-CTx due to their uncertainty, safety and cost-effectiveness. Therefore, millions of women have achieved long-term survival after thorough CTx treatment and have desired to rescue their ovarian function and fertility with economic, durable and reliable methods. Recently, some studies showed that mice with infertility caused by CTx can produce normal offspring through intraovarian injection of exogenous female germline stem cells (FGSCs). Though exogenous FGSC can be derived from mice without immune rejection in the same strain, it is difficult to obtain human female germline stem cells (hFGSCs), and immune rejection could occur between different individuals. In this study, infertility in mice was caused by CTx, and the ability of FGSCs to restore ovarian function or even produce offspring was assessed. We had successfully isolated and purified the FGSCs from adult female mice two weeks after CTx. After infection with GFP-carrying virus, the FGSCs were transplanted into ovaries of mice with infertility caused by CTx. Finally, ovarian function was restored and the recipients produced offspring long-term. These findings showed that mice with CTx possessed FGSCs, restoring ovarian function and avoiding immune rejection from exogenous germline stem cells.

  6. Fertility trends in Singapore.

    Science.gov (United States)

    Singh, K; Viegas, O; Ratnam, S S

    1988-10-01

    In 1966, the Singapore National Family Planning and Population Program established the goal of reaching replacement fertility by 1990 and zero population growth by the year 2030. To achieve this goal, the government relied on a series of incentives and disincentives to discourage births above the 3rd birth order, including tax relief for the 1st 3 children only, paid medical leave for women undergoing sterilization after the 3rd or subsequent birth, monetary stipends in some cases where the mother is sterilized after the 1st or 2nd birth, and increasing accouchement charges for increasing birth orders. Also important to demographic planning were liberalization of Singapore's abortion legislation and more aggressive promotion of contraception. As a result of these efforts, Singapore's crude birth rate has declined from 29.5/1000 population in 1965 to 16.6/1000 in 1985. Also observed have been dramatic declines in infant mortality in this same period, from 26.2/1000 live births to 9.3/1000, and in maternal mortality, from 52/100,000 live births to 10/100,000. In 1985, 42% of total births were to women in the 25-29-year age group. The numbers of 4th and later births fell by 90% between 1966 and 1985. The total fertility rate has declined from 4.6/woman in 1965 to 3.1 in 1970 to 1.6 in 1986. Below replacement level fertility was achieved in 1975, in part because of government policy but also as a result of cultural and socioeconomic factors such as increasing female labor force participation rates, a break-up of the extended family system, a rise in the age at 1st marriage, and rises in educational attainment. The drop in fertility was contributed mainly by the higher socioeconomic class, more affluent, and educated Singaporeans. Thus, in 1981, the government introduced certain pronatalist policies and incentives to encourage better educated women to produce more children, e.g., tax relief and the elimination of monetary incentives to sterilization acceptors above a

  7. An intact Pms2 ATPase domain is not essential for male fertility.

    Science.gov (United States)

    Fischer, Jared M; Dudley, Sandra; Miller, Ashleigh J; Liskay, R Michael

    2016-03-01

    The DNA mismatch repair (MMR) machinery in mammals plays critical roles in both mutation avoidance and spermatogenesis. Meiotic analysis of knockout mice of two different MMR genes, Mlh1 and Mlh3, revealed both male and female infertility associated with a defect in meiotic crossing over. In contrast, another MMR gene knockout, Pms2 (Pms2(ko/ko)), which contained a deletion of a portion of the ATPase domain, produced animals that were male sterile but female fertile. However, the meiotic phenotype of Pms2(ko/ko) males was less clear-cut than for Mlh1- or Mlh3-deficient meiosis. More recently, we generated a different Pms2 mutant allele (Pms2(cre)), which results in deletion of the same portion of the ATPase domain. Surprisingly, Pms2(cre/cre) male mice were completely fertile, suggesting that the ATPase domain of Pms2 is not required for male fertility. To explore the difference in male fertility, we examined the Pms2 RNA and found that alternative splicing of the Pms2(cre) allele results in a predicted Pms2 containing the C-terminus, which contains the Mlh1-interaction domain, a possible candidate for stabilizing Mlh1 levels. To study further the basis of male fertility, we examined Mlh1 levels in testes and found that whereas Pms2 loss in Pms2(ko/ko) mice results in severely reduced levels of Mlh1 expression in the testes, Mlh1 levels in Pms2(cre/cre) testes were reduced to a lesser extent. Thus, we propose that a primary function of Pms2 during spermatogenesis is to stabilize Mlh1 levels prior to its critical crossing over function with Mlh3. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Mapping of fertility traits in Finnish Ayrshire by genome-wide association analysis

    DEFF Research Database (Denmark)

    Schulmann, Nina F; Sahana, Goutam; Iso-Touru, T

    2011-01-01

    A whole-genome scan using single marker association was used to detect chromosome regions associated with seven female fertility traits in Finnish Ayrshire dairy cattle. The phenotypic data consisted of de-regressed estimated breeding values for 340 bulls which were estimated using a single trait...

  9. Fertility among descendants of immigrants in Belgium: The role of the partner

    NARCIS (Netherlands)

    Van Landschoot, L.; de Valk, H.A.G.; Van Bavel, J.

    2017-01-01

    BACKGROUND Research on the fertility behavior of descendants of immigrants has focused on female characteristics and has largely neglected those of the male partner. One key aspect is whether the partner is of same (endogamous) or of different (exogamous) ethnic origin. Moreover, the male partner

  10. Fusion: a tale of recombination in an asexual fungus: The role of nuclear dynamics and hyphal fusion in horizontal chromosome transfer in Fusarium oxysporum

    NARCIS (Netherlands)

    Shahi, S.

    2016-01-01

    Recent studies have shown that not only meiotic recombination is responsible for the fast evolution of fungal pathogens. In the asexual fungus F. oxysporum (Fo) the "fast" evolving part of the genome is organized into small chromosomes and one such chromosome houses all effector genes and is

  11. Quantification of egg proteome changes during fertilization in sterlet Acipenser ruthenus.

    Science.gov (United States)

    Niksirat, Hamid; Andersson, Liselotte; Golpour, Amin; Chupani, Latifeh; James, Peter

    2017-08-19

    Eggs of sterlet are discharged outside into ambient aquatic environment where egg activation and fertilization occur. Effects of different activation media including freshwater and clay suspension on protein abundances of egg were quantified in sterlet Acipenser ruthenus. In-gel digestion and high resolution mass spectrometry were used for label-free protein quantification in the eggs of five females. No significant (p > 0.05) difference was found between protein abundances in eggs activated with different media. However, results showed significant (p eggs as control. The fact that abundance of proteasome subunit alpha significantly reduced only in eggs which were activated by clay suspension suggests that activation medium can somehow intervene with protein regulation during fertilization. In conclusion, external fertilization in sturgeon egg is accompanied by huge release of proteins into the external environment that may participate in the construction of a transient microenvironment around egg for attraction and protection of spermatozoa to ensure ensuing fertilization. Data are available via ProteomeXchange with identifier PXD006232. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Effects of Dietary Vitamin E on Fertility Functions in Poultry Species

    Directory of Open Access Journals (Sweden)

    Deivendran Rengaraj

    2015-04-01

    Full Text Available Vitamin E is found in high quantities in vegetable oils. Although vitamin E has multiple functions in humans and animals, its key function is protecting cells from oxidative damage. Since its discovery, several studies have demonstrated that vitamin E deficiency causes impaired fertility in humans and lab animals. However, the effects of vitamin E deficiency or of its supplementation on the fertility of farm animals, particularly on poultry, are less well studied. Therefore, a comprehensive review of the effects of dietary vitamin E on the fertility of poultry species is needed in order to understand the beneficial role of vitamin E in the maintenance of sperm and egg qualities. Based on the observations reviewed here, we found that a moderate amount of vitamin E in poultry diet significantly protects semen/sperm qualities in male birds and egg qualities in female birds via decreasing the lipid peroxidation in semen/sperms and eggs. This review provides an overall understanding of the effects of dietary vitamin E on fertility functions in poultry species.

  13. [Nutrition and fertility].

    Science.gov (United States)

    Szostak-Węgierek, Dorota

    2011-01-01

    There is a growing body of evidence that nutritional habits may have a significant effect on both male and female fertility. Maintenance of normal body mass may be effective in the prevention of infertility resulting from ovulatory disorders. Underweight and, to a larger degree, overweight and/or obesity, are related to the enhanced risk of infertility. Insulin resistance is an important pathogenic mechanism that may impair ovulation. Adequate intake of monounsaturated fatty acids, derived mainly from vegetable fats, as well as avoidance of trans isomers of unsaturated fatty acids which are present in industrially produced cakes and sweets, crisps, fast-foods, powdered soups and hard margarines, may be effective in the prevention of infertility in females. Choice of plant rather than animal sources of proteins, decrease in glycemic load of the diet, use of dietary supplements containing iron and folic acid, could also be beneficial. Avoidance of vitamin B12 deficiency and its supplementation seem to be important in the prevention of early miscarriages. Sufficient intake of antioxidants also promotes female reproductive functions. Free radical processes play an important role in the development of male factor infertility. It was shown that proper intake or supplementation with antioxidants may be effective in its prevention and treatment. Such nutrients as zinc, selenium and folic acid act beneficially on sperm quality. A well-balanced diet seems to play an important role in the prevention of infertility in both sexes.

  14. Smoke, alcohol and drug addiction and male fertility.

    Science.gov (United States)

    Sansone, Andrea; Di Dato, Carla; de Angelis, Cristina; Menafra, Davide; Pozza, Carlotta; Pivonello, Rosario; Isidori, Andrea; Gianfrilli, Daniele

    2018-01-15

    In recent decades, the decline in human fertility has become increasingly more worrying: while therapeutic interventions might help, they are vexing for the couple and often burdened with high failure rates and costs. Prevention is the most successful approach to fertility disorders in males and females alike. We performed a literature review on three of the most common unhealthy habits - tobacco, alcohol and drug addiction - and their reported effects on male fertility. Tobacco smoking is remarkably common in most first-world countries; despite a progressive decline in the US, recent reports suggest a prevalence of more than 30% in subjects of reproductive age - a disturbing perspective, given the well-known ill-effects on reproductive and sexual function as well as general health. Alcohol consumption is often considered socially acceptable, but its negative effects on gonadal function have been consistently reported in the last 30 years. Several studies have reported a variety of negative effects on male fertility following drug abuse - a worrying phenomenon, as illicit drug consumption is on the rise, most notably in younger subjects. While evidence in these regards is still far from solid, mostly as a result of several confounding factors, it is safe to assume that cessation of tobacco smoking, alcohol consumption and recreational drug addiction might represent the best course of action for any couple trying to achieve pregnancy.

  15. New Conceptions: Biosocial Innovations and the Family.

    Science.gov (United States)

    Edwards, John N.

    1991-01-01

    Discusses asexual reproductive technologies (in vitro fertilization, cryopreservation, artificial insemination, sperm banks, genetic engineering, ovum transfer, cloning, ectogenesis, surrogacy) and suggests that theoretical implications of technologies may bring dramatic social changes in the family. Outlines symbolically representational…

  16. Suppression of fertility in adult cats

    DEFF Research Database (Denmark)

    Goericke-Pesch, Sandra Kathrin; Wehrend, A.; Georgiev, P.

    2014-01-01

    /needed? (iii) sex of the animal? New effective and available methods for hormonal contraception include melatonin implants for short-term post ponement of oestrus in adult queens and slow-release GnRH-agonist implants containing deslorelin (Suprelorin®) for short- and long-term contraception in male and female......Contents: Cats are animals with highly efficient reproduction, clearly pointing to a need for suppression of fertility. Although surgical contraception is highly effective, it is not always the method of choice. This is predominantly because it is cost-intensive, time-consuming and irreversible......, with the latter being of major importance for cat breeders. This article reviews the use of progestins, scleroting agents, immunocontraception, melatonin, GnRH antagonists and finally, GnRH agonists, in adult male and female cats in detail, according to the present state of the art. By now, various scientific...

  17. Educational differentials in cohort fertility during the fertility transition in South Korea

    Directory of Open Access Journals (Sweden)

    Sam Hyun Yoo

    2014-05-01

    Full Text Available Background: While there has been a considerable amount of research on the association between women's education and fertility rates, few of these studies have examined the pattern of fertility differentials over the course of the fertility transition. As a country that has experienced a rapid decline in fertility and marked improvements in women's educational attainment over the last several decades, South Korea represents an ideal case for studying this dynamic association. Objective: The aim of the article is to explain the pattern of fertility differentials by level of education and the contribution of the changes in women's educational attainment to the fertility decline during the fertility transition in South Korea. Methods: Drawing upon data from the Korean censuses conducted between 1970 and 2010, I analyze completed cohort fertility for women born between 1926 and 1970 using demographic-decomposition techniques and cohort parity progression ratios by level of education. Results: The differences in fertility by educational attainment have gradually declined over the transition, with fertility almost converging at a low level among recent birth cohorts. Fertility in South Korea had been declining in all of the social groups until the sub-replacement fertility was reached. The change in women's educational attainment then became an important factor in the further decline in fertility. The trend toward fewer children quickly spread from the most educated to the least educated women throughout the fertility transition. Conclusions: The transformation of fertility behaviors across social strata has been a key element in the Korean fertility transition. Although educational expansion, particularly the introduction of mass education, has contributed to falling fertility in South Korea, the role of education in fertility decline is more pronounced in the diffusion of innovative ideas and behaviors, which reduced fertility differentials across

  18. Fertility signals in the bumblebee Bombus terrestris (Hymenoptera: Apidae)

    Science.gov (United States)

    Sramkova, A.; Schulz, C.; Twele, R.; Francke, W.; Ayasse, M.

    2008-06-01

    In eusocial Hymenoptera, queen control over workers is probably inseparable from the mechanism of queen recognition. In primitively eusocial bumblebees ( Bombus), worker reproduction is controlled not only by the presence or absence of a dominant queen but also by other dominant workers. Furthermore, it was shown that the queen dominance is maintained by pheromonal cues. We investigated whether there is a similar odor signal released by egg-laying queens and workers that may have a function as a fertility signal. We collected cuticular surface extracts from nest-searching and breeding Bombus terrestris queens and workers that were characterized by their ovarian stages. In chemical analyses, we identified 61 compounds consisting of aldehydes, alkanes, alkenes, and fatty acid esters. Nest-searching queens and all groups of breeding females differed significantly in their odor bouquets. Furthermore, workers before the competition point (time point of colony development where workers start to develop ovaries and lay eggs) differed largely from queens and all other groups of workers. Breeding queens showed a unique bouquet of chemical compounds and certain queen-specific compounds, and the differences toward workers decrease with an increasing development of the workers’ ovaries, hinting the presence of a reliable fertility signal. Among the worker groups, the smallest differences were found after the competition point. Egg-laying females contained higher total amounts of chemical compounds and of relative proportions of wax-type esters and aldehydes than nest-searching queens and workers before the competition point. Therefore, these compounds may have a function as a fertility signal present in queens and workers.

  19. The Self-Regulation Effect of Fertility Status on Inbreeding Aversion: When Fertile, Disgust Increases more in Response to Descriptions of One's Own than of Others' Inbreeding

    Directory of Open Access Journals (Sweden)

    Jan Antfolk

    2014-07-01

    Full Text Available The ovulatory shift modulates emotions related to female sexuality. Because fertility status only affects the individual's own opportunity cost, the adaptive value of this shift is expected to stem from self-regulation. To test this assumption we asked women to contemplate various inbreeding descriptions: 1 they themselves having sex with male relatives; 2 their sister having sex with their common male relatives; and 3 an unrelated woman having sex with her male relatives (in 1, but not 2 and 3, negative fitness consequences are affected by the participant's fertility. We dichotomized the dependent variable disgust (ceiling vs. non-ceiling and analyzed the interaction between fertility status and description type. The ovulatory shift was stronger in descriptions where they themselves were described as engaging in inbreeding. A smaller increase was also found in reactions to others engaging in inbreeding. We explain the latter effect as due to self-reflection.

  20. Improvement in genetic evaluation of female fertility in dairy cattle using multiple-trait models including milk production traits

    DEFF Research Database (Denmark)

    Sun, C; Madsen, P; Lund, M S

    2010-01-01

    This study investigated the improvement in genetic evaluation of fertility traits by using production traits as secondary traits (MILK = 305-d milk yield, FAT = 305-d fat yield, and PROT = 305-d protein yield). Data including 471,742 records from first lactations of Denmark Holstein cows, covering...... the years of inseminations during first lactations from 1995 to 2004, were analyzed. Six fertility traits (i.e., interval in days from calving to first insemination, calving interval, days open, interval in days from first to last insemination, numbers of inseminations per conception, and nonreturn rate...... stability and predictive ability than single-trait models for all the fertility traits, except for nonreturn rate within 56 d after first service. The stability and predictive ability for the model including MILK or PROT were similar to the model including all 3 milk production traits and better than...

  1. Fertilization in Flowering Plants: 1. Bringing the Male and Female

    Indian Academy of Sciences (India)

    Crop productivity, floral advertisements, plant diversity, pollination, pollinators, pollination by deceit, stigma, anther, nectar, sexual deception. ... As plants lack mobility, they cannot perform, ontheir own, the most important and primary requirement ofbringing the male (pollen grain) and the female (pistil) partnerstogether.

  2. Puberty and Fertility of Ewe Lambs Fed on By-products of Palm and Olive Oil

    International Nuclear Information System (INIS)

    EL-T arabany, A.A.; Mostafa, M.M.M.; Mohamed, A.K.

