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Infertility is becoming a major public health problem, with increasing frequency due to medical, environmental and societal causes. The increasingly late age of childbearing, growing exposure to endocrine disruptors and other reprotoxic products, and increasing number of medical reproductive dysfunctions (endometriosis, polycystic ovary syndrome, etc.) are among the most common causes. Fertility relies on fine-tuned control of both neuroendocrine function and reproductive behaviors, those are critically regulated by sex steroid hormones. Testosterone and estradiol exert organizational and activational effects throughout life to establish and activate the neural circuits underlying reproductive function. This regulation is mediated through estrogen receptors (ERs) and androgen receptor (AR). Estradiol acts mainly via nuclear estrogen receptors ERα and ERβ. The aim of this review is to summarize the genetic studies that have been undertaken to comprehend the specific contribution of ERα and ERβ in the neural circuits underlying the regulation of the hypothalamic-pituitary-gonadal axis and the expression of reproductive behaviors, including sexual and parental behavior. Particular emphasis will be placed on the neural role of these receptors and the underlying sex differences., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Torres, Adam, Mhaouty-Kodja and Naulé.)

Delayed parenthood is constantly increasing worldwide due to various socio-economic factors. In the last decade, a growing number of epidemiological studies have suggested a link between advanced parental age and an increased risk of diseases in the offspring. Also, poor reproductive outcome has been described in pregnancies conceived by aged parents. Similarly, animal studies showed that aging negatively affects gametes, early embryonic development, pregnancy progression, and the postnatal phenotype of resulting offspring. However, how and to what extent parental age is a risk factor for the health of future generations is still a subject of debate. Notwithstanding the limitation of an animal model, the mouse model represents a useful tool to understand not only the influence of parental age on offspring phenotype but also the biological mechanisms underlying the poor reproductive outcome and the occurrence of diseases in the descendants. The present review aims at i) providing an overview of the current knowledge from mouse model about the risks associated with conception at advanced age (e.g. neurodevelopmental and metabolic disorders), ii) highlighting the candidate biological mechanisms underlying this phenomenon, and iii) discussing on how murine-derived data can be relevant to humans., (© The Author(s) 2021. Published by Oxford University Press on behalf of Society for the Study of Reproduction. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

It was assumed for a long time that sex steroids are activating reproductive behaviors by the same mechanisms that produce their morphological and physiological effects in the periphery. However during the last few decades an increasing number of examples were identified where behavioral effects of steroids were just too fast to be mediated via changes in DNA transcription. This progressively forced behavioral neuroendocrinologists to recognize that part of the effects of steroids on behavior are mediated by membrane-initiated events. In this review we present a selection of these early data that changed the conceptual landscape and we provide a summary the different types of membrane-associated receptors (estrogens, androgens and progestagens receptors) that are playing the most important role in the control of reproductive behaviors. Then we finally describe in more detail three separate behavioral systems in which membrane-initiated events have clearly been established to contribute to behavior control., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Competing Interests: Intérêts concurrents: Aucun déclaré.

Background: While the potential adverse outcomes of prenatal exposure to unhealthy lifestyle are widely evidenced, little is known about these exposures in the periconception period. We investigated the associations between lifestyle behaviours and adverse pregnancy outcomes with a unique distinction between preconceptional- and prenatal lifestyle behaviours., Methods: A secondary analysis took place within a prospective multicentre cohort study in the Netherlands, including 3,684 pregnant women. Baseline characteristics and preconceptional and first trimester lifestyle behaviours were assessed through a self-administered questionnaire in the first trimester. Adverse pregnancy outcomes (hypertensive disorders in pregnancy (HDP), small for gestational age (SGA), gestational diabetes (GDM) and spontaneous preterm birth (sPTB)) were reported by healthcare professionals. Data were collected between 2012 and 2014 and analysed using multivariate logistic regression., Results: Women who are overweight, and especially obese, have the highest odds of developing any adverse pregnancy outcome (adjusted odds ratio (aOR) 1.61 (95 % Confidence Interval (CI) 1.31-1.99) and aOR 2.85 (95 %CI 2.20-3.68), respectively), particularly HDP and GDM. Women who prenatally continued smoking attained higher odds for SGA (aOR 1.91 (95 %CI 1.05-1.15)) compared to the reference group, but these odds decreased when women prenatally quit smoking (aOR 1.14 (95 %CI 0.59-2.21)). Women who did not use folic acid supplements tended to have a higher odds of developing adverse pregnancy outcomes (aOR 1.28 (95 %CI 0.97-1.69)), while women who prenatally started folic acid supplements did not (aOR 1.01 (95 %CI 0.82-1.25))., Conclusions: Our results indicate that smoking cessation, having a normal body mass index (BMI) and initiating folic acid supplements preconceptionally may decrease the risk of adverse pregnancy outcomes. Therefore, intervening as early as the preconception period could benefit the health of future generations.