    2017-01-01

    The present study aims to elucidate the effect of palm and olive oil by-products adding to rations on production and reproductive performance of Rahmani and Osimi female sheep. After weaning, Rahmani and Osimi ewe lambs (24 for each) of similar birth type were identified to compare between two rations containing hard fatty acids (HFA) or olive cake (OC) on sexual puberty and fertility of two breeds. The lambs of both breed were randomly divided into three groups: the first group is considered control and received ration which contained concentrate feed mixture (CFM). The second group nourished (OC) consisted of CFM +HFA and the third group nourished (HFA) composed of CFM +OC. The CFM was offered as basal ration to all experimental lambs. Body weight, functions of the liver, kidney, thyroid and progesterone hormones at puberty, and the fertility traits were assayed in the two breeds of ewes. The average body weight of female lambs was higher (P<0.05) with OC than HFA. Female lambs supplied OC reached puberty faster and their thyroid and sexual hormones (progesterone) have been developed earlier than ewe lambs given HFA and those in the control group. Age at puberty and progesterone level in both Rahmani and Osimi ewe lambs were better in ewes fed on OC , than other two groups. The fertility (%) from total ewe lambs and birth weight in ewe lambs fed on OC were higher than ewes fed on HFA and the control. It may be concluded that feeding ewe lambs on diet containing HFA from weaning had positive effects on age at puberty, reproductive fertility and prolificacy

  3. Effect of Various Organic Fertilizers Substitute Chemical Fertilizer on Cucumber Productions

    International Nuclear Information System (INIS)

    Piadang, Nattayana; Ratanapanit, Sittisuk; Chaowanklang, Pratuang; Ratanapanit; Nadtinee; Jaipakdee, Putinee; Ongsakitboriboon

    2006-09-01

    The effect of using the various organic fertilizer to substitute on the chemical fertilizer on cucumber, was carried out at Tambol Pattananikom, Amphur Pattananikom, Lopburi, Thailand, from December 1, 2005 to February 1, 2006 By using Randomized Comp let Block Design (RCBD), Contain with 4 treatments, chemical fertilizer: 16-16-16: 40 Kg/rai (Control), Pillet organic fertilizer: 50 Kg/rai, Bio extract from cow milk: 300 cc./ water 20 Ltr,.+ compost mixed in soil and bio fertilizer from the office of Atomic Energy Peace : 300 cc./water 20 Ltr. + campost mixed in soil (15 m. 2 /plot) were compared. Experiment result indicate that there were no significant differences on the yield. The highest yield of 25.91 kg/plot (27663.73 kg/rai) was obtained from chemical fertilizer, Fertilizer, followed by pillet organic fertilizer 22.88 kg/plot (2440.53 kg/rai), bio fertilizer 22.34 kg/pot (2382.93 kg/rai) and bio extract 19.03 kg/plot) (2029.87 kg/rai.

  4. Oestradiol and prostaglandin F2α regulate sexual displays in females of a sex-role reversed fish

    Science.gov (United States)

    Gonçalves, David; Costa, Silvia Santos; Teles, Magda C.; Silva, Helena; Inglês, Mafalda; Oliveira, Rui F.

    2014-01-01

    The mechanisms regulating sexual behaviours in female vertebrates are still poorly understood, mainly because in most species sexual displays in females are more subtle and less frequent than displays in males. In a sex-role reversed population of a teleost fish, the peacock blenny Salaria pavo, an external fertilizer, females are the courting sex and their sexual displays are conspicuous and unambiguous. We took advantage of this to investigate the role of ovarian-synthesized hormones in the induction of sexual displays in females. In particular, the effects of the sex steroids oestradiol (E2) and testosterone (T) and of the prostaglandin F2α (PGF2α) were tested. Females were ovariectomized and their sexual behaviour tested 7 days (sex steroids and PGF2α) and 14 days (sex steroids) after ovariectomy by presenting females to an established nesting male. Ovariectomy reduced the expression of sexual behaviours, although a significant proportion of females still courted the male 14 days after the ovary removal. Administration of PGF2α to ovariectomized females recovered the frequency of approaches to the male's nest and of courtship displays towards the nesting male. However, E2 also had a positive effect on sexual behaviour, particularly on the frequency of approaches to the male's nest. T administration failed to recover sexual behaviours in ovariectomized females. These results suggest that the increase in E2 levels postulated to occur during the breeding season facilitates female mate-searching and assessment behaviours, whereas PGF2α acts as a short-latency endogenous signal informing the brain that oocytes are mature and ready to be spawned. In the light of these results, the classical view for female fishes, that sex steroids maintain sexual behaviour in internal fertilizers and that prostaglandins activate spawning behaviours in external fertilizers, needs to be reviewed. PMID:24452030

  5. Fertilization and Embryo Development of Fresh and Cryopreserved Sibling Oocytes

    Directory of Open Access Journals (Sweden)

    Robert F. Casper

    2010-01-01

    Full Text Available Background: Oocyte cryopreservation is potentially the best way to preserve female fertility forunmarried women or young girls at risk of losing ovarian function. The aim of this study was tocompare fertilization and embryo development in frozen-thawed oocytes to their fresh siblings inwomen undergoing in vitro fertilization (IVF and embryo transfer (ET.Materials and Methods: Eleven infertile women undergoing infertility treatment, between theages of 24 to 37 years (mean ± SD = 31.6 ± 3.5, were included in this study. Mature oocytesfrom each patient were randomized into cryopreserved and fresh groups prior to intracytoplasmicsperm injection (ICSI. One hundred and thirty nine oocytes were retrieved, of which 105 were atmetaphase II (MII. Forty- five fresh MII oocytes were kept in culture whereas their sibling 60 MIIoocytes were cryopreserved using a slow cooling protocol. The frozen oocytes remained in LN2for 2 hours before thawing. ICSI was performed 1-2 hours after thawing for frozen oocytes and 4-5hours after retrieval for fresh oocytes. Fertilization and embryo development were compared.Results: Following thawing, 31 oocytes (51.6 % survived and 22 fertilized (79% while 32 freshoocytes fertilized upon ICSI (71%. The mean ± SE scores for embryos developing from frozenthawedoocytes were significantly lower at 48 and 72 hours post-ICSI than for embryos resultingfrom fresh oocytes (p<0.05.Conclusion: Our data demonstrated that oocyte freezing resulted in acceptable survival ratesfollowing cryopreservation, and similar fertilization rates following ICSI as compared to the freshsibling oocytes. However the number of blastomeres and the embryo quality on day three wassuperior in embryos from fresh oocytes when compared to the frozen oocytes.

  6. Environmental control of asexual reproduction and somatic growth of Aurelia spp. (Cnidaria, Scyphozoa) polyps from the Adriatic Sea

    OpenAIRE

    Hubot, Nathan; Lucas, Cathy H.; Piraino, Stefano

    2017-01-01

    Polyps of two moon jellyfish species, Aurelia coerulea and A.relicta, from two Adriatic Sea coastal habitats were incubated under multiple combinations of temperature (14, 21 °C), salinity (24, 37 ppt) and food regime (9.3, 18.6, 27.9 μg C ind‾¹ week‾¹) to comparatively assess how these factors may influence major asexual reproduction processes in the two species. Both species exhibited a shared pattern of budding mode (Directly Budded Polyps: DBP; Stolonal Budded Polyps: SBP), with DBP favo...

  7. Fertility preservation in children and young adults undergoing treatment for malignancy

    International Nuclear Information System (INIS)

    Al-Fozan, Haya M.; Tulandi, Togas

    2004-01-01

    Advances in cancer therapy have improved the long term survival of young patients suffering from malignancies. However adverse effects of the treatment are sterlity and loss of gonadal function especially in females. Preservation of fertility in males by sperm freezing is more practical and already established. For young women undergoing cancer treatment , the availability of preserving the gonadal function and fertility has just begun.Today we can crypreserve the oocytes, the embryos or rhe ovarian tissue and those undergoing pelvic irradtion, laparascopic can be cnsidered. Because women with non-gynelical malagnencies seek advice from a general surgeon or a medical onconologist, increasing awawreness of physician and general public is recommended. (author)

  8. An intact Pms2 ATPase domain is not essential for male fertility

    OpenAIRE

    Fischer, Jared M; Dudley, Sandra; Miller, Ashleigh J; Liskay, R Michael

    2015-01-01

    The DNA mismatch repair (MMR) machinery in mammals plays critical roles in both mutation avoidance and spermatogenesis. Meiotic analysis of knockout mice of two different MMR genes, Mlh1 and Mlh3, revealed both male and female infertility associated with a defect in meiotic crossing over. In contrast, another MMR gene knockout, Pms2 (Pms2ko/ko), which contained a deletion of a portion of the ATPase domain, produced animals that were male sterile but female fertile. However, the meiotic phenot...

  9. Fertility life table of Lysiphlebus testaceipes (Cresson) (Hymenoptera, Braconidae, Aphidiinae) in Rhopalosiphum maidis (Fitch) and Aphis gossypii Glover (Hemiptera, Aphididae)

    International Nuclear Information System (INIS)

    Silva, Robson Jose da; Bueno, Vanda Helena Paes; Silva, Diego Bastos; Sampaio, Marcus Vinicius

    2008-01-01

    Fertility life table of Lysiphlebus testaceipes (Cresson) (Hymenoptera, Braconidae, Aphidiinae) in Rhopalosiphum maidis (Fitch) and Aphis gossypii Glover (Hemiptera, Aphididae). The evaluation of the growth potential of Lysiphlebus testaceipes (Cresson) is important for its use in biological control programs of aphids. This work aimed to evaluate the fertility life table of L. testaceipes in Rhopalosiphum maidis (Fitch) and Aphis gossypii Glover. To determine the immature mortality, development and the sex ratio of the parasitoid, 12 females parasitoid, and 480 nymphs of each aphids were used. To evaluate the longevity and fertility 15 female parasitoid were used. Nymphs of each aphid (3 day old) were offered for each parasitoid female daily, until the female died, being 300 (first day); 250 (second day); 200 (third day); 150 (fourth day) and 50 nymphs in the other days. L. testaceipes showed immature mortality rates of 5.6 % in R. maidis and 9.2 % in A. gossypii. The development time of L. testaceipes in R. maidis and A. gossypii was 10.2 and 10.1 days, and the sex ratio of 0.71 and 0.66, respectively. The female of L. testaceipes had a fecundity of 498.8 eggs in R. maidis and 327.8 eggs in A. gossypii. The growth parameters the L. testaceipes in R. maidis and A. gossypii were, respectively R o = 205.38 and 164.08 females; r m = 0.449 and 0.431 females/females/day; λ= 1.57 and 1.54 females/day; T= 11.86 and 11.83 days and TD= 10.78 and 11.27 days. L. testaceipes showed great growth potential on both aphid hosts. R. maidis could be a suitable host for proposals of mass-rearing and open rearing system using L. testaceipes. (author)

  10. Round Spermatid Injection Rescues Female Lethality of a Paternally Inherited Xist Deletion in Mouse.

    Directory of Open Access Journals (Sweden)

    Federica Federici

    2016-10-01

    Full Text Available In mouse female preimplantation embryos, the paternal X chromosome (Xp is silenced by imprinted X chromosome inactivation (iXCI. This requires production of the noncoding Xist RNA in cis, from the Xp. The Xist locus on the maternally inherited X chromosome (Xm is refractory to activation due to the presence of an imprint. Paternal inheritance of an Xist deletion (XpΔXist is embryonic lethal to female embryos, due to iXCI abolishment. Here, we circumvented the histone-to-protamine and protamine-to-histone transitions of the paternal genome, by fertilization of oocytes via injection of round spermatids (ROSI. This did not affect initiation of XCI in wild type female embryos. Surprisingly, ROSI using ΔXist round spermatids allowed survival of female embryos. This was accompanied by activation of the intact maternal Xist gene, initiated with delayed kinetics, around the morula stage, resulting in Xm silencing. Maternal Xist gene activation was not observed in ROSI-derived males. In addition, no Xist expression was detected in male and female morulas that developed from oocytes fertilized with mature ΔXist sperm. Finally, the expression of the X-encoded XCI-activator RNF12 was enhanced in both male (wild type and female (wild type as well as XpΔXist ROSI derived embryos, compared to in vivo fertilized embryos. Thus, high RNF12 levels may contribute to the specific activation of maternal Xist in XpΔXist female ROSI embryos, but upregulation of additional Xp derived factors and/or the specific epigenetic constitution of the round spermatid-derived Xp are expected to be more critical. These results illustrate the profound impact of a dysregulated paternal epigenome on embryo development, and we propose that mouse ROSI can be used as a model to study the effects of intergenerational inheritance of epigenetic marks.

  11. Population ecology of feral horses in an era of fertility control management

    Science.gov (United States)

    Ransom, J.I.

    2012-01-01

    Management of wildlife often requires intervention to regulate growth of populations that would otherwise become overabundant. Controlling fecundity using contraceptives has become an increasingly popular tool for attempting to manage locally overabundant wildlife species, but the population-level effects of such applications are largely unknown. Contraceptive treatments can produce unexpected feedbacks that act on births, survival, immigration, and emigration. Such feedbacks may considerably influence our ability to regulate populations using fertility control. I followed feral horses (Equus caballus) in three intensively managed populations to assess longitudinal treatment effects on demography. The transient contraceptive porcine zona pellucida (PZP) produced longer duration of infertility than intended. Repeated PZP vaccinations of females extended the duration of infertility far beyond the targeted management period, with time to first post-treatment parturition increasing 411days for every annual inoculation received. When these animals did conceive and give birth, parturition was later in the year and temporally asynchronous with forage abundance. An average of 30% (range=11–77%) of females were contracepted annually during the treatment period in all three populations and apparent annual population growth rate was 4–9% lower in the post-treatment years as compared to pretreatment years. Population growth was positive, however, and increased steadily every year that a management removal did not occur. The observed number of births was 33% fewer than the expected number of births, based on number of treated females, individual efficacy of treatment, and number of untreated females and their age-specific fecundity rates. Only half of this difference was explained by the apparent residual effect of treatment. Birth rate in the youngest untreated females (age 2–5 years old) was reduced in years when their conspecifics were treated, enhancing the effects of

  12. Exposure to bisphenol A in young adult mice does not alter ovulation but does alter the fertilization ability of oocytes

    International Nuclear Information System (INIS)

    Moore-Ambriz, Teresita Rocio; Acuña-Hernández, Deyanira Guadalupe; Ramos-Robles, Brenda; Sánchez-Gutiérrez, Manuel; Santacruz-Márquez, Ramsés; Sierra-Santoyo, Adolfo; Piña-Guzmán, Belem

    2015-01-01

    Follicle growth culminates in ovulation, which allows for the expulsion of fertilizable oocytes and the formation of corpora lutea. Bisphenol A (BPA) is present in many consumer products, and it has been suggested that BPA impairs ovulation; however, the underlying mechanisms are unknown. Therefore, this study first evaluated whether BPA alters ovulation by affecting folliculogenesis, the number of corpora lutea or eggs shed to the oviduct, ovarian gonadotropin responsiveness, hormone levels, and estrous cyclicity. Because it has been suggested (but not directly confirmed) that BPA exerts toxic effects on the fertilization ability of oocytes, a second aim was to evaluate whether BPA impacts the oocyte fertilization rate using an in vitro fertilization assay and mating. The possible effects on early zygote development were also examined. Young adult female C57BL/6J mice (39 days old) were orally dosed with corn oil (vehicle) or 50 μg/kg bw/day BPA for a period encompassing the first three reproductive cycles (12–15 days). BPA exposure did not alter any parameters related to ovulation. Moreover, BPA exposure reduced the percentage of fertilized oocytes after either in vitro fertilization or mating, but it did not alter the zygotic stages. The data indicate that exposure to the reference dose of BPA does not impact ovulation but that it does influence the oocyte quality in terms of its fertilization ability. - Highlights: • Bisphenol A targets the fertilization ability of oocytes. • Bisphenol A does not alter ovulation. • Young adult females may be susceptible to the effects of bisphenol A on fertilization.

  13. Exposure to bisphenol A in young adult mice does not alter ovulation but does alter the fertilization ability of oocytes

    Energy Technology Data Exchange (ETDEWEB)

    Moore-Ambriz, Teresita Rocio; Acuña-Hernández, Deyanira Guadalupe; Ramos-Robles, Brenda [Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (Cinvestav-IPN), Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, México D.F. 07360, México (Mexico); Sánchez-Gutiérrez, Manuel [Área Académica de Medicina, Instituto de Ciencias de la Salud, Universidad Autónoma del Estado de Hidalgo, Pachuca, Hidalgo 42000, México (Mexico); Santacruz-Márquez, Ramsés; Sierra-Santoyo, Adolfo [Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (Cinvestav-IPN), Av. Instituto Politécnico Nacional 2508, Col. San Pedro Zacatenco, México D.F. 07360, México (Mexico); Piña-Guzmán, Belem [Instituto Politécnico Nacional-UPIBI, México D.F. 07738, México (Mexico); and others

    2015-12-15

    Follicle growth culminates in ovulation, which allows for the expulsion of fertilizable oocytes and the formation of corpora lutea. Bisphenol A (BPA) is present in many consumer products, and it has been suggested that BPA impairs ovulation; however, the underlying mechanisms are unknown. Therefore, this study first evaluated whether BPA alters ovulation by affecting folliculogenesis, the number of corpora lutea or eggs shed to the oviduct, ovarian gonadotropin responsiveness, hormone levels, and estrous cyclicity. Because it has been suggested (but not directly confirmed) that BPA exerts toxic effects on the fertilization ability of oocytes, a second aim was to evaluate whether BPA impacts the oocyte fertilization rate using an in vitro fertilization assay and mating. The possible effects on early zygote development were also examined. Young adult female C57BL/6J mice (39 days old) were orally dosed with corn oil (vehicle) or 50 μg/kg bw/day BPA for a period encompassing the first three reproductive cycles (12–15 days). BPA exposure did not alter any parameters related to ovulation. Moreover, BPA exposure reduced the percentage of fertilized oocytes after either in vitro fertilization or mating, but it did not alter the zygotic stages. The data indicate that exposure to the reference dose of BPA does not impact ovulation but that it does influence the oocyte quality in terms of its fertilization ability. - Highlights: • Bisphenol A targets the fertilization ability of oocytes. • Bisphenol A does not alter ovulation. • Young adult females may be susceptible to the effects of bisphenol A on fertilization.

  14. Prevalence of child marriage and its effect on fertility and fertility-control outcomes of young women in India: a cross-sectional, observational study.