Background: Despite research efforts in this field for more than a century, the relationship between female fertility and longevity is unclear. This study was designed to investigate this relationship in Chinese oldest-old population., Methods: The China Hainan Centenarian Cohort Study was performed in 18 cities and counties of Hainan. A total of 1,226 females, including 758 centenarian women and 468 women aged 80-99 years, were enrolled in this study. Using a standardized protocol, in-person interviews and blood analyses were conducted by a well-trained research team through home visits., Results: Centenarian women had significantly lower number of children (NOC) and higher initial childbearing age (ICA) and last childbearing age (LCA) than women aged 80-99 years (p < 0.05 for all). Multivariate logistic regression analysis showed that NOC and testosterone (T) levels were positively associated with women aged 80-99 years, when centenarian women was considered as reference (p < 0.05 for all). ICA, LCA, and estradiol (E2) levels were negatively associated with women aged 80-99 years, when centenarian women was considered as reference (p < 0.05 for all)., Conclusions: The centenarians had crucial characteristics of less and delayed childbearing, indicating a negative relationship between female fertility and longevity in Chinese oldest-old population. Serum E2 levels were positively associated and serum T levels were negatively associated with longevity. The less and late childbearing might be a significant factor of longevity, and successful aging might be promoted by reducing and delaying female childbearing., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zhu, Fu, Zhang, Tian, Zhao and Yao.)

The bioactive peptides galanin, spexin and kisspeptin have a common ancestral origin and their pathophysiological roles are increasingly the subject of investigation. Evidence suggests that these bioactive peptides play a role in the regulation of metabolism, pancreatic β-cell function, energy homeostasis, mood and behaviour in several species, including zebrafish, rodents and humans. Galanin signalling suppresses insulin secretion in animal models (but not in humans), is potently obesogenic and plays putative roles governing certain evolutionary behaviours and mood modulation. Spexin decreases insulin secretion and has potent anorectic, analgesic, anxiolytic and antidepressive-like effects in animal models. Kisspeptin modulates glucose-stimulated insulin secretion, food intake and/or energy expenditure in animal models and humans. Furthermore, kisspeptin is implicated in the control of reproductive behaviour in animals, modulation of human sexual and emotional brain processing, and has antidepressive and fear-suppressing effects. In addition, galanin-like peptide is a further member of the galaninergic family that plays emerging key roles in metabolism and behaviour. Therapeutic interventions targeting galanin, spexin and/or kisspeptin signalling pathways could therefore contribute to the treatment of conditions ranging from obesity to mood disorders. However, many gaps and controversies exist, which must be addressed before the therapeutic potential of these bioactive peptides can be established.

The Challenge Hypothesis (Wingfield et al., 1990) originally focused on adult male avian testosterone elevated in response to same-sex competition in reproductive contexts. The purpose of the present paper is to demonstrate how the Challenge Hypothesis has shaped ideas about human life histories. We conduct a citation analysis, drawing upon 400 Google Scholar citations in the human literature to identify patterns in this body of scholarship. We cover key factors, such as context and personality traits, that help explain variable testosterone responses such as winning/losing to adult competitive behavior. Findings from studies on courtship and sexual behavior indicate some variation in testosterone responses depending on factors such as motivation. A large body of research indicates that male testosterone levels are often lower in contexts of long-term committed partnerships and nurturant fathering and aligned with variation in male mating and parenting effort. As the Challenge Hypothesis is extended across the life course, DHEA and androstenedione (rather than testosterone) appear more responsive to juvenile male competitive behavior, and during reproductive senescence, baseline male testosterone levels decrease just as male life history allocations show decreased mating effort. We discuss how research on testosterone administration, particularly in older men, provides causal insight into effects of testosterone in humans, and how this "natural experiment" can be viewed in light of the Challenge Hypothesis. We synthesize central concepts and findings, such as an expanded array of costs of testosterone that inform life history tradeoffs between maintenance and reproductive effort, and we conclude with directions for future research., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Study Question: What is the likelihood of having a child within 4 years for men and women with strong short-term reproductive intentions, and how is it affected by age?, Summary Answer: For women, the likelihood of realising reproductive intentions decreased steeply from age 35: the effect of age was weak and not significant for men., What Is Known Already: Men and women are postponing childbearing until later ages. For women, this trend is associated with a higher risk that childbearing plans will not be realised due to increased levels of infertility and pregnancy complications., Study Design, Size, Duration: This study analyses two waves of the nationally representative Household, Income and Labour Dynamics in Australia (HILDA) survey. The analytical sample interviewed in 2011 included 447 men aged 18-45 and 528 women aged 18-41. These respondents expressed a strong intention to have a child in the next 3 years. We followed them up in 2015 to track whether their reproductive intention was achieved or revised., Participants/materials, Settings, Methods: Multinomial logistic regression is used to account for the three possible outcomes: (i) having a child, (ii) not having a child but still intending to have one in the future and (iii) not having a child and no longer intending to have one. We analyse how age, parity, partnership status, education, perceived ability to conceive, self-rated health, BMI and smoking status are related to realising or changing reproductive intentions., Main Results and the Role of Chance: Almost two-thirds of men and women realised their strong short-term fertility plans within 4 years. There was a steep age-related decline in realising reproductive intentions for women in their mid- and late-30s, whereas men maintained a relatively high probability of having the child they intended until age 45. Women aged 38-41 who planned to have a child were the most likely to change their plan within 4 years. The probability of realising reproductive intention was highest for married and highly educated men and women and for those with one child., Limitations, Reasons for Caution: Our study cannot separate biological, social and cultural reasons for not realising reproductive intentions. Men and women adjust their intentions in response to their actual circumstances, but also in line with their perceived ability to have a child or under the influence of broader social norms on reproductive age., Wider Implications of the Findings: Our results give a new perspective on the ability of men and women to realise their reproductive plans in the context of childbearing postponement. They confirm the inequality in the individual consequences of delayed reproduction between men and women. They inform medical practitioners and counsellors about the complex biological, social and normative barriers to reproduction among women at higher childbearing ages., Study Funding/competing Interest(s): This research was partly supported by a Research School of Social Sciences Visiting Fellowship at the Australian National University and an Australian Research Council Discovery Project (DP150104248). Éva Beaujouan's work was partly funded by the Austrian Science Fund (FWF) project 'Later Fertility in Europe' (Grant agreement no. P31171-G29). This paper uses unit record data from the HILDA Survey. The HILDA Project was initiated and is funded by the Australian Government Department of Social Services (DSS) and is managed by the Melbourne Institute of Applied Economic and Social Research (Melbourne Institute). The findings and views reported in this paper, however, are those of the authors and should not be attributed to either DSS or the Melbourne Institute. The authors have no conflicts of interest., (© The Author(s) 2019. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For permissions, please e-mail: journals.permission@oup.com.)