    Science.gov (United States)

    Raj, Anita; Saggurti, Niranjan; Balaiah, Donta; Silverman, Jay G

    2009-05-30

    Child marriage is a substantial barrier to social and economic development in India, and a primary concern for women's health. We assessed the prevalence of child marriage-ie, before 18 years of age-in young adult women in India, and the associations between child marriage and women's fertility and fertility-control outcomes. Data from the National Family Health Survey-3 (2005-06) were limited to a sample of Indian women aged 20-24 years (n=22 807), of whom 14 813 had been or were presently married (ever-married). Prevalence of child marriage was estimated for the whole sample. We used regression models adjusted for demographics, and models adjusted for demographics and duration of marriage to estimate odds ratios (ORs) for the associations between child marriage and both fertility and fertility-control outcomes, in the ever-married subsample. 44.5% of women aged 20-24 years were married before age 18 years, 22.6% were married before age 16 years, and 2.6% were married before age 13 years. Child marriage was significantly associated with no contraceptive use before first childbirth (adjusted OR 1.37 [95% CI 1.22-1.54]), high fertility (three or more births) (7.40 [6.45-8.50]), a repeat childbirth in less than 24 months (3.00 [2.74-3.29]), multiple unwanted pregnancies (2.36 [1.90-2.94]), pregnancy termination (1.48 [1.34-1.63]), and female sterilisation (6.68 [5.78-7.60]). The association between child marriage and high fertility, a repeat childbirth in less than 24 months, multiple unwanted pregnancies, pregnancy termination, and sterilisation all remained significant after controlling for duration of marriage. Increased enforcement of existing policies is crucial for prevention of child marriage. Improved family-planning education, access, and support are urgently needed for women married as children, their husbands, and their families to reduce the high fertility and poor fertility-control outcomes of this practice. US National Institutes of Health and Indian

  15. In utero bisphenol A exposure disrupts germ cell nest breakdown and reduces fertility with age in the mouse

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wei, E-mail: weiwang2@illinois.edu; Hafner, Katlyn S., E-mail: katlynhafner@gmail.com; Flaws, Jodi A., E-mail: jflaws@illinois.edu

    2014-04-15

    Bisphenol A (BPA) is a known reproductive toxicant in rodents. However, the effects of in utero BPA exposure on early ovarian development and the consequences of such exposure on female reproduction in later reproductive life are unclear. Thus, we determined the effects of in utero BPA exposure during a critical developmental window on germ cell nest breakdown, a process required for establishment of the finite primordial follicle pool, and on female reproduction. Pregnant FVB mice (F0) were orally dosed daily with tocopherol-striped corn oil (vehicle), diethylstilbestrol (DES; 0.05 μg/kg, positive control), or BPA (0.5, 20, and 50 μg/kg) from gestational day 11 until birth. Ovarian morphology and gene expression profiles then were examined in F1 female offspring on postnatal day (PND) 4 and estrous cyclicity was examined daily after weaning for 30 days. F1 females were also subjected to breeding studies with untreated males at three to nine months. The results indicate that BPA inhibits germ cell nest breakdown via altering expression of selected apoptotic factors. BPA also significantly advances the age of first estrus, shortens the time that the females remain in estrus, and increases the time that the females remain in metestrus and diestrus compared to controls. Further, F1 females exposed to low doses of BPA exhibit various fertility problems and have a significantly higher percentage of dead pups compared to controls. These results indicate that in utero exposure to low doses of BPA during a critical ovarian developmental window interferes with early ovarian development and reduces fertility with age. - Highlights: • In utero BPA exposure inhibits germ cell nest breakdown in female mouse offspring. • In utero BPA exposure alters expression of apoptosis regulators in the ovaries of mouse offspring. • In utero BPA exposure advances first estrus age and alters cyclicity in mouse offspring. • In utero BPA exposure causes various fertility problems in

  16. In utero bisphenol A exposure disrupts germ cell nest breakdown and reduces fertility with age in the mouse

    International Nuclear Information System (INIS)

    Wang, Wei; Hafner, Katlyn S.; Flaws, Jodi A.

    2014-01-01

    Bisphenol A (BPA) is a known reproductive toxicant in rodents. However, the effects of in utero BPA exposure on early ovarian development and the consequences of such exposure on female reproduction in later reproductive life are unclear. Thus, we determined the effects of in utero BPA exposure during a critical developmental window on germ cell nest breakdown, a process required for establishment of the finite primordial follicle pool, and on female reproduction. Pregnant FVB mice (F0) were orally dosed daily with tocopherol-striped corn oil (vehicle), diethylstilbestrol (DES; 0.05 μg/kg, positive control), or BPA (0.5, 20, and 50 μg/kg) from gestational day 11 until birth. Ovarian morphology and gene expression profiles then were examined in F1 female offspring on postnatal day (PND) 4 and estrous cyclicity was examined daily after weaning for 30 days. F1 females were also subjected to breeding studies with untreated males at three to nine months. The results indicate that BPA inhibits germ cell nest breakdown via altering expression of selected apoptotic factors. BPA also significantly advances the age of first estrus, shortens the time that the females remain in estrus, and increases the time that the females remain in metestrus and diestrus compared to controls. Further, F1 females exposed to low doses of BPA exhibit various fertility problems and have a significantly higher percentage of dead pups compared to controls. These results indicate that in utero exposure to low doses of BPA during a critical ovarian developmental window interferes with early ovarian development and reduces fertility with age. - Highlights: • In utero BPA exposure inhibits germ cell nest breakdown in female mouse offspring. • In utero BPA exposure alters expression of apoptosis regulators in the ovaries of mouse offspring. • In utero BPA exposure advances first estrus age and alters cyclicity in mouse offspring. • In utero BPA exposure causes various fertility problems in

  17. Genetics of Fertility Indicators Based on Behaviour and Progesterone in Milk

    DEFF Research Database (Denmark)

    Løvendahl, P; Chagunda, M; O'Connell, J

    2009-01-01

    Genetic selection for female is diffecult because current records based on AI information are biased from farmer's decisions and have low heritablity (h2 = 0.03). Automated on-farm progesterone based heat detection methods are becoming commercially available, as has eqipment based on behaviour...... oestrus and would enable improved genetic selection for fertility traits....

  18. Unrealized fertility: Fertility desires at the end of the reproductive career

    Directory of Open Access Journals (Sweden)

    John Casterline

    2017-01-01

    Full Text Available Background: 'Unrealized fertility' is a failure to achieve desired fertility. Unrealized fertility has been examined in low-fertility societies but, with the exception of research on infertility, has been neglected in research on non-Western societies. Objective: We conduct a multicountry investigation of one form of unrealized fertility, namely a reproductive career which ends with the woman desiring further children. Methods: We analyze 295,854 women aged 44‒48 in 252 surveys (DHS, RHS, PAP conducted in the period 1986-2015 in 78 countries. Two indicators of unrealized fertility are constructed: (i a comparison of ideal versus actual number of children; (ii the desire for another child. We estimate multilevel regressions with covariates at individual and aggregate levels. Results: Unrealized fertility is far more prevalent according to the first indicator than the second. It is more common among women with fewer living children and women whose first birth occurs after age 20, and it is distinctly higher in sub-Saharan Africa and lower in South Asia. The evidence on trend over the course of fertility transition is mixed: for the second indicator but not the first, the net effect is a reduction in the prevalence of unrealized fertility as fertility declines. Conclusions: Unrealized fertility occurs frequently in most societies and therefore deserves more rigorous research, especially on its consequences for emotional, social, economic, and demographic outcomes. Contribution: We provide the first comprehensive documentation of the prevalence of unrealized fertility across a broad set of contemporary non-Western societies.

  19. Nuclear lamins and peripheral nuclear antigens during fertilization and embryogenesis in mice and sea urchins

    Science.gov (United States)

    Schatten, G.; Schatten, H.; Simerly, C.; Maul, G. G.; Chaly, N.

    1985-01-01

    Nuclear structural changes during fertilization and embryogenesis in mice and sea urchins are traced using four antibodies. The oocytes from virgin female mice, morulae and blastocytes from mated females, and gametes from the sea urchin Lytechnius variegatis are studied using mouse monoclonal antibodies to nuclear lamin A/C, monoclonal antibody to P1, human autoimmune antibodies to lamin A/C, and to lamin B. The mouse fertilization data reveal no lamins on the oocyte; however, lamins are present on the pronuclei, and chromosomes are found on the oocytes and pronuclei. It is detected that on the sea urchin sperm the lamins are reduced to acrosomal and centriolar fossae and peripheral antigens are around the sperm nucleus. The mouse sperm bind lamin antibodies regionally and do not contain antigens. Lamins and antigens are observed on both pronuclei and chromosomes during sea urchin fertilization. Mouse embryogenesis reveals that lamin A/C is not recognized at morula and blastocyst stages; however, lamin B stains are retained. In sea urchin embryogenesis lamin recognition is lost at the blastrula, gastrula, and plutei stages. It is noted that nuclear lamins lost during spermatogenesis are restored at fertilization and peripheral antigens are associated with the surface of chromosomes during meiosis and mitosis and with the periphery of the pronuclei and nuclei during interphase.

  20. The Effects of Chronic Ingestion of Mercuric Chloride on Fertility and Testosterone Levels in Male Sprague Dawley Rats

    Directory of Open Access Journals (Sweden)

    John C. Heath

    2012-01-01

    Full Text Available Although male infertility is well researched, the effects of inorganic mercury on male reproduction and fertility are less well known. Studies pertaining to mercury and male fertility identified reduced concentration of testosterone in the serum of male workers, a toxic influence on fertility of organic mercury compounds within concentrations at the workplace, and increased days to pregnancy. We evaluated the effect of chronic mercuric chloride (HgCl2 exposure in male rats on reproductive endpoints. Thirty-day old male Sprague Dawley rats (n=31 were exposed to 0.0, 1.0, or 2.0 mg/kg/day of HgCl2 via gavage. After 60 days exposure, they were housed with nonexposed females for 21 days. A survivor analysis revealed the exposed animals took longer to impregnate the females and had a lower rate of impregnation. Further statistical analysis revealed a lower correlation between testicular testosterone levels and days to impregnate, and also lower sperm counts in the epididymis head and body of the exposed males. The results indicate that HgCl2 exposure had significant adverse effects on male rat reproduction endpoints including fertility at a dose that was not clinically toxic.

  1. Biology and fertility life table of Agrotis ipsilon on artificial diet

    International Nuclear Information System (INIS)

    Bento, Flavia de Moura Manoel; Fortes, Priscila; Zerio, Neide Graciano; Parra, Jose Roberto Postali

    2007-01-01

    The objective of this work was to develop an artificial diet to rear Agrotis ipsilon in laboratory using biological parameters and fertility life table. The artificial diet was prepared with bean, casein, soybean protein, yeast and wheat germ as protein sources. The biological aspects duration and viability of larval and pupal stages, pupal weight, sex ratio, life span of adults, preoviposition period, egg laying capacity and fertility life table were evaluated. Six larval instars were observed comprising larval duration of 28,4 days and 93% of viability mean pupal duration of 12,4 days and viability of 96%. The total viability of the life cycle was 72%. The pupae weight was 387 mg for males and 484 mg for females. The sex ratio was 0,46 and the preoviposition period lasted one day and egg laying was 1,806 eggs per female. The net reproductive rate per generation and increase finite rate were 616,9 and 1,14, respectively. Artificial diet is adequate for rearing A. ipsilon in laboratory. (author)

  2. Viable acrosome-intact human spermatozoa in the ejaculate as a marker of semen quality and fertility status

    DEFF Research Database (Denmark)

    Egeberg Palme, Dorte Louise; Rehfeld, Anders; Bang, Anne Kirstine

    2018-01-01

    STUDY QUESTION: Is it possible, in an unbiased and clinical relevant way, to determine the number of viable acrosome-intact human spermatozoa in ejaculates and to use this as a measure of fertility chances? SUMMARY ANSWER: Image cytometry enables easy and unbiased quantification of viable acrosome......-intact spermatozoa and it correlates with semen quality and fertility status. WHAT IS KNOWN ALREADY: The presence of the acrosome and its ability to respond to physiological inducers (e.g. progesterone) in the female reproductive tract at the appropriate time and place is required for fertilization. However......, the available assays are labor intensive and therefore not used clinically. STUDY DESIGN, SIZE, DURATION: Washed semen samples and capacitated swim-up fractions from volunteers were used to develop the assay. Subsequently washed ejaculates from patients in fertility treatment (n = 156), proven fertile men (n...

  3. A central role for P48/45 in malaria parasite male gamete fertility.

    NARCIS (Netherlands)

    Dijk, M.R. van; Janse, C.J.; Thompson, J.; Waters, A.P.; Braks, J.A.M.; Dodemont, H.J.; Stunnenberg, H.G.; Gemert, G.J.A. van; Sauerwein, R.W.; Eling, W.M.C.

    2001-01-01

    Fertilization and zygote development are obligate features of the malaria parasite life cycle and occur during parasite transmission to mosquitoes. The surface protein PFS48/45 is expressed by male and female gametes of Plasmodium falciparum and PFS48/45 antibodies prevent zygote development and

  4. Angiotensin-Converting Enzymes Play a Dominant Role in Fertility

    Directory of Open Access Journals (Sweden)

    Fan Jin

    2013-10-01

    Full Text Available According to the World Health Organization, infertility, associated with metabolic syndrome, has become a global issue with a 10%–20% incidence worldwide. An accumulating body of evidence has shown that the renin–angiotensin system is involved in the fertility problems observed in some populations. Moreover, alterations in the expression of angiotensin-converting enzyme-1, angiotensin-converting enzyme-2, and angiotensin-converting enzyme-3 might be one of the most important mechanisms underlying both female and male infertility. However, as a pseudogene in humans, further studies are needed to explore whether the abnormal angiotensin-converting enzyme-3 gene could result in the problems of human reproduction. In this review, the relationship between angiotensin-converting enzymes and fertile ability is summarized, and a new procedure for the treatment of infertility is discussed.

  5. Auxin Homeostasis in Arabidopsis Ovules Is Anther-Dependent at Maturation and Changes Dynamically upon Fertilization

    Directory of Open Access Journals (Sweden)

    Emma Larsson

    2017-10-01

    Full Text Available The plant hormone auxin is a vital component for plant reproduction as it regulates the development of both male and female reproductive organs, including ovules and gynoecia. Furthermore, auxin plays important roles in the development and growth of seeds and fruits. Auxin responses can be detected in ovules shortly after fertilization, and it has been suggested that this accumulation is a prerequisite for the developmental reprogramming of the ovules to seeds, and of the gynoecium to a fruit. However, the roles of auxin at the final stages of ovule development, and the sources of auxin leading to the observed responses in ovules after fertilization have remained elusive. Here we have characterized the auxin readout in Arabidopsis ovules, at the pre-anthesis, anthesis and in the immediate post-fertilization stages, using the R2D2 auxin sensor. In addition we have mapped the expression of auxin biosynthesis and conjugation genes, as well as that of auxin transporting proteins, during the same developmental stages. These analyses reveal specific spatiotemporal patterns of the different auxin homeostasis regulators. Auxin biosynthesis genes and auxin transport proteins define a pre-patterning of vascular cell identity in the pre-anthesis funiculus. Furthermore, our data suggests that auxin efflux from the ovule is restricted in an anther-dependent manner, presumably to synchronize reproductive organ development and thereby optimizing the chances of successful fertilization. Finally, de novo auxin biosynthesis together with reduced auxin conjugation and transport result in an enhanced auxin readout throughout the sporophytic tissues of the ovules soon after fertilization. Together, our results suggest a sophisticated set of regulatory cascades that allow successful fertilization and the subsequent transition of the female reproductive structures into seeds and fruits.

  6. Religiosity, gender attitudes and women’s labour market participation and fertility decisions in Europe

    NARCIS (Netherlands)

    Guetto, R.; Luijkx, R.; Scherer, S.

    2015-01-01

    The Second Demographic Transition (SDT) theory underlines the importance of changing values and attitudes to explain the trend toward low fertility and raising female labour market participation. We contribute to this debate comparing religiosity and gender attitudes over several European countries

  7. Utilization of modern contraceptives among female traders in Jos ...

    African Journals Online (AJOL)

    McRoy

    use of modern contraceptives has remained low despite the high level of awareness of the modern contraceptives among the female traders. Health education on the ... protecting women's health and rights, impacting upon fertility ..... India. The Internet Journal of World Health and. Societal Politics 2008;5. 16. Makumbi F ...

  8. Return to fertility after extended chemical castration with a GnRH antagonist

    International Nuclear Information System (INIS)

    Kostanski, Janusz W; Jiang, Ge; Dani, Bhas A; Murty, Santos B; Qiu, Wei; Schrier, Bruce; Thanoo, B C; DeLuca, Patrick P

    2001-01-01

    Antagonistic analogues of GnRH for the treatment of prostate cancer may be used clinically in persons for whom return to fertility after such treatment is important or desirable. The purpose of this study was, therefore, to evaluate the effects of a long term treatment with orntide, a GnRH antagonist, on testosterone levels and fertility in male rats. Two groups of male rats received either 120-day orntide microspheres (8.8 mg orntide/kg/120 days) or vehicle alone (control group). Serum orntide and testosterone levels in both groups were monitored at certain intervals for 9 months from the initiation of treatment. After recovery of normal serum testosterone levels in the treated animals, each rat was housed with two proven breeder, but drug-naive, females. All mates of treated rats achieved pregnancy as rapidly as the mates of control rats although two of the control rats did not sire a litter with either female and one sired only one litter. The mean size of the litters of treated (12.3 offspring per litter) and control (10.6 offspring per litter) were similar. All offspring were grossly normal morphologically and behaviorally during the time to weaning. These results suggest that lack of fertility due to testosterone suppression is reversible after cessation of treatment with this GnRH antagonist

  9. Return to fertility after extended chemical castration with a GnRH antagonist

    Directory of Open Access Journals (Sweden)

    Schrier Bruce

    2001-10-01

    Full Text Available Abstract Background Antagonistic analogues of GnRH for the treatment of prostate cancer may be used clinically in persons for whom return to fertility after such treatment is important or desirable. The purpose of this study was, therefore, to evaluate the effects of a long term treatment with orntide, a GnRH antagonist, on testosterone levels and fertility in male rats. Methods Two groups of male rats received either 120-day orntide microspheres (8.8 mg orntide/kg/120 days or vehicle alone (control group. Serum orntide and testosterone levels in both groups were monitored at certain intervals for 9 months from the initiation of treatment. After recovery of normal serum testosterone levels in the treated animals, each rat was housed with two proven breeder, but drug-naive, females. Results All mates of treated rats achieved pregnancy as rapidly as the mates of control rats although two of the control rats did not sire a litter with either female and one sired only one litter. The mean size of the litters of treated (12.3 offspring per litter and control (10.6 offspring per litter were similar. All offspring were grossly normal morphologically and behaviorally during the time to weaning. Conclusions These results suggest that lack of fertility due to testosterone suppression is reversible after cessation of treatment with this GnRH antagonist.

  10. Successful pregnancy outcome after fertility-sparing surgery and chemotherapy for dysgerminoma.

    Science.gov (United States)

    Shamim, Muhammad

    2010-09-01

    Ovarian dysgerminoma is a rare malignancy of the ovary. This is a case report of a 30-year-old female, presenting with a huge ovarian mass along with multiple gallstones; she was treated by fertility-sparing excision of the mass and cholecystectomy, followed by chemotherapy. She later had an uneventful pregnancy and delivered a healthy baby.

  11. On the relative effect of spawning asynchrony, sperm quantity and sperm quality on paternity under sperm competition in an external fertilizer

    Directory of Open Access Journals (Sweden)

    Torvald Blikra Egeland

    2015-07-01

    Full Text Available How much of a fitness benefit is obtained by dominant males of external fertilizers from releasing ejaculates in synchrony with female egg-release when engaging in sperm competition, and what is the most important sperm trait for paternity in these situations? The Arctic charr (Salvelinus alpinus is an external fertilizer experiencing intense male-male competition over reproductive opportunities including sperm competition. To compensate for their disadvantage the sneaker males, which often spawn out of synchrony with the female, produce more and faster sperm than the guarding males. We used controlled in vitro fertilization trials with experimentally produced dominant and subordinate, sneaker males to test what effect relative synchrony in gamete release, sperm quality (i.e., motility and velocity and sperm quantity have on a male’s fertilization success in pair-wise sperm competitions. When the sneaker males released ejaculates after the guarding male there was no overall difference in fertilization success. The quality (i.e., motility and velocity of a male’s sperm relative to that of the competing male was the best predictor of male fertilization success regardless of their mating tactic and spawning synchrony. The relative number of sperm cells also had an effect on fertilization success, but mainly when the dominant and sneaker male ejaculated synchronously. Our close imitation of natural sperm competition in charr shows that the sneaker males of external fertilizing species may fully compensate for their disadvantaged mating role by producing ejaculates of higher quality - an adjustment strangely not met by dominants.

  12. Peptide signalling during the pollen tube journey and double fertilization.

    Science.gov (United States)

    Qu, Li-Jia; Li, Ling; Lan, Zijun; Dresselhaus, Thomas

    2015-08-01

    Flowering seed plants (angiosperms) have evolved unique ways to protect their gametes from pathogen attack and from drying out. The female gametes (egg and central cell) are deeply embedded in the maternal tissues of the ovule inside the ovary, while the male gametes (sperm cells) are enclosed in the vegetative pollen tube cell. After germination of the pollen tube at the surface of papilla cells of the stigma the two immobile sperm cells are transported deep inside the sporophytic maternal tissues to be released inside the ovule for double fertilization. Angiosperms have evolved a number of hurdles along the pollen tube journey to prevent inbreeding and fertilization by alien sperm cells, and to maximize reproductive success. These pre-zygotic hybridization barriers require intensive communication between the male and female reproductive cells and the necessity to distinguish self from non-self interaction partners. General molecules such as nitric oxide (NO) or gamma-aminobutyric acid (GABA) therefore appear to play only a minor role in these species-specific communication events. The past 20 years have shown that highly polymorphic peptides play a leading role in all communication steps along the pollen tube pathway and fertilization. Here we review our current understanding of the role of peptides during reproduction with a focus on peptide signalling during self-incompatibility, pollen tube growth and guidance as well as sperm reception and gamete activation. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  13. Natural conception rates in subfertile couples following fertility awareness training.

    Science.gov (United States)

    Frank-Herrmann, P; Jacobs, C; Jenetzky, E; Gnoth, C; Pyper, C; Baur, S; Freundl, G; Goeckenjan, M; Strowitzki, T

    2017-04-01

    To analyze cumulative pregnancy rates of subfertile couples after fertility awareness training. A prospective observational cohort study followed 187 subfertile women, who had received training in self-observation of the fertile phase of the menstrual cycle with the Sensiplan method, for 8 months. The women, aged 21-47 years, had attempted to become pregnant for 3.5 years on average (range 1-8 years) before study entry. Amenorrhea, known tubal occlusion and severe male factor had been excluded. An additional seven women, who had initially been recruited, became pregnant during the cycle immediately prior to Sensiplan training: this is taken to be the spontaneous pregnancy rate per cycle in the cohort in the absence of fertility awareness training. The cumulative pregnancy rate of subfertile couples after fertility awareness training was 38% (95% CI 27-49%; 58 pregnancies) after eight observation months, which is significantly higher than the estimated basic pregnancy rate of 21.6% in untrained couples in the same cohort. For couples who had been seeking to become pregnant for 1-2 years, the pregnancy rate increased to 56% after 8 months. A female age above 35 (cumulative pregnancy rate 25%, p = 0.06), couples who had attempted to become pregnant for more than 2 years (cumulative pregnancy rate 17%, p conceiving naturally at some point. Training women to identify their fertile window in the menstrual cycle seems to be a reasonable first-line therapy in the management of subfertility.

  14. Labor force participation and fertility: a study of married women in Bangladesh.

    Science.gov (United States)

    Miah, M M; Mizan, A N

    1992-01-01

    Most researchers support the notion that a direct negative relationship exists between married women's labor force participation and fertility behavior, yet female employment shows no consistent, general relationship with declining fertility at individual and societal levels. Specific conditions under which employment lowers fertility are therefore explored for the case of Bangladesh. The economic, sociological, and world-system theoretical approaches to the relationship and empirical studies in developing countries including Bangladesh are reviewed. 1975-76 Bangladesh Fertility Survey data on births, deaths, nuptiality, and family planning knowledge and practice for 5772 currently married women of 6513 ever married women under 50 sampled are subjected to multivariate analysis for the study. Analysis revealed that women's modern and traditional occupation as well as higher and secondary education significantly lower their fertility, and that higher age, Islamic religion, use of modern contraceptives, and husband's occupation in transitional and modern sectors have significant positive effects on fertility. The correlation between higher fertility and contraceptive use may be due to women's delay in practicing family planning until reaching desired parity and/or high infant mortality driving women to cease practice in order to replace lost offspring. Future research should be conducted with larger samples and also consider occupations of both husbands and wives. Societal attitudes about women's education should be reformed in support of opening rural schools for women. With 90% of women residing in rural areas and women with traditional occupations having lower fertility, more traditional sector opportunities for women in cottage industry and agriculture production are also recommended, and would help balance skewed urban growth and hypertrophication of the tertiary sector. Finally, motivational efforts should be focused upon encouraging younger instead of older

  15. Species delimitation in asexual insects of economic importance: The case of black scale (Parasaissetia nigra, a cosmopolitan parthenogenetic pest scale insect.

    Directory of Open Access Journals (Sweden)

    Yen-Po Lin

    Full Text Available Asexual lineages provide a challenge to species delimitation because species concepts either have little biological meaning for them or are arbitrary, since every individual is monophyletic and reproductively isolated from all other individuals. However, recognition and naming of asexual species is important to conservation and economic applications. Some scale insects are widespread and polyphagous pests of plants, and several species have been found to comprise cryptic species complexes. Parasaissetia nigra (Nietner, 1861 (Hemiptera: Coccidae is a parthenogenetic, cosmopolitan and polyphagous pest that feeds on plant species from more than 80 families. Here, we implement multiple approaches to assess the species status of P. nigra, including coalescence-based analyses of mitochondrial and nuclear genes, and ecological niche modelling. Our results indicate that the sampled specimens of P. nigra should be considered to comprise at least two ecotypes (or "species" that are ecologically differentiated, particularly in relation to temperature and moisture. The presence of more than one ecotype under the current concept of P. nigra has implications for biosecurity because the geographic extent of each type is not fully known: some countries may currently have only one of the biotypes. Introduction of additional lineages could expand the geographic extent of damage by the pest in some countries.

  16. The psychological impact of infertility and fertility treatment on the male partner.

    Science.gov (United States)

    Dooley, Maeve; Dineen, Tim; Sarma, Kiran; Nolan, Aonghus

    2014-09-01

    This paper reports the findings of two studies that examined factors predicting infertility distress in male partners within couples with an infertility diagnosis and where the couple was receiving fertility treatment. A cross-sectional design was implemented using a questionnaire battery (The questionnaire battery comprised an inventory of four different standardised questionnaires compiled together into one booklet) compiled from earlier theory-building qualitative research conducted by the authors. Infertility related distress was examined in relation to a number of psychosocial variables including relationship dynamics, self-esteem, current mental health and attitudes towards idealised masculinity. The questionnaire battery was completed by 167 men undergoing or consulting for fertility treatment. Participants were recruited through Irish fertility clinics (Study 1, n = 111) and through an online survey (Study 2, n = 55). Regression analyses identified four variables that predicted variance in infertility distress in both studies: 'Attitude towards idealised masculinity', 'Mental health', 'Relationship satisfaction' and 'Self-esteem'. This finding was found to be robust having controlled for age, time since diagnosis, number of attempts at treatment and diagnostic category (male factor, female factor or mixed factor infertility). ConclusiON: Recommendations for fertility clinics and mental health professionals should be made in relation to managing infertility distress and supporting couples during fertility treatment.

  17. Infertility in reproductive-age female cancer survivors.

    Science.gov (United States)

    Levine, Jennifer M; Kelvin, Joanne Frankel; Quinn, Gwendolyn P; Gracia, Clarisa R

    2015-05-15

    Improved survival rates among reproductive-age females diagnosed with cancer have increased the focus on long-term quality of life, including maintenance of the ability to conceive biological children. Cancer-directed therapies such as high-dose alkylating agents and radiation to the pelvis, which deplete ovarian reserve, radiation to the brain, which affects the hypothalamic-pituitary-gonadal axis, and surgical resection of reproductive structures can decrease the likelihood of having biological children. Standard fertility preservation strategies such as embryo and oocyte cryopreservation before the onset of therapy offer the opportunity to conserve fertility, but they may not be feasible because of the urgency to start cancer therapy, financial limitations, and a lack of access to reproductive endocrinologists. Ovarian tissue freezing is considered experimental, with limited data related to pregnancies, but it minimizes treatment delay. Studies evaluating gonadotropin-releasing hormone analogues have had mixed results, although a recent randomized, prospective study in women with breast cancer demonstrated a protective effect. Fertility preservation programs are increasingly being developed within cancer programs. In this article, we describe risks to infertility and options for preservation, raise psychosocial and ethical issues, and propose elements for establishing an effective fertility preservation program. © 2015 American Cancer Society.

  18. Desired Numbers of Children, Fertility Preferences and Related Factors among Couples Who Referred to Pre-Marriage Counseling in Alborz Province, Iran.

    Science.gov (United States)

    Lotfi, Razieh; Rajabi Naeeni, Masoumeh Rajabi Naeeni; Rezaei, Nasrin; Farid, Malihe; Tizvir, Afsoon

    2017-10-01

    The Islamic Republic of Iran has experienced a dramatic decrease in fertility rates in the past three decades. One of the main issues in the field of fertility is the couple's preferences and the desire to bear children. This study aimed to determine desired number of children, fertility preference, and related factors among people referring pre-marriage counseling to clarify their presumed behavior in case of fertility. This study was a descriptive analytic cross-sectional survey, conducted during 8 months. The participants were 300 couples came to pre-marriage counseling centers of two health centers of Karaj and asked to complete a 22 items questionnaire about of demographic characteristics, participants' interest, preference about fertility, and economic situation. Majority of the males were between the ages of 20-30 years (66.6%) while majority of the females were below 25 years of age (57%). About 17 percent of men and 22.3 percent of women stated that they want to have 1 child and equally 52.7 percent of men and 52.7 percent of women wanted to have 2 children. The only factor that contributed to the female participant's decision for a desirable number of children was the number of siblings that they have. In male participants with an increasing age at marriage and aspiration for higher educational level, the time interval between marriage and the birth of the first child has increased. There was a convergence in desired number of children in male and female participants. Majority of the participants express their desire to have only one or two children in future but in considering the fact that what one desires does not always come into reality, the risk of reduced fertility is generally present in the community. Appropriate policies should be implemented in order to create a favorable environment for children. Copyright© by Royan Institute. All rights reserved.

  19. Revisiting "The fertilization fairytale:" an analysis of gendered language used to describe fertilization in science textbooks from middle school to medical school

    Science.gov (United States)

    Campo-Engelstein, Lisa; Johnson, Nadia L.

    2014-03-01

    Emily Martin's (Signs J Women Cult Soc 16(31):485-501, 1991) article, "The Egg and the Sperm: How Science Has Constructed a Romance Based on Stereotypical Male-Female Roles," was published in Signs over 20 years ago. In this groundbreaking article, she discusses how gender roles are often projected onto reproductive biology, leading to the portrayal of eggs as passive and sperm as active. We were interested in seeing if many of her findings are still relevant today. We analyzed science textbooks from the middle school to the medical school level to determine if fertilization in human reproduction is described in gender-biased language regarding the sentence structure, amount of information provided for female and male processes/parts, and neutrality in describing female and male processes/parts. Although there has been much improvement, there is still a long way to go. Sexist language in scientific textbooks is troubling because it negatively affects both female and male students and undermines teachers' ability to teach in an accurate and gender-neutral way.

  20. The fertility transition in Cuba and the Federal Republic of Korea: the impact of organised family planning.

    Science.gov (United States)

    Noble, J; Potts, M

    1996-04-01

    South Korea and Cuba are dissimilar in religion, economy, culture and attitudes toward premarital sexual relations. In 1960, Korea instituted a national family planning programme to combat rapid population growth. Cuba explicitly rejected Malthusian policies, but made family planning universally available in 1974 in response to health needs. Both countries have undergone rapid fertility declines and today have less than replacement level fertility. Both countries have also used a similar mixture of methods, including a high prevalence of female sterilisation. Abortion has played a major role in the fertility decline of both countries, rising in the first half of the fertility transition and then falling, although remaining a significant variable in the second half. It is concluded that access to contraception, voluntary sterilisation, and safe abortion has a direct impact on fertility and has been associated with a rapid fall in family size in two very different countries.

  1. Cohort fertility decline in low fertility countries: Decomposition using parity progression ratios

    Directory of Open Access Journals (Sweden)

    Krystof Zeman

    2018-02-01

    Full Text Available Background: The long-term decline in cohort fertility in highly developed countries has been widely documented. However, no systematic analysis has investigated which parity contributed most to the fertility decline to low and very low levels. Objective: We examine how the contribution of changing parity progression ratios varied across cohorts, countries, and broader regions in Europe, North America, Australia, and East Asia. We pay special attention to countries that reached very low completed cohort fertility, below 1.75 children per woman. Methods: Using population censuses and large-scale surveys for 32 low fertility countries, we decompose the change in completed cohort fertility among women born between 1940 and 1970. The decomposition method takes into account the sequential nature of childbearing as a chain of transitions from lower to higher parities. Results: Among women born between 1940 and 1955, the fertility decline was mostly driven by reductions in the progression ratios to third and higher-order births. By contrast, among women born between 1955 and 1970, changes in fertility showed distinct regional patterns: in Central and Eastern Europe they were fuelled by falling second-birth rates, whereas in the German-speaking countries, Southern Europe, and East Asia decreases in first-birth rates played the major role. Conclusions: Pathways to low and very low fertility show distinct geographical patterns, which reflect the diversity of the cultural, socioeconomic, and institutional settings of low fertility countries. Contribution: Our study highlights the importance of analysing parity-specific components of fertility in order to understand fertility change and variation. We demonstrate that similar low levels of completed cohort fertility can result from different combinations of parity-specific fertility rates.

  2. The long-term prognosis for live birth in couples initiating fertility treatments

    DEFF Research Database (Denmark)

    Malchau, S. S.; Henningsen, A. A.; Loft, A.

    2017-01-01

    -26% in women ≥40 years, overall, 14% of couples conceived naturally and one-third of couples starting treatments with intrauterine insemination delivered from that treatment. WHAT IS KNOWN ALREADY: Few studies report success rates in fertility treatments across a couple's complete fertility treatment history......STUDY QUESTION: What are the long-term chances of having a child for couples starting fertility treatments and how many conceive with ART, IUI and without treatment? SUMMARY ANSWER: Total 5-year live birthrates were strongly influenced by female age and ranged from 80% in women under 35...... years (N = 3553), 35-39 years (N = 1156) and ≥40 years (N = 451), a total of 64%, 49% and 16% had a live birth due to treatment, respectively. Additionally, in women aged years, 35-39 years and ≥40 years, 16%, 11% and 10% delivered after natural conception, yielding total 5-year birthrates of 80...

  3. First production of larvae using cryopreserved sperm: Effects of preservation temperature and cryopreservation on European eel sperm fertilization capacity

    DEFF Research Database (Denmark)

    Asturiano, J.F.; Sørensen, Sune Riis; Perez, L.

    2016-01-01

    Sperm cryopreservation is a useful tool in captive fish reproduction management, that is to synchronize gamete production, especially in the case of species as the European eel, where the time of female spawning readiness is unpredictable. Several protocols to cryopreserve sperm of this species....... Fertilization of two egg batches was attempted. Diluted sperm caused a similar percentage of fertilized eggs and a similar number of embryos and larvae, independently of storage temperature (4 or 20°C). The cryopreserved sperm resulted in a lower percentage of fertilized eggs, but embryos developed and a few...... larvae ('cryolarvae') were obtained 55 h after fertilization in one of the two egg batches. This result evidences that the tested cryopreservation protocol is applicable for eel reproduction management, although improvements will be required to enhance fertilization success...

  4. Fertility awareness and attitudes towards parenthood among Danish university college students.

    Science.gov (United States)

    Sørensen, Nina Olsén; Marcussen, Signe; Backhausen, Mette Grønbæk; Juhl, Mette; Schmidt, Lone; Tydén, Tanja; Hegaard, Hanne Kristine

    2016-12-13

    Postponing parenthood has steadily increased during the past decades in Western countries. This trend has affected the size of families in the direction of fewer children born per couple. In addition, higher maternal age is associated with an increased risk of pregnancy-related complications such as prematurity and foetal death, while higher paternal age increases the risk of miscarriage and affects time-to-pregnancy. Hence, understanding the circumstances and reflections that influence the decision is greatly needed and little is known about potential gender difference influencing the choice. The aim was to investigate attitudes towards parenthood, intentions for childbirth and knowledge about fertility issues among men and women. We conducted a cross-sectional study based on a validated 49-item questionnaire among students, who attended selected mandatory lectures at a Danish university college in February to April 2016. The participation rate was 99%, and 517 completed the questionnaire. Though the majority of all participants wished to have children in the future (>86%), there was significant difference between the genders (p = 0.002). Women rated having children to be more important than men did (p fertility issues was similar between genders including poor knowledge about the age-related decline in female fertility. While women found it more important to have children before being 'too old' (p = 0.04), still more than 40% of all respondents intended to have their last child after the age of 35 years. For both genders the most important prerequisite for parenthood was having a partner to share responsibility with. Perceived or experienced life changes related to parenthood were generally positive such as personal development. The majority of respondents wished to have children, but many desired to have these after the biological decline in female fertility. The moderate knowledge level among both genders uncovered in this study is of concern. Future

  5. Fertility awareness online: the efficacy of a fertility education website in increasing knowledge and changing fertility beliefs.

    Science.gov (United States)

    Daniluk, J C; Koert, E

    2015-02-01

    How effective is online education in increasing knowledge of fertility and assisted reproductive technologies (ART), and changing beliefs about the timing of parenthood? Exposure to an online educational intervention resulted in immediate changes in participants' beliefs about the ideal timing of parenthood, and a significant increase in their knowledge of fertility and ART treatments and options; most of these changes were not sustained over time, particularly for men. Research has identified significant gaps in men's and women's knowledge of fertility and ART, contributing to the trend to delay childbearing. Effective educational programs need to be developed, to support informed fertility and child-timing decisions. Pre-post intervention study of 199 currently childless men and women, and a 6-month follow-up of 110 of these participants. One hundred and ninety-nine childless participants between the ages of 18 and 35 were asked to complete 4 beliefs and 22 knowledge questions prior to, and immediately after, reading 10 online posts related to: fertility testing and preservation, fertility history and lifespan, the effects of health and fitness on fertility, and assisted reproduction. Six months later, 110 of the original sample repeated the 26-item survey. Participants' fertility and ART knowledge scores increased significantly immediately after the intervention, as did their confidence in their fertility and ART knowledge. Participants' beliefs about the ideal and latest age a woman or man should consider producing a child decreased. However, 6 months later, participants' beliefs and knowledge levels largely returned to their pre-intervention levels, particularly for the men in the study. The sample size and the recruitment methods may limit the generalizability of these findings. Previous studies have demonstrated the short-term efficacy of online educational approaches to increase fertility knowledge and support informed family planning decisions. Web

  6. Effects of ovarian fluid and genetic differences on sperm performance and fertilization success of alternative reproductive tactics in Chinook salmon.

    Science.gov (United States)

    Lehnert, S J; Butts, I A E; Flannery, E W; Peters, K M; Heath, D D; Pitcher, T E

    2017-06-01

    In many species, sperm velocity affects variation in the outcome of male competitive fertilization success. In fishes, ovarian fluid (OF) released with the eggs can increase male sperm velocity and potentially facilitate cryptic female choice for males of specific phenotypes and/or genotypes. Therefore, to investigate the effect of OF on fertilization success, we measured sperm velocity and conducted in vitro competitive fertilizations with paired Chinook salmon (Oncorhynchus tshawytscha) males representing two alternative reproductive tactics, jacks (small sneaker males) and hooknoses (large guarding males), in the presence of river water alone and OF mixed with river water. To determine the effect of genetic differences on fertilization success, we genotyped fish at neutral (microsatellites) and functional [major histocompatibility complex (MHC) II ß1] markers. We found that when sperm were competed in river water, jacks sired significantly more offspring than hooknoses; however, in OF, there was no difference in paternity between the tactics. Sperm velocity was significantly correlated with paternity success in river water, but not in ovarian fluid. Paternity success in OF, but not in river water alone, was correlated with genetic relatedness between male and female, where males that were less related to the female attained greater paternity. We found no relationship between MHC II ß1 divergence between mates and paternity success in water or OF. Our results indicate that OF can influence the outcome of sperm competition in Chinook salmon, where OF provides both male tactics with fertilization opportunities, which may in part explain what maintains both tactics in nature. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  7. Fertility and Population Policy

    OpenAIRE

    Ouedraogo, Abdoulaye; Tosun, Mehmet S.; Yang, Jingjing

    2018-01-01

    There have been significant changes in both the fertility rates and fertility perception since 1970s. In this paper, we examine the relationship between government policies towards fertility and the fertility trends. Total fertility rate, defined as the number of children per woman, is used as the main fertility trend variable. We use panel data from the United Nations World Population Policies database, and the World Bank World Development Indicators for the period 1976 through 2013. We find...

  8. Identification of Common Genetic Variants Influencing Spontaneous Dizygotic Twinning and Female Fertility

    Science.gov (United States)

    Mbarek, Hamdi; Steinberg, Stacy; Nyholt, Dale R.; Gordon, Scott D.; Miller, Michael B.; McRae, Allan F.; Hottenga, Jouke Jan; Day, Felix R.; Willemsen, Gonneke; de Geus, Eco J.; Davies, Gareth E.; Martin, Hilary C.; Penninx, Brenda W.; Jansen, Rick; McAloney, Kerrie; Vink, Jacqueline M.; Kaprio, Jaakko; Plomin, Robert; Spector, Tim D.; Magnusson, Patrik K.; Reversade, Bruno; Harris, R. Alan; Aagaard, Kjersti; Kristjansson, Ragnar P.; Olafsson, Isleifur; Eyjolfsson, Gudmundur Ingi; Sigurdardottir, Olof; Iacono, William G.; Lambalk, Cornelis B.; Montgomery, Grant W.; McGue, Matt; Ong, Ken K.; Perry, John R.B.; Martin, Nicholas G.; Stefánsson, Hreinn; Stefánsson, Kari; Boomsma, Dorret I.

    2016-01-01

    Spontaneous dizygotic (DZ) twinning occurs in 1%–4% of women, with familial clustering and unknown physiological pathways and genetic origin. DZ twinning might index increased fertility and has distinct health implications for mother and child. We performed a GWAS in 1,980 mothers of spontaneous DZ twins and 12,953 control subjects. Findings were replicated in a large Icelandic cohort and tested for association across a broad range of fertility traits in women. Two SNPs were identified (rs11031006 near FSHB, p = 1.54 × 10−9, and rs17293443 in SMAD3, p = 1.57 × 10−8) and replicated (p = 3 × 10−3 and p = 1.44 × 10−4, respectively). Based on ∼90,000 births in Iceland, the risk of a mother delivering twins increased by 18% for each copy of allele rs11031006-G and 9% for rs17293443-C. A higher polygenic risk score (PRS) for DZ twinning, calculated based on the results of the DZ twinning GWAS, was significantly associated with DZ twinning in Iceland (p = 0.001). A higher PRS was also associated with having children (p = 0.01), greater lifetime parity (p = 0.03), and earlier age at first child (p = 0.02). Allele rs11031006-G was associated with higher serum FSH levels, earlier age at menarche, earlier age at first child, higher lifetime parity, lower PCOS risk, and earlier age at menopause. Conversely, rs17293443-C was associated with later age at last child. We identified robust genetic risk variants for DZ twinning: one near FSHB and a second within SMAD3, the product of which plays an important role in gonadal responsiveness to FSH. These loci contribute to crucial aspects of reproductive capacity and health. PMID:27132594

  9. Direct observation of female mating frequency using time-lapse photography

    NARCIS (Netherlands)

    Kuijper, Bram; Morrow, Edward H.

    2009-01-01

    One basic condition of postmating sexual selection is that females mate more than once before fertilizing their ova. Knowledge of the frequency and extent of multiple mating in a given population or species is therefore important in order to fully understand the potential for sexual selection, in

  10. Assessing genetic variability in male sterile and low fertile citrus ...

    African Journals Online (AJOL)

    Yomi

    2012-01-24

    Jan 24, 2012 ... male sterile types, with old scattered resources; Iran has obvious diversity of citrus materials. ... From each accession, four young leaves were taken and total genomic DNA was ..... sexual reproduction and recombination are disabled in detecting such mutations in asexually propagated species. Therefore ...

  11. The Fertility Problem Inventory: measuring perceived infertility-related stress.

    Science.gov (United States)

    Newton, C R; Sherrard, W; Glavac, I

    1999-07-01

    To develop a reliable, valid instrument to evaluate perceived infertility-related stress. Prospective study. University-affiliated teaching hospital. Consecutively referred patients (1,153 women and 1,149 men) seen for infertility treatment. None. Participants' infertility-related stress was assessed by written questionnaire using the Fertility Problem Inventory. Current levels of anxiety, depression, and marital satisfaction also were determined. Women described greater global stress than men and higher specific stress in terms of social concerns, sexual concerns, and need for parenthood. Both men and women facing male infertility reported higher global stress and more social and sexual concerns than men and women experiencing female infertility. Social, sexual, and relationship concerns related to infertility were more effective predictors of depression and marital dissatisfaction than expressed needs for parenthood or attitudes toward child-free living. The Fertility Problem Inventory provides a reliable measure of perceived infertility-related stress and specific information on five separate domains of patient concern. Patterns of infertility-related stress differed depending on gender, fertility history, and infertility diagnosis. Among patients receiving treatment, social, sexual, and relationship concerns appear central to current distress. Counseling interventions that target these domains appear likely to offer maximal therapeutic benefit.

  12. The focus of women in The American Fertility Society.

    Science.gov (United States)

    Haseltine, F P; Wentz, A C

    1984-09-01

    This article reports survey responses from 71 female members of the American Fertility Society during the Society's 1984 annual meeting. Survey questions concern 1) demographic factors such as rank, degree, title, address, and number of children, 2) field of specialization and research interests, and 3) what the Society can do for its meeting participants. The typical respondent is a physician living in the Eastern United States and employed as an assistant professor in an academic setting. In vitro fertilization is the greatest area of interest, followed by general practice, endocrine and male infertility, contraception, and fertility surgery. Survey responses show that women are interested in 1) networking, 2) increased visibility at professional meetings, 3) information about research possibilities and grants, 4) child care provision at Society meetings, and 5) more basic science and physiology oriented presentions in the program. In response to networking interests, the Society will make available information from the surveyed members. Since 16% of respondents have a PH.D., and 77% are employed in academics, the Society should consider more basic presentations. The need for day care indicates changes in Society membership. The Society plans to conduct similar surveys on a regular basis.

  13. The Effect of Childhood Family Size on Fertility in Adulthood: New Evidence From IV Estimation.

    Science.gov (United States)

    Cools, Sara; Kaldager Hart, Rannveig

    2017-02-01

    Although fertility is positively correlated across generations, the causal effect of children's experience with larger sibships on their own fertility in adulthood is poorly understood. With the sex composition of the two firstborn children as an instrumental variable, we estimate the effect of sibship size on adult fertility using high-quality data from Norwegian administrative registers. Our study sample is all firstborns or second-borns during the 1960s in Norwegian families with at least two children (approximately 110,000 men and 104,000 women). An additional sibling has a positive effect on male fertility, mainly causing them to have three children themselves, but has a negative effect on female fertility at the same margin. Investigation into mediators reveals that mothers of girls shift relatively less time from market to family work when an additional child is born. We speculate that this scarcity in parents' time makes girls aware of the strains of life in large families, leading them to limit their own number of children in adulthood.

  14. Sperm competition, but not major histocompatibility divergence, drives differential fertilization success between alternative reproductive tactics in Chinook salmon.

    Science.gov (United States)

    Lehnert, S J; Helou, L; Pitcher, T E; Heath, J W; Heath, D D

    2018-01-01

    Post-copulatory sexual selection processes, including sperm competition and cryptic female choice (CFC), can operate based on major histocompatibility (MH) genes. We investigated sperm competition between male alternative reproductive tactics [jack (sneaker) and hooknose (guard)] of Chinook salmon (Oncorhynchus tshawytscha). Using a full factorial design, we examined in vitro competitive fertilization success of paired jack and hooknose males at three time points after sperm activation (0, 15 and 60 s) to test for male competition, CFC and time effects on male fertilization success. We also examined egg-mediated CFC at two MH genes by examining both the relationship between competitive fertilization success and MH divergence as well as inheritance patterns of MH alleles in resulting offspring. We found that jacks sired more offspring than hooknose males at 0 s post-activation; however, jack fertilization success declined over time post-activation, suggesting a trade-off between sperm speed and longevity. Enhanced fertilization success of jacks (presumably via higher sperm quality) may serve to increase sneaker tactic competitiveness relative to dominant hooknose males. We also found evidence of egg-mediated CFC (i.e. female × male interaction) influencing competitive fertilization success; however, CFC was not acting on the MH genes as we found no relationship between fertilization success and MH II β 1 or MH I α 1 divergence and we found no deviations from Mendelian inheritance of MH alleles in the offspring. Our study provides insight into evolutionary mechanisms influencing variation in male mating success within alternative reproductive tactics, thus underscoring different strategies that males can adopt to attain success. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  15. The effect of celery (Apium graveolens L.) on fertility: A systematic review.

    Science.gov (United States)

    Kooti, Wesam; Moradi, Maryam; Peyro, Khadijeh; Sharghi, Maedeh; Alamiri, Fatima; Azami, Milad; Firoozbakht, Mohammad; Ghafourian, Mehri

    2017-10-06

    Background Fertility and infertility problems are among the complex issues in medicine. The use of herbal products in the treatment of fertility has been considered as an alternative to synthetic drugs. Celery containing known compounds can have an impact on the fertility rate. The aim of this study was to do a systematic review on conducted studies in conjunction with the celery and reproduction. Methods Required papers were searched from databases like Science direct, PubMed, Scopus, and Springer. Keywords used in this study were "Apium graveolens L.", "fertility", "reproductive system", "sperm", "testis", "delivery", "sexual hormone", "LH", "FSH", "testosterone", "semen", "male", and "female". Out of 238 collected articles (published in the period 1995 to 2015), 222 were excluded due to non-relevance and lack of access to the original article. Results The notable points were the different results seen by different researchers during different treatment periods or at different doses. Of the 16 studies reviewed in this study, 13 studies have mentioned the positive effect of celery on fertility, while three studies reported the inhibitory effects of this plant. Conclusions Celery can have protective effects against substances such as sodium valproate, propylene glycol, and diethyl phthalate causing damages to the testicular structure and spermatogenesis. In this regard, the doses used and the treatment time while using the plant must be accurately investigated. Since there are compounds such as apigenin, the celery can induce inhibitory effects on fertility in case of chronic use or high concentration.

  16. A frozen-thawed in vitro-matured bovine oocyte derived calf with normal growth and fertility.

    Science.gov (United States)

    Otoi, T; Yamamoto, K; Koyama, N; Tachikawa, S; Suzuki, T

    1996-08-01

    The growth and fertility of a female calf obtained from a frozen-thawed bovine oocyte was assessed. The birth weight of the calf was lower than the mean birth weight of calves from in vitro fertilized embryos (IVF-controls) and calves obtained by artificial insemination (AI-controls). The growth rate of the calf up to 6 months was slower than that of the IVF-controls, but similar to that of the AI-controls. When the calf developed into a heifer (200 kg), she was inseminated with frozen semen and 280 days later delivered a male calf. The chromosoms of this cow were normal. These findings suggest that the growth and fertility of the calf derived from the frozen oocyte are normal.

  17. Association of high fetuin-B concentrations in serum with fertilization rate in IVF: a cross-sectional pilot study.

    Science.gov (United States)

    Floehr, Julia; Dietzel, Eileen; Neulen, Josef; Rösing, Benjamin; Weissenborn, Ute; Jahnen-Dechent, Willi

    2016-03-01

    Is serum fetuin-B associated with the fertilization rate in in vitro fertilization (IVF)? Serum fetuin-B increased during IVF cycles when oocytes could be fertilized while remained unchanged in fertilization failure. Fetuin-B deficiency in mice causes premature zona pellucida hardening mediated by the zona protease ovastacin. Thus fetuin-B deficiency renders females infertile. We determined the human serum fetuin-B reference range, studying longitudinally, over the course of one month, five male and seven female volunteers without hormone treatment and four female volunteers on varying hormonal contraception. We sampled blood and determined serum fetuin-B, luteinizing hormone (LH), estradiol (E2) and progesterone (P4). In addition, we determined serum fetuin-B and estradiol in eight women undergoing intracytoplasmatic sperm injection (ICSI, nine ICSI cycles) and 19 women undergoing IVF (21 IVF cycles) after ovarian stimulation with recombinant human follicular stimulating hormone (rFSH) and/or a combined medication of FSH and LH. At least three blood samples were analyzed in each cycle. We compared serum fetuin-B and follicular fluid fetuin-B in nine patients by measuring follicular fetuin-B in pooled follicular fluid, and in fluid obtained from individual follicles. Samples were drawn from January 2012 to March 2014. All volunteers and patients gave informed consent. Fetuin-B was measured employing a commercial sandwich enzyme-linked immunosorbent assay. Serum fetuin-B was determined as duplicates in 5 male (34 ± 14.6 years) and 11 female volunteers (29.4 ± 4.1 years) as well as in female volunteers on hormonal contraception (30.0 ± 6.5 years). The duplicate standard deviation was 4.0 ± 2.3%. The contraceptive drugs were mono or combined preparations containing 0-0.03 mg ethinyl estradiol, and 0.15-3.0 mg of various progestins. In addition, serum fetuin-B was determined as triplicates in 27 female patients undergoing conventional IVF (19) or ICSI (8). The

  18. Male songbirds provide indirect parental care by guarding females during incubation

    Science.gov (United States)

    Fedy, B.C.; Martin, T.E.

    2009-01-01

    Across many taxa, guarding of fertile mates is a widespread tactic that enhances paternity assurance. However, guarding of mates can also occur during the nonfertile period, and the fitness benefits of this behavior are unclear. Male songbirds, for example, sometimes guard nonfertile females during foraging recesses from incubation. We hypothesized that guarding postreproductive mates may have important, but unrecognized, benefits by enhancing female foraging efficiency, thereby increasing time spent incubating eggs. We tested the hypothesis in 2 songbird species by examining female behavior during natural and experimentally induced absences of males. Male absence caused increased vigilance in foraging females that decreased their efficiency and resulted in less time spent incubating eggs. Male guarding of nonfertile females can thus provide a previously unrecognized form of indirect parental care.

  19. Effects of enoxaparin and unfractionated heparin in prophylactic and therapeutic doses on the fertility of female Wistar rats.

    Science.gov (United States)

    Figueiró-Filho, Ernesto Antonio; Aydos, Ricardo Dutra; Senefonte, Flávio Renato de Almeida; Ferreira, Cristiane Munaretto; Pereira, Erica Freire de Vasconcelos; Oliveira, Vanessa Marcon de; Menezes, Giovanna Pádoa de; Bósio, Marco Antonio Costa

    2014-07-01

    To evaluate the effects of exposure of enoxaparin and unfractionated heparin (UFH) in prophylactic and therapeutic doses on the fertility rates of pregnant healthy Wistar rats. Enoxaparin and UFH were administered in prophylactic doses 1 mg/Kg/day 72 UI/Kg/day, and in therapeutic doses at 2 mg/kg/day 400UI/Kg/day. The rats were divided into five groups. The number of live and dead foetuses was quantified. The uterine horns were dissected and the presence of early and late reabsorptions (abortions) was determined. A peffect on fertility with the use of anticoagulant drugs in pregnant healthy Wistar rats.

  20. Effects of salinity and sea salt type on egg activation, fertilization, buoyancy and early embryology of European eel, Anguilla anguilla

    DEFF Research Database (Denmark)

    Sørensen, Sune Riis; Butts, Ian; Munk, Peter

    2016-01-01

    sizes, while the remaining four salt types resulted in smaller eggs. All salt types except NaCl treatments led to high fertilization rates and had no effect on fertilization success as well as egg neutral buoyancies at 7 h post-fertilization. The study points to the importance of considering ionic...... and egg buoyancy. Egg diameter after activation, using natural seawater adjusted to different salinities, varied among female eels, but no consistent pattern emerged. Activation salinities between 30–40 practical salinity unit (psu) produced higher quality eggs and generally larger egg diameters. Chorion...

  1. Low fertility awareness in United States reproductive-aged women and medical trainees: creation and validation of the Fertility & Infertility Treatment Knowledge Score (FIT-KS).

    Science.gov (United States)

    Kudesia, Rashmi; Chernyak, Elizabeth; McAvey, Beth

    2017-10-01

    To create, validate, and use a fertility awareness survey based on current U.S. Cross-sectional study. Not applicable. Phase 1 included U.S. women ages 18-45; phase 2 included female medical students and obstetrics and gynecology trainees at two urban academic programs. Survey including demographics, the Fertility & Infertility Treatment Knowledge Score (FIT-KS) instrument, and General Nutrition Knowledge Questionnaire. Knowledge of natural fertility and infertility treatments. The FIT-KS was validated through detailed item and validity analyses. In phase 1, 127 women participated; their median age was 31 years, and 43.7% had children. Their mean FIT-KS score was 16.2 ± 3.5 (55.9% correct). In phase 2, 118 medical trainees participated; their median age was 25 years, and 12.4% had children. Their mean FIT-KS score was 18.8 ± 2.1 (64.9% correct), with year of training correlating to a higher score (r=0.40). Participant awareness regarding lifestyle factors varied, but it was particularly low regarding the effects of lubricants. The majority underestimated the spontaneous miscarriage rate and overestimated the fecundability of 40-year-old women. There was general overestimation of success rates for assisted reproductive technologies, particularly among medical trainees. The FIT-KS is validated to current U.S. data for use in both general and medical populations as a quick assessment of fertility knowledge. The knowledge gaps demonstrated in this study correlate with national trends in delayed childbearing and time to initiate treatment. For medical trainees, these results raise concerns about the quality of fertility counseling they may be able to offer patients. Greater educational outreach must be undertaken to enhance fertility awareness. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  2. Childbearing across borders: Fertility and parenthood attitudes and decisions among breast cancer survivors in USA and Portugal.

    Science.gov (United States)

    Gonçalves, Vânia; Hudson, Janella; Canavarro, Maria Cristina; Morris, Julie; Lee, M Catherine; Donovan, Kristine A; Sutton, Steven K; Vadaparampil, Susan T; Quinn, Gwendolyn P

    2018-04-16

    To compare fertility and childbearing attitudes and decisions of Portuguese and American female reproductive aged breast cancer survivors. This was a cross-sectional study of 102 young breast cancer survivors (59 from Portugal and 43 from USA). Demographic, clinical and reproductive information were collected. Fertility and parenthood attitudes and decisions were assessed through a self-report questionnaire devised specifically for the study. Fertility issues became very important after the diagnosis for most of the women (51%). Few differences existed between USA and Portuguese participants. USA participants were more likely to undergo FP (23% USA vs Portugal 5%, p = 0.01). Portuguese women were more dissatisfied with their physician's explanations about fertility (Portugal: 23% vs USA: 3%; p = 0.01). Overall, women relied on their oncologist for fertility information (70%); only Portuguese women discussed fertility with their family medicine physician (11%). Overall, women showed positive attitudes towards motherhood. Portuguese women were more likely to report their partners placed more value on the family after their illness (Portuguese agree: 55% vs USA agree: 14%; p USA and Portuguese samples were found on fertility and childbearing attitudes and decisions. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Semen collection and fertility in naturally fertile sandhill cranes

    Science.gov (United States)

    Chen, G.; Gee, G.F.; Nicolich, Jane M.; Taylor, J.A.; Urbanek, R.P.; Stahlecker, D.W.

    1997-01-01

    Aviculturists often ask if semen collection will interfere with fertility in naturally fertile pairs of cranes. We used 12 naturally fertile Florida sandhill crane (Grus canadensis pratensis) pairs for this study, 6 control and 6 experimental. All pairs had produced fertile eggs in previous years and were in out-of-doors pens scattered throughout different pen complexes, within auditory range but physically isolated. Semen was collected on Tuesday mornings and Friday afternoons from 26 February 1993 to 4 June 1993. We used standard artificial insemination methods to collect and to evaluate the semen and spermatozoa. Semen collection did not affect semen quality or quantity. Semen volume, sperm density, sperm motility, sperm morphology, sperm live, sperm number per collection, and male response to semen collection exhibited significant daily variation (P semen collection began 13 days before the first egg in the experimental group, we observed no differences in the date of first egg laid or in fertility between experimental and control groups. Also, we observed no differences in the interval between clutches or in the percentage of broken eggs between experimental and control groups. Sires consistently producing better semen samples produced fewer fertile eggs than sires producing poorer semen samples (r = 0.60).

  4. Fertilizers in cereals crops. Effect of fertilization in grain quality

    International Nuclear Information System (INIS)

    Melaj, Mariana

    1997-01-01

    In the last years the yields of the maize cultivation in the Pampeana production region have constantly increased, foreseeing higher increases of yield in the next years. Such increase is due, between other motives, to the use of hybrids of higher potential yield. There is a direct relation between the yield potential of a genotype and the nutrients demand, fact that constitutes one of the geneticists concerns. Maize hybrids reach its maximum expression when the plant is cultivated in good supplied soils with balanced quantities of nutrients that in several cases are reached with the practice of fertilization. The quantitative and qualitative vegetal response to the use of phosphate fertilizers depend of soils, of the environmental conditions, of fertilizer and the way of its application as well as of the maize hybrid that was used. To direct the practice of fertilization towards the reposition of the soil nutrients extracted by genotypes of high yield without producing excesses that increase costs and put in danger the environment, it is necessary to know the real coefficient used by the plants of the phosphorus available in the soils. The isotopic methodology allows to distinguish the phosphorus coming from two nutrient sources: soil and fertilizer, even in the juvenile phase of vegetal development and to evaluate the efficiency of fertilizers in plant nutrition. The objective of the present work was to evaluate the use of phosphorus coming from one of the phosphorus source available (soil, fertilizer), that should allow to increase and make more specific the knowledge's level of the different maize hybrids. This is obtained by determination of the grade of use of nutrient (of the soil) and of the nutrient of fertilizers, evaluating the qualitative and quantitative responses to fertilization

  5. Identification of transcription-factor genes expressed in the Arabidopsis female gametophyte

    Directory of Open Access Journals (Sweden)

    Kang Il-Ho

    2010-06-01

    Full Text Available Abstract Background In flowering plants, the female gametophyte is typically a seven-celled structure with four cell types: the egg cell, the central cell, the synergid cells, and the antipodal cells. These cells perform essential functions required for double fertilization and early seed development. Differentiation of these distinct cell types likely involves coordinated changes in gene expression regulated by transcription factors. Therefore, understanding female gametophyte cell differentiation and function will require dissection of the gene regulatory networks operating in each of the cell types. These efforts have been hampered because few transcription factor genes expressed in the female gametophyte have been identified. To identify such genes, we undertook a large-scale differential expression screen followed by promoter-fusion analysis to detect transcription-factor genes transcribed in the Arabidopsis female gametophyte. Results Using quantitative reverse-transcriptase PCR, we analyzed 1,482 Arabidopsis transcription-factor genes and identified 26 genes exhibiting reduced mRNA levels in determinate infertile 1 mutant ovaries, which lack female gametophytes, relative to ovaries containing female gametophytes. Spatial patterns of gene transcription within the mature female gametophyte were identified for 17 transcription-factor genes using promoter-fusion analysis. Of these, ten genes were predominantly expressed in a single cell type of the female gametophyte including the egg cell, central cell and the antipodal cells whereas the remaining seven genes were expressed in two or more cell types. After fertilization, 12 genes were transcriptionally active in the developing embryo and/or endosperm. Conclusions We have shown that our quantitative reverse-transcriptase PCR differential-expression screen is sufficiently sensitive to detect transcription-factor genes transcribed in the female gametophyte. Most of the genes identified in this

  6. Male fertility is reduced by chronic intermittent hypoxia mimicking sleep apnea in mice.

    Science.gov (United States)

    Torres, Marta; Laguna-Barraza, Ricardo; Dalmases, Mireia; Calle, Alexandra; Pericuesta, Eva; Montserrat, Josep M; Navajas, Daniel; Gutierrez-Adan, Alfonso; Farré, Ramon

    2014-11-01

    Obstructive sleep apnea (OSA) is characterized by intermittent hypoxia and oxidative stress. However, it is unknown whether intermittent hypoxia mimicking OSA modifies male fertility. We tested the hypothesis that male fertility is reduced by chronic intermittent hypoxia mimicking OSA in a mouse model. Case-control comparison in a murine model. University research laboratory. Eighteen F1 (C57BL/6xCBA) male mice. Mice were subjected to a pattern of periodic hypoxia (20 sec at 5% O2 followed by 40 sec of room air) 6 h/day for 60 days or normoxia. After this period, mice performed a mating trial to determine effective fertility by assessing the number of pregnant females and fetuses. After euthanasia, oxidative stress in testes was assessed by measuring the expression of glutathione peroxidase 1 (Gpx1) and superoxide dismutase-1 (Sod1) by reverse-transcription polymerase chain reaction. Sperm motility was determined by Integrated Semen Analysis System (ISAS). Intermittent hypoxia significantly increased testicular oxidative stress, showing a reduction in the expression of Gpx1 and Sod1 by 38.9% and 34.4%, respectively, as compared with normoxia (P intermittent hypoxia group (P = 0.04). The proportion of pregnant females and number of fetuses per mating was significantly lower in the intermittent hypoxia group (0.33 ± 0.10 and 2.45 ± 0.73, respectively) than in normoxic controls (0.72 ± 0.16 and 5.80 ± 1.24, respectively). These results suggest that the intermittent hypoxia associated with obstructive sleep apnea (OSA) could induce fertility reduction in male patients with this sleep breathing disorder.

  7. Comparison of unenriched versus 15N-enriched fertilizer as a tracer for N fertilizer uptake

    International Nuclear Information System (INIS)

    Meints, V.W.; Shearer, G.; Kohl, D.H.; Kurtz, L.T.

    1975-01-01

    A greenhouse experiment was conducted on three soils with differing cropping and fertilization histories to determine whether unenriched fertilizer N can be used in the same manner as 15 N-enriched fertilizer to estimate the amount of plant N derived from fertilizer. Estimates using unenriched fertilizer N were compared with estimates using two 15 N enrichment levels. Use of unenriched fertilizer N led to underestimation of the amount of fertilizer N in the plant material in four of six cases when compared to 15 N-enriched fertilizer. Standard deviations of the estimates of fertilizer-derived N in plant material were considerably greater when unenriched fertilizer was used. (U.S.)

  8. Rapid Evolution of Assortative Fertilization between Recently Allopatric Species of Drosophila.

    Science.gov (United States)

    Ahmed-Braimah, Yasir H; McAllister, Bryant F

    2012-01-01

    The virilis group of Drosophila represents a relatively unexplored but potentially useful model to investigate the genetics of speciation. Good resolution of phylogenetic relationships and the ability to obtain fertile hybrid offspring make the group especially promising for analysis of genetic changes underlying reproductive isolation separate from hybrid sterility and inviability. Phylogenetic analyses reveal a close relationship between the sister species, Drosophila americana and D. novamexicana, yet excepting their contemporary allopatric distributions, factors that contribute to reproductive isolation between this species pair remain uncharacterized. A previous report has shown reduced progeny numbers in laboratory crosses between the two species, especially when female D. novamexicana are crossed with male D. americana. We show that the hatch rate of eggs produced from heterospecific matings is reduced relative to conspecific matings. Failure of eggs to hatch, and consequent reduction in hybrid progeny number, is caused by low fertilization success of heterospecific sperm, thus representing a postmating, prezygotic incompatibility. Following insemination, storage and motility of heterospecific sperm is visibly compromised in female D. novamexicana. Our results provide evidence for a mechanism of reproductive isolation that is seldom reported for Drosophila species, and indicate the rapid evolution of postmating, prezygotic reproductive barriers in allopatry.

  9. Male mice with deleted Wolframin (Wfs1 gene have reduced fertility

    Directory of Open Access Journals (Sweden)

    Aunapuu Marina

    2009-08-01

    Full Text Available Abstract Background Wolfram Syndrome (WS is an autosomal recessive disorder characterised by non-autoimmune diabetes mellitus, optic atrophy, cranial diabetes insipidus and sensorineural deafness. Some reports have described hypogonadism in male WS patients. The aim of our study was to find out whether Wfs1 deficient (Wfs1KO male mice have reduced fertility and, if so, to examine possible causes. Methods Wfs1KO mice were generated by homologous recombination. Both Wfs1KO and wild type (wt male mice were mated with wt female mice. The number of litters and the number of pups were counted and pregnancy rates calculated. The motility and morphology of the sperm and the histology of testes were analysed. Serum testosterone and FSH concentrations were also measured. Results The pregnancy rate in wt females mated with Wfs1KO males was significantly lower than in the control group (15% vs. 32%; p Conclusion The impaired fertility of Wfs1KO male mice is most likely due to changes in sperm morphology and reduced number of spermatogenic cells. The exact mechanism through which the Wfs1 gene influences sperm morphology needs to be clarified in further studies.

  10. [Fertility transition in Peru].

    Science.gov (United States)

    Ferrando, D; Aramburu, C E

    1992-12-01

    Data from national censuses and sample surveys are the basis for this examintion of differential fertility and the fertility transition in Peru. Changes in the level and structure of fertility in the 3 major geographic regions are compared, and the role of contraceptive usage and nuptiality changes in the fertility decline are analyzed. Peru's total fertility rate was estimated at 6.85 in 1965 and has since declined to 6.56 in 1965-70, 6.00 in 1970-75, 5.30 in 1975-80, 4.65 in 1980-85, and 4.00 in 1985-90. The fertility decline varied in intensity and timing in the geographic regions. A clear fertility decline began among upper and middle income groups in the principal cities in the 1960s, spreading gradually to the urban low income sectors. Not until the late 1970s did the fertility decline spread to the rest of the population, coinciding with the years of severe economic crisis. The urban total fertility rate declined from 6 to 3.77 during 1961-86, but rural fertility increased through 1972 to 8.12, before declining slightly to 7.62 in 1981 and more markedly to 6.65 in 1986. Sociocultural and economic differences between Peru's natural regions are appreciable, and account for the contrasts in fertility trends. The greatest changes occurred in metropolitan Lima, which already had relatively low fertility in 1961. Its total fertility rate declined 44% from 5.6 in 1961 to 3.13 in 1986. Fertility declined by slightly under 40% in the rest of the coast, by almost 25% in the jungle, and by scarcely 14% in the sierra. The total fertility rates in 1961 and 1986, respectively, were 6.38 and 4.13 on the coast, 6.64 and 6.45 in the highlands, and 7.92 and 5.97 in the lowlands. The fertility decline, especially in the lower classes, was a response initially to the process of cultural modernization which in slightly over 2 decades saw a profound transformation of Peru from a rural, Andean, illiterate, and agrarian society to an urban, coastal, literate, and commercial society

  11. Effects of simulated weightlessness on meiosis. Fertilization, and early development in mice

    Science.gov (United States)

    Wolgemuth, D. J.

    1986-01-01

    The initial goal was to construct a clinostat which could support mammalian cell culture. The clinostat was selected as a means by which to simulate microgravity conditions within the laboratory, by constant re-orientation of cells with respect to the gravity vector. The effects of this simulated microgravity on in-vitro meiotic maturation of oocytes, using mouse as the model system, was investigated. The effects of clinostat rotation on fertilization in-vitro was then examined. Specific endpoints included examining the timely appearance of male and female pronuclei (indicating fertilization) and the efficiency of extrusion of the second polar body. Particular attention was paid to detecting anomalies of fertilization, including parthenogenetic activation and multiple pronuclei. Finally, for the preliminary studies on mouse embryogenesis, a key feature of the clinostat was modified, that of the position of the cells during rotation. A means was found to immobilize the cells during the clinostat reotation, permitting the cells to remain at the axis of rotation yet not interfering with cellular development.

  12. Hormonal contraceptive use lowers female intrasexual competition in pair-bonded women

    NARCIS (Netherlands)

    Cobey, Kelly D.; Klipping, Christine; Buunk, Abraham P.

    The purpose of this study was to test the influence of hormonal contraceptive use on levels of female intrasexual competition. Twenty-eight women completed a scale for intrasexual competition on three occasions: when using hormonal contraceptives and when regularly cycling at a fertile and a

  13. Sex and the Imperfect Fungi.

    Science.gov (United States)

    Dyer, Paul S; Kück, Ulrich

    2017-06-01

    Approximately 20% of species in the fungal kingdom are only known to reproduce by asexual means despite the many supposed advantages of sexual reproduction. However, in recent years, sexual cycles have been induced in a series of emblematic "asexual" species. We describe how these discoveries were made, building on observations of evidence for sexual potential or "cryptic sexuality" from population genetic analyses; the presence, distribution, and functionality of mating-type genes; genome analyses revealing the presence of genes linked to sexuality; the functionality of sex-related genes; and formation of sex-related developmental structures. We then describe specific studies that led to the discovery of mating and sex in certain Candida , Aspergillus , Penicillium , and Trichoderma species and discuss the implications of sex including the beneficial exploitation of the sexual cycle. We next consider whether there might be any truly asexual fungal species. We suggest that, although rare, imperfect fungi may genuinely be present in nature and that certain human activities, combined with the genetic flexibility that is a hallmark of the fungal kingdom, might favor the evolution of asexuality under certain conditions. Finally, we argue that fungal species should not be thought of as simply asexual or sexual, but rather as being composed of isolates on a continuum of sexual fertility.

  14. Evaluation of bull fertility in dairy and beef cattle using cow field data.

    Science.gov (United States)

    Berry, D P; Evans, R D; Mc Parland, S

    2011-01-01

    A successful outcome to a given service is a combination of both male and female fertility. Despite this, most national evaluations for fertility are generally confined to female fertility with evaluations for male fertility commonly undertaken by individual breeding organisations and generally not made public. The objective of this study was to define a pertinent male fertility trait for seasonal calving production systems, and to develop a multiple regression mixed model that may be used to evaluate male fertility at a national level. The data included in the study after editing consisted of 361,412 artificial inseminations from 206,683 cow-lactations (134,911 cows) in 2,843 commercial dairy and beef herds. Fixed effects associated with whether a successful pregnancy ensued (pregnant = 1) or not (pregnant = 0) from a given service were year by month of service, day of the week, days since calving, cow parity, level of calving difficulty experienced, whether or not the previous calving was associated with perinatal mortality, and age of the service bull at the date of insemination. Non-additive genetic effects such as heterosis and recombination loss as well as inbreeding level of the service bull, dam or mating were not associated with a successful pregnancy; there was no difference in pregnancy rate between fresh or frozen semen. Random effects included in the model were the additive genetic effect of the cow, as well as a within lactation and across lactation permanent environmental effect of the cow; pedigree group effects based on cow breed were also included via the relationship matrix. Temporal differences in the AI technician and service bull were also included as random effects. A difference in five percentage units in male fertility was evident between the average effects of different dairy and beef breeds. The correlation between raw pregnancy rates for bulls with more than 100 services (n = 431) and service bull solutions from the mixed model analysis

  15. A Z-linked sterility locus causes sexual abstinence in hybrid females and facilitates speciation in Spodoptera frugiperda.

    Science.gov (United States)

    Kost, Silvia; Heckel, David G; Yoshido, Atsuo; Marec, František; Groot, Astrid T

    2016-06-01

    In the fall armyworm, Spodoptera frugiperda (Lepidoptera, Noctuidae), two sympatric strains have been recognized that have been termed corn strain (C) and rice strain (R), referring to their most common host plants. Both strains are reproductively isolated via a distinct prezygotic barrier as well as via an intriguing postzygotic phenomenon: when R females have mated with C males, the resulting RC hybrid females exhibit dramatically reduced fertility independent of their mating partner. Here, we demonstrate that the reduced fertility is caused by the fact that these females refrain from mating, that is, females are behaviorally sterile. We identified a Z-chromosomally linked sterility locus that is most likely incompatible with yet to be identified autosomal (or cytoplasmic) factors, leading to the observed sexual abstinence. Within-chromosome mapping revealed the sterility locus to be located in an area of strongly reduced interstrain recombination. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  16. Lifespan extension without fertility reduction following dietary addition of the autophagy activator Torin1 in Drosophila melanogaster.

    Science.gov (United States)

    Mason, Janet S; Wileman, Tom; Chapman, Tracey

    2018-01-01

    Autophagy is a highly conserved mechanism for cellular repair that becomes progressively down-regulated during normal ageing. Hence, manipulations that activate autophagy could increase lifespan. Previous reports show that manipulations to the autophagy pathway can result in longevity extension in yeast, flies, worms and mammals. Under standard nutrition, autophagy is inhibited by the nutrient sensing kinase Target of Rapamycin (TOR). Therefore, manipulations of TOR that increase autophagy may offer a mechanism for extending lifespan. Ideally, such manipulations should be specific and minimise off-target effects, and it is important to discover additional methods for 'clean' lifespan manipulation. Here we report an initial study into the effect of up-regulating autophagy on lifespan and fertility in Drosophila melanogaster by dietary addition of Torin1. Activation of autophagy using this selective TOR inhibitor was associated with significantly increased lifespan in both sexes. Torin1 induced a dose-dependent increase in lifespan in once-mated females. There was no evidence of a trade-off between longevity and fecundity or fertility. Torin1-fed females exhibited significantly elevated fecundity, but also elevated egg infertility, resulting in no net change in overall fertility. This supports the idea that lifespan can be extended without trade-offs in fertility and suggest that Torin1 may be a useful tool with which to pursue anti-ageing research.

  17. Effect of X-irradiation on fecundity, fertility and longevity of the red cotton bug Dysdercus koenigii Fabr

    International Nuclear Information System (INIS)

    Srivastava, K.P.; Deshpande, D.J.

    1983-01-01

    X-irradiation of the sexes affects reproduction in D. koenigii differently. Irradiation of the male has no effect on the fecundity of the female but that of the female affects it adversely. Fertility shows fluctuations at lower doses and a linear decline at higher ones irrespective of the sex irradiated. But whereas complete sterility (infertility) sets in the female at 2000 rad, the male needs 4000 rad to induce the same in the female, which indicates a greater radiosensitivity of the former, longevity is unaffected by X-irradiation, indicating lack of correlation between sterility and longevity reported to exist in some insects. (author)

  18. Plant Reproduction: AMOR Enables Males to Respond to Female Signals.

    Science.gov (United States)

    Dresselhaus, Thomas; Coimbra, Silvia

    2016-04-25

    The pollen tube of flowering plants undertakes a long journey to transport two sperm cells for double fertilization. New work on pollen tube guidance has identified an arabinogalactan-derived ovular factor that primes tubes to respond to female gametophyte-secreted attraction signals. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Genome-wide association study for female fertility in Nordic Red cattle

    DEFF Research Database (Denmark)

    Höglund, Johanna; Buitenhuis, Albert Johannes; Guldbrandtsen, Bernt

    2015-01-01

    cattle. The sub-traits of FTI are: number of inseminations per conception (AIS) in cows (C) and heifers (H), the length in days of the interval from calving to first insemination (ICF) in cows, days from first to last insemination (IFL) in cows and heifers, and 56-day non-return rate (NRR) in cows...... and heifers. The aim of this study was first to identify QTL for FTI by conducting a genome scan for variants associated with fertility index using imputed whole genome sequence data based on 4207 Nordic Red sires, and subsequently analyzing which of the sub-traits were affected by each FTI QTL by associating......). Conclusion This study 1) shows that many markers within FTI QTL regions were significantly associated with both AISH and IFLH, and 2) identified candidate genes for FTI located on BTA6 (GPR125), BTA13 (ANKRD60), BTA15 (GRAMD1B), and BTA24 (ZNF521). It is not known how the genes/variants identified...

  20. PRELIMINARY CLINICAL OBSERVATIONS ON THE GINGIVAL-PERIODONTAL MANIFESTATIONS IN IN VITRO FERTILIZED FEMALE PATIENTS

    Directory of Open Access Journals (Sweden)

    Ana GIURA

    2012-06-01

    Full Text Available Scope of the study – determination of the types and intensity of the gingival-periodontal manifestations in in vitro fertilized pregnant women, and establishment of the role played by the hormonal treatment in the initiation and maintenance of such manifestations. Materials and method. The study was performed on patients fertilized in vitro between the years 2010-2012, in the Section of Assisted Human Reproduction of the “Panait Sârbu” Clinical Hospital of Obstretics and Ginecology – Bucuresti. All patients received the same amount and concentration of progesteronic compounds for maintaining their state of pregnancy, being examined in the first gestation weeks, immediately after confirmation of pregnancy through the β-hCG blood test. Results anddiscussion: In the last decades, the effects of estrogen and progesterone have drawn special attention from the part of the researchers. During pregnancy, the gingiva represents the maintissular target for the action of steroid hormones. Pregnancy-induced gingivitis is directly correlated with the presence of the microbial flora, known as the determining factor of the disease, being still exacerbated by the action of the sexual hormones, especially during the second and third quarter of pregnancy. Conclusions: The influence of gestational hormones upon the immune system of the organism may further contribute to the initiation and worsening of pregnancy-induced gingivitis, by reducing the immune response vs. the bacterial plaque.

  1. Mating type gene analysis in apparently asexual Cercospora species is suggestive of cryptic sex.

    Science.gov (United States)

    Groenewald, Marizeth; Groenewald, Johannes Z; Harrington, Thomas C; Abeln, Edwin C A; Crous, Pedro W

    2006-12-01

    The genus Cercospora consists of numerous important, apparently asexual plant pathogens. We designed degenerate primers from homologous sequences in related species to amplify part of the C. apii, C. apiicola, C. beticola, C. zeae-maydis and C. zeina mating type genes. Chromosome walking was used to determine the full length mating type genes of these species. Primers were developed to amplify and sequence homologous portions of the mating type genes of additional species. Phylogenetic analyses of these sequences revealed little variation among members of the C. apii complex, whereas C. zeae-maydis and C. zeina were found to be dissimilar. The presence of both mating types in approximately even proportions in C. beticola, C. zeae-maydis and C. zeina populations, in contrast to single mating types in C. apii (MAT1) and C. apiicola (MAT2), suggests that a sexual cycle may be active in some of these species.

  2. Effects of plant sex on range distributions and allocation to reproduction.

    Science.gov (United States)

    Johnson, Marc T J; Smith, Stacey D; Rausher, Mark D

    2010-05-01

    Despite an abundance of theory, few empirical studies have explored the ecological and evolutionary consequences of sex. We used a comparative phylogenetic approach to examine whether transitions between sexual and asexual reproduction are associated with changes in the size and distribution of species' geographical ranges, and their investment in reproduction. Here, we reconstructed the phylogeny of the genus Oenothera sections Oenothera and Calylophus (Onagraceae), which contain 35 sexual and 30 functionally asexual species. From each species, we collected data on the geographical distribution and variation in plant traits related to reproduction. Functionally asexual species occurred at higher latitudes, but did not differ in range size, compared with sexual species. Transitions to asexuality were associated with decreased investment in floral structures, including the length of petals, floral tubes and styles. Decreased anther size and increased seed size within asexual species also suggest altered allocation to male and female fitness. The observed range shifts are consistent with superior colonization of environments by asexual species following glaciation, and the observed changes in reproductive allocation support predictions made by models relating to the evolution of selfing. Our results suggest that the evolutionary consequences of asexual reproduction might be less restrictive than previously thought.

  3. Fertilization capacity with rainbow trout DNA-damaged sperm and embryo developmental success.

    Science.gov (United States)

    Pérez-Cerezales, S; Martínez-Páramo, S; Beirão, J; Herráez, M P

    2010-06-01

    Mammalian spermatozoa undergo a strong selection process along the female tract to guarantee fertilization by good quality cells, but risks of fertilization with DNA-damaged spermatozoa have been reported. In contrast, most external fertilizers such as fish seem to have weaker selection procedures. This fact, together with their high prolificacy and external embryo development, indicates that fish could be useful for the study of the effects of sperm DNA damage on embryo development. We cryopreserved sperm from rainbow trout using egg yolk and low-density lipoprotein as additives to promote different rates of DNA damage. DNA fragmentation and oxidization were analyzed using comet assay with and without digestion with restriction enzymes, and fertilization trials were performed. Some embryo batches were treated with 3-aminobenzamide (3AB) to inhibit DNA repair by the poly (ADP-ribose) polymerase, which is an enzyme of the base excision repair pathway. Results showed that all the spermatozoa cryopreserved with egg yolk carried more than 10% fragmented DNA, maintaining fertilization rates of 61.1+/-2.3 but a high rate of abortions, especially during gastrulation, and only 14.5+/-4.4 hatching success. Furthermore, after 3AB treatment, hatching dropped to 3.2+/-2.2, showing that at least 10% DNA fragmentation was repaired. We conclude that trout sperm maintains its ability to fertilize in spite of having DNA damage, but that embryo survival is affected. Damage is partially repaired by the oocyte during the first cleavage. Important advantages of using rainbow trout for the study of processes related to DNA damage and repair during development have been reported.

  4. The impact of freedom on fertility decline.

    Science.gov (United States)

    Campbell, Martha M; Prata, Ndola; Potts, Malcolm

    2013-01-01

    Although fertility decline often correlates with improvements in socioeconomic conditions, many demographers have found flaws in demographic transition theories that depend on changes in distal factors such as increased wealth or education. Human beings worldwide engage in sexual intercourse much more frequently than is needed to conceive the number of children they want, and for women who do not have access to the information and means they need to separate sex from childbearing, the default position is a large family. In many societies, male patriarchal drives to control female reproduction give rise to unnecessary medical rules constraining family planning (including safe abortion) or justifying child marriage. Widespread misinformation about contraception makes women afraid to adopt modern family planning. The barriers to family planning can be so deeply infused that for many women the idea of managing their fertility is not considered an option. Conversely, there is evidence that once family planning is introduced into a society, then it is normal consumer behaviour for individuals to welcome a new technology they had not wanted until it became realistically available. We contend that in societies free from child marriage, wherever women have access to a range of contraceptive methods, along with correct information and backed up by safe abortion, family size will always fall. Education and wealth can make the adoption of family planning easier, but they are not prerequisites for fertility decline. By contrast, access to family planning itself can accelerate economic development and the spread of education.

  5. The increase of the fertility of soils using the liquid organic fertilizers and fertilizers based on sugar-beet wastes.

    Science.gov (United States)

    Vyborova, Oxana

    2010-05-01

    The fertility of soil is a capacity for ensuring plants by water, nutrients, air and capacity for making optimal conditions for growth and development of plants. The result of it is a yield. The main characteristic of fertility of soil is maintenance of humus. The humus is important part of organic matter. The supporting of soil fertility is impossible by traditional methods. The amount of receiving mineral fertilizers in agriculture will not increase in future, because mineral fertilizers are very expensive. The mineral fertilizers don't influence on maintenance of total amount of humus in soil and improve the circulation of nutrients. Every hectare of fields have to receive no less than 8-10 tons of organic fertilizers, therefore we will have self-supporting balance of humus and the fertility of soils will be increasing. Consequently we are looking for new types of organic materials and we include them in modern agro technologies. One of them is an organomineral fertilizer (lignitic materials). The humic chemicals in the form of lignitic materials of natrium, potassium and ammonium are permitted for using them in agriculture at the beginning of 1984. The Department of agriculture in Russian Federation considered the problem of using humic chemicals and made a decision to use them on the fields of our country, because the lignitic materials can restore the fertility of our fields. The lignitic materials increase the amount of spore-forming bacteria, mold fungi and actinomycete. Therefore the organic decomposition occurs more strongly, the processes of humification increase the speed and the amount of humus rises in the soil. The new forming humus has a high biological activity and it improves chemical and physical soil properties. The addition of lignitic materials in soil activates different groups of microorganisms, which influence on mobilization of nutrients and transformation from potential to effective fertility. The inclusion of humic fertilizers improves

  6. Household Fertilizers Use and Soil Fertility Management Practices ...

    African Journals Online (AJOL)

    Household Fertilizers Use and Soil Fertility Management Practices in Vegetable Crops Production: The Case of Central Rift Valley of Ethiopia. ... rate, which could leads to pollution of the environment from over dose application and from runoff in to the water bodies and leaching in to the ground water with economic loss.

  7. Normal development of hamster and rabbit eggs fertilized by spermatozoa labelled with the fluorescent thiol alkylating agent, monobromobimane

    International Nuclear Information System (INIS)

    Fleming, A.D.; Cummins, J.M.; Kuehl, T.J.; Seidel, G.E. Jr.; Yanagimachi, R.

    1986-01-01

    Cauda epididymal spermatozoa of the golden hamster were labelled with the thiol-alkylating reagent, monobromobimane (MB). Female hamsters underwent uterine insemination with labelled spermatozoa at laparotomy under metofane anesthesia. All 12 females examined between 5 and 54 h postinsemination yielded a total of 83/100 (83%) eggs in the process of fertilization or embryos. Under ultraviolet (UV) exposure all exhibited a fluorescent tail which, in the 4- and 8-cell embryos, could be seen to be fraying or disintegrating. As cleavage progressed, labelled tail components came to be restricted among the blastomeres such that at the 4- and 8-cell stage the tail could be seen in only one to three blastomeres. To study complete development and pregnancy another 12 females received uterine insemination. After recovery from anesthesia (approximately equal to 4 h) these females were mated with a vasectomized male bearing a dominant genetic marker (black eyes) to allow unequivocal determination of paternity in the fetuses and young produced. Seven became pregnant with one female losing her pregnancy about Day 7 of gestation. Two females sacrificed on Day 13 produced 17 normal fetuses and one resorption. Four females delivered 16 young, all normal at birth and in subsequent growth and fertility. In addition, insemination of female rabbits with MB-labelled spermatozoa yielded normal embryos (50/52 96%) from 3 does on Day 2 and (38/64 60%) from 4 does on Days 4 or 5. Two normal litters (9 bunnies) have delivered from 3 does allowed to carry to term

  8. Laparoscopic evaluation of female infertility

    International Nuclear Information System (INIS)

    Haiderr, G.; Rani, S.; Zehra, N.; Munir, A.

    2010-01-01

    Background: Sub-fertility is inability to ensure child bearing when it is wanted. Prevalence of sub-fertility in industrialised countries has been quoted as 20%, and seems to be on the rise. Traditional way to assess the uterine cavity, tubal structure and tubal patency was hysterosalpingography but it has now been largely superseded by laparoscopy and hysteroscopy. The objective of this study was to highlight the role of laparoscopy in establishing diagnosis of female infertility. Methods: This descriptive study was conducted in Gynaecology Unit of Liaquat University of Medical Health Sciences, Hyderabad, Pakistan from August 28, 2000 to July 1, 2001. Total 200 sub-fertile patients attended the gynaecology OPD. Out of these 30 patients were selected for laparoscopy and dye test who were suspected cases of endometriosis, abnormal HSG and unexplained infertility. Those patients who had medical disorders and contraindication for laparoscopy were excluded from study. Detailed history of every patient was recorded on a proforma and physical examination was performed. Laparoscopy was scheduled in proliferative phase of menstrual cycle. Data were analysed using SPSS 11. Frequency and percentages were calculated to describe the results. Results: Out of 200 sub-fertile patients total 30 patients were selected for laparoscopy. Twenty (66%) patients were in primary infertility group while 10 (33%) patients were in secondary infertility group. Eleven (55%) patients of primary infertility belong to age group of 18-25 years while 6(60%) patients of secondary infertility belong to age group of 26- 33 years. Mean duration of sub fertility at time of presentation in primary infertility group was 1.95 years while in secondary infertility was 2.70 years. In primary infertility group main associated symptoms were dysmenorrhoeal in 8 (40%), irregular cycles 5 (25%), and dyspareunia in 4 (20%). In secondary infertility group 3 (30%) patients had dysmenorrhoeal and dyspareunia while 2

  9. Transmission rates of the bacterial endosymbiont, Neorickettsia risticii, during the asexual reproduction phase of its digenean host, Plagiorchis elegans, within naturally infected lymnaeid snails.

    Science.gov (United States)

    Greiman, Stephen E; Tkach, Vasyl V; Vaughan, Jefferson A

    2013-10-22

    Neorickettsia are obligate intracellular bacterial endosymbionts of digenean parasites present in all lifestages of digeneans. Quantitative information on the transmission of neorickettsial endosymbionts throughout the complex life cycles of digeneans is lacking. This study quantified the transmission of Neorickettsia during the asexual reproductive phase of a digenean parasite, Plagiorchis elegans, developing within naturally parasitized lymnaeid pond snails. Lymnaea stagnalis snails were collected from 3 ponds in Nelson County, North Dakota and screened for the presence of digenean cercariae. Cercariae were identified to species by PCR and sequencing of the 28S rRNA gene. Neorickettsia infections were initially detected using nested PCR and sequencing of a partial 16S rRNA gene of pooled cercariae shed from each parasitized snail. Fifty to 100 single cercariae or sporocysts were isolated from each of six parasitized snails and tested for the presence of Neorickettsia using nested PCR to estimate the efficiency at which Neorickettsia were transmitted to cercariae during asexual development of the digenean. A total of 616 L. stagnalis were collected and 240 (39%) shed digenean cercariae. Of these, 18 (8%) were Neorickettsia-positive. Six Neorickettsia infections were selected to determine the transmission efficiency of Neorickettsia from mother to daughter sporocyst and from daughter sporocyst to cercaria. The prevalence of neorickettsiae in cercariae varied from 11 to 91%. The prevalence of neorickettsiae in sporocysts from one snail was 100%. Prevalence of Neorickettsia infection in cercariae of Plagiorchis elegans was variable and never reached 100%. Reasons for this are speculative, however, the low prevalence of Neorickettsia observed in some of our samples (11 to 52%) differs from the high prevalence of other, related bacterial endosymbionts, e.g. Wolbachia in Wolbachia-dependent filariid nematodes, where the prevalence among progeny is universally 100

  10. MRI and CT of the female pelvis

    Energy Technology Data Exchange (ETDEWEB)

    Hamm, B. [Charite - Universitaetsmedizin Berlin (Germany). Inst. fuer Radiologie; Forstner, R. (eds.) [Salzburger Landeskliniken, Paracelsus Medizinische Privatuniv., Salzburg (Austria). Universitaetsinst. fuer Radiodiagnostik

    2007-07-01

    MRI and CT exquisitely depict the anatomy of the female pelvis and offer fascinating diagnostic possibilities in women with pelvic disorders. This volume provides a comprehensive account of the use of these cross-sectional imaging techniques to identify and characterize developmental anomalies and acquired diseases of the female genital tract. Both benign and malignant diseases are considered in depth, and detailed attention is also paid to normal anatomical findings and variants. Further individual chapters focus on the patient with pelvic pain and the use of MRI for pelvimetry during pregnancy and the evaluation of fertility. Throughout, emphasis is placed on the most recent diagnostic and technical advances, and the text is complemented by many detailed and informative illustrations. All of the authors are acknowledged experts in diagnostic imaging of the female pelvis, and the volume will prove an invaluable aid to everyone with an interest in this field. (orig.)

  11. MRI and CT of the female pelvis

    International Nuclear Information System (INIS)

    Hamm, B.; Forstner, R.

    2007-01-01

    MRI and CT exquisitely depict the anatomy of the female pelvis and offer fascinating diagnostic possibilities in women with pelvic disorders. This volume provides a comprehensive account of the use of these cross-sectional imaging techniques to identify and characterize developmental anomalies and acquired diseases of the female genital tract. Both benign and malignant diseases are considered in depth, and detailed attention is also paid to normal anatomical findings and variants. Further individual chapters focus on the patient with pelvic pain and the use of MRI for pelvimetry during pregnancy and the evaluation of fertility. Throughout, emphasis is placed on the most recent diagnostic and technical advances, and the text is complemented by many detailed and informative illustrations. All of the authors are acknowledged experts in diagnostic imaging of the female pelvis, and the volume will prove an invaluable aid to everyone with an interest in this field. (orig.)

  12. Globalization and Contemporary Fertility Convergence.

    Science.gov (United States)

    Hendi, Arun S

    2017-09-01

    The rise of the global network of nation-states has precipitated social transformations throughout the world. This article examines the role of political and economic globalization in driving fertility convergence across countries between 1965 and 2009. While past research has typically conceptualized fertility change as a country-level process, this study instead employs a theoretical and methodological framework that examines differences in fertility between pairs of countries over time. Convergence in fertility between pairs of countries is hypothesized to result from increased cross-country connectedness and cross-national transmission of fertility-related schemas. I investigate the impact of various cross-country ties, including ties through bilateral trade, intergovernmental organizations, and regional trade blocs, on fertility convergence. I find that globalization acts as a form of social interaction to produce fertility convergence. There is significant heterogeneity in the effects of different cross-country ties. In particular, trade with rich model countries, joint participation in the UN and UNESCO, and joining a free trade agreement all contribute to fertility convergence between countries. Whereas the prevailing focus in fertility research has been on factors producing fertility declines, this analysis highlights specific mechanisms-trade and connectedness through organizations-leading to greater similarity in fertility across countries. Globalization is a process that propels the spread of culturally laden goods and schemas impinging on fertility, which in turn produces fertility convergence.

  13. Desired Numbers of Children, Fertility Preferences and Related Factors among Couples Who Referred to Pre-Marriage Counseling in Alborz Province, Iran

    Directory of Open Access Journals (Sweden)

    Razieh Lotfi

    2017-09-01

    Full Text Available Background The Islamic Republic of Iran has experienced a dramatic decrease in fertility rates in the past three decades. One of the main issues in the field of fertility is the couple’s preferences and the desire to bear children. This study aimed to determine desired number of children, fertility preference, and related factors among people referring pre-marriage counseling to clarify their presumed behavior in case of fertility. Materials and Methods This study was a descriptive analytic cross-sectional survey, conducted during 8 months. The participants were 300 couples came to pre-marriage counseling centers of two health centers of Karaj and asked to complete a 22 items questionnaire about of demographic characteristics, participants’ interest, preference about fertility, and economic situation. Results Majority of the males were between the ages of 20-30 years (66.6% while majority of the females were below 25 years of age (57%. About 17 percent of men and 22.3 percent of women stated that they want to have 1 child and equally 52.7 percent of men and 52.7 percent of women wanted to have 2 children. The only factor that contributed to the female participant’s decision for a desirable number of children was the number of siblings that they have. In male participants with an increasing age at marriage and aspiration for higher educational level, the time interval between marriage and the birth of the first child has increased. There was a convergence in desired number of children in male and female participants. Conclusion Majority of the participants express their desire to have only one or two children in future but in considering the fact that what one desires does not always come into reality, the risk of reduced fertility is generally present in the community. Appropriate policies should be implemented in order to create a favorable environment for children.

  14. Study on the placement of phosphorus fertilizer to improve fertilizer utilization by lowland rice

    International Nuclear Information System (INIS)

    Sisworo, W.H.; Riswantoro; Mardjo, M.

    1976-01-01

    An experiment for studying the placement of phosphorus fertilizer was carried out in the glass house by using 32 P-labelled superphosphate. The specific activity of the labelled fertilizer used was 0,25 mCi/g P 2 O 5 . Three placement methods were studied: (1) Hill placement: Fertilizer was burried at a distance of 5cm from the plants at the depth of 5 cm, (2) Surface placement: Fertilizer was spread on the surface, and (3) Soil mixed application: Fertilizer was mixed with the soil at the depth of 5 cm. Superphosphate was applied at the rates of 0, 30, 60, 90, and 120 kg P 25 /ha. Results obtained from the experiment showed that the dry matter production was significantly affected by the methods of placement of phosphorus fertilizer. Soil mixed placement gave the lowest yield of dry plant material. It differed significantly from the two other methods of placement. However, there was no significant difference between hill and surface placement. The placement of phosphorus fertilizer significantly affected the total uptake of phosphorus nutrient, uptake fertilizer phosphorus, and the percentage of fertilizer utilization. Surface placement gave the highest utilization of fertilizer when supplied at rates higher than 60 kg P 2 O 5 /ha. At low rate applications, hill placement was the best, but, at rates higher than 60 kg P 2 O 5 /ha the percentage of fertilizer utilization decreased. Soil mixed application was the least efficient fertilizer utilization. (author)

  15. [Fertility and sterility in domestic animals].

    Science.gov (United States)

    de Kruif, A

    2003-01-01

    For most of the domestic animals the fertility rate is generally very good. If a uniparous female animal is served during the oestrus period by a male with good sperm quality, the pregnancy rate is 60 to 70%. Among the animals that deliver more than one offspring, in many cases the pregnancy rate even reaches more than 90%. Nevertheless, veterinarians are very frequently consulted for fertility problems in individual animals or in cattle or swine herds. The main causes of subfertility are: Insufficient sperm quality An inseminator with insufficient professional knowledge. The majority of the cows, horses and pigs are inseminated artificially (AI). The insemination is not always carried out by experts. Not the right time for insemination. It especially occurs in animals with weak oestrus symptoms. Venereal infections. In earlier days these infections would occur very often. Due to the application of AI, most of these infections have been eradicated. The malfunctioning of the female genital system, which can be caused by various factors, such as cystic ovarian follicles, endometritis and anatomic abnormalities. The research on reproduction which has been going on during the past ten years in the department of Obstetrics, Reproduction and Herd Health, has been mainly concerned with: Embryo transplantation, in vitro fertilisation and ovum pick up The evaluation of sperm quality Improved freezing methods for both sperm and embryo's The development of new insemination techniques The composition of a new diluent for fresh sperm Cystic ovarian follicles in cows Subfertility in different species of animals Next to the above mentioned study fields, the department is also involved in the research into swine fever, respiratory diseases in pigs, antibiotic resistance in pigs and cattle, mastitis and metabolic problems in cattle and salmonella infections in pigs.

  16. Effect of Pasak Bumi (Eurycoma longifolia Jack) Root In Precopulation Stage to the Fertility of Female Mouse (Mus musculus L.)

    OpenAIRE

    Marlinza, Rosa

    2012-01-01

    Pasak Bumi (Eurycoma longifolia Jack) have potency to be used to increase bodyendurance, to cure malaria drug, and to act as afrodisiak. However, the effect of pasak bumi onwomen fertility, especially at pre-copulation stage was not widely known. This research seeks toreveal the effect pasak bumi extract treated at pre-copulation phase on fertility. This experimentemploy mice (Mus Musculus L.) and was undertaken at Biology and Cemistry laboratories PMIPA, andVeterinary laboratory of Jambi Uni...

  17. Perchlorate Exposure Reduces Primordial Germ Cell Number in Female Threespine Stickleback.

    Directory of Open Access Journals (Sweden)

    Ann M Petersen

    Full Text Available Perchlorate is a common aquatic contaminant that has long been known to affect thyroid function in vertebrates, including humans. More recently perchlorate has been shown to affect primordial sexual differentiation in the aquatic model fishes zebrafish and threespine stickleback, but the mechanism has been unclear. Stickleback exposed to perchlorate from fertilization have increased androgen levels in the embryo and disrupted reproductive morphologies as adults, suggesting that perchlorate could disrupt the earliest stages of primordial sexual differentiation when primordial germ cells (PGCs begin to form the gonad. Female stickleback have three to four times the number of PGCs as males during the first weeks of development. We hypothesized that perchlorate exposure affects primordial sexual differentiation by reducing the number of germ cells in the gonad during an important window of stickleback sex determination at 14-18 days post fertilization (dpf. We tested this hypothesis by quantifying the number of PGCs at 16 dpf in control and 100 mg/L perchlorate-treated male and female stickleback. Perchlorate exposure from the time of fertilization resulted in significantly reduced PGC number only in genotypic females, suggesting that the masculinizing effects of perchlorate observed in adult stickleback may result from early changes to the number of PGCs at a time critical for sex determination. To our knowledge, this is the first evidence of a connection between an endocrine disruptor and reduction in PGC number prior to the first meiosis during sex determination. These findings suggest that a mode of action of perchlorate on adult reproductive phenotypes in vertebrates, including humans, such as altered fecundity and sex reversal or intersex gonads, may stem from early changes to germ cell development.

  18. Evaluating The Effect of Melatonin on HAS2, and PGR expression, as well as Cumulus Expansion, and Fertility Potential in Mice.

    Science.gov (United States)

    Ezzati, Maryam; Roshangar, Leila; Soleimani Rad, Jafar; Karimian, Nahid

    2018-04-01

    Infertility is a worldwide health problem which affects approximately 15% of sexually active couples. One of the factors influencing the fertility is melatonin. Also, protection of oocytes and embryos from oxidative stress inducing chemicals in the culture medium is important. The aim of the present study was to investigate if melatonin could regulate hyaluronan synthase-2 (HAS2) and Progesterone receptor (PGR) expressions in the cumulus cells of mice oocytes and provide an in vitro fertilization (IVF) approach. In this experimental study, for this purpose, 30 adult female mice and 15 adult male mice were used. The female mice were superovulated using 10 U of pregnant mare serum gonadotropin (PMSG) and 24 hours later, 10 U of human chorionic gonadotropin (hCG) were injected. Next, cumulus oocyte complexes (COCs) were collected from the oviducts of the female mice by using a matrix-flushing method. The cumulus cells were cultured with melatonin 10 μM for 6 hours and for real-time reverse transcription-polymerase chain reaction (RT-PCR) was used for evaluation of HAS2 and PGR expression levels. The fertilization rate was evaluated through IVF. All the data were analyzed using a t test. The results of this study showed that HAS2 and PGR expressions in the cumulus cells of the mice receiving melatonin increased in comparison to the control groups. Also, IVF results revealed an enhancement in fertilization rate in the experimental groups compared to the control groups. To improve the oocyte quality and provide new approaches for infertility treatment, administration of melatonin as an antioxidant, showed promising results. Thus, it is concluded that fertility outcomes can be improved by melatonin it enhances PGR. Copyright© by Royan Institute. All rights reserved.

  19. The Porphyra species of Helgoland (Bangiales, Rhodophyta)

    Science.gov (United States)

    Kornmann, P.; Sahling, P.-H.

    1991-03-01

    This revision of seven Porphyra species of Helgoland was based on a study of the structure of their fertile thalli and the behaviour of their spores. Regarding the reproductive organization the species may be arranged in two groups. P. leucosticta and P. purpureo-violacea are obligate monoecious species. Asexual thalli have never been observed in the field. The other five species are generally dioecious. Isomorphic sexual thalli and asexually propagating ones are mixed in uniform populations. Carpospores originating from sexual fusion develop into the diploid Conchocelis phase. Sporangia of asexual plants, though homologous in formation, produce spores of different kinds: aplanospores that give rise to the vegetative thallus directly (in P. umbilicalis, P. insolita n. sp. and P. ochotensis) and spores that develop into haploid Conchocelis (in P. laciniata and in P. linearis). P. laciniata — formerly considered synonymous with P. purpurea — is an independent species.

  20. What Explains the Stagnation of Female Labor Force Participation in Urban India?

    NARCIS (Netherlands)

    Klasen, S.; Pieters, J.

    2015-01-01

    Female labor force participation rates in urban India between 1987 and 2011 are surprisingly low and have stagnated since the late 1980s. Despite rising growth, fertility decline, and rising wage and education levels, married women's labor force participation hovered around 18 percent. Analysis of