Successful reproduction is dependent not only on hormonal endocrine responses but also on suitable partner selection, copulatory acts, as well as associated emotional, behavioral, and cognitive processes many of which are supported by the limbic system. The reproductive hormone kisspeptin (encoded by the KISS1 / kiss1 gene) is now recognized as the key orchestrator of the reproductive axis. In addition to the hypothalamus, prominent kisspeptin neuronal populations have been identified throughout limbic and paralimbic brain regions across an assortment of species. In this review, we detail the emerging roles of kisspeptin signaling in the broader aspects of behavioral, emotional, and cognitive control. Recent studies from zebrafish through humans have provided new molecular and neural insights into the complex role of kisspeptin in interpreting olfactory and auditory cues to govern sexual partner preference, in regulating copulatory behaviors and in influencing mood and emotions. Furthermore, emerging roles for kisspeptin in facilitating memory and learning are also discussed. To this end, these findings shed new light onto the importance of kisspeptin signaling, while informing the pharmacological development of kisspeptin as a potential therapeutic strategy for individuals suffering from associated reproductive, emotional, and cognitive disorders., Competing Interests: None declared., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

The hypothalamic hormone kisspeptin (encoded by the KISS1/kiss1 gene) is the master regulator of the reproductive axis with its role in controlling gonadotrophin hormone secretion now well characterized. However, identification of kisspeptin and its cognate receptor expression within the amygdala, a key limbic brain region whose functions contribute to a broad range of physiological and behavioral processes, has heightened interest concerning kisspeptins' role in the broader aspects of reproductive physiology. In this review, we detail the important developments and key studies examining the emerging functions of this kisspeptin population. These studies provide novel advances in our understanding of the mechanisms controlling reproductive neuroendocrinology by defining the crucial role of the amygdala kisspeptin system in modulating pubertal timing, reproductive hormone secretion, and pulsatility, as well as its influence in governing-related behaviors. To this end, the role of the amygdala kisspeptin system in integrating reproductive hormone secretion with behavior sheds new light onto the potential use of kisspeptin-based therapeutics for reproductive and related psychosexual disorders., Competing Interests: None declared., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

Infertility has always been considered as a social stigma and has often been treated as socially, mentally and physically damaging experience for the childless women rather than man. Fatherhood was more a social rather than biological concept, thereby making childlessness a legitimate ground for divorce and a matter of disgrace for women. Every country has its own set of customs and traditional beliefs for the relief of childlessness. While introducing a second wife was one way to overcome the predicament of childlessness, divorce was also an available choice. There were several myths that contemplated the human concerns and their needs during ancient times. It is evident that types of the infertility and their treatment in the modern era have some historical background and different representations in the ancient civilizations. The present review discusses the historical and modern perspectives of infertility and assisted reproduction and their importance in different cultures., Competing Interests: None

This review highlights the challenges, priority areas of research and planning, strategies for regulation of services and the need to develop guidelines and laws for fertility treatments during mid-life. The success rate of all treatments is poor in advanced age women because of declining ovarian reserve and natural fertility. There is often a need of third-party involvement which has its own ethical, legal and medical issues. Welfare of children born to older women and early death of parents are important concerns. Most of the new techniques such as the pre-implantation genetic diagnosis, oocyte augmentation, use of stem cells or artificial gametes, ovarian tissue preservation and ovarian transplantation are directed to improve, preserve or replace the declining ovarian reserve. These techniques are costly and have limited availability, safety and efficacy data. Continued research and policies are required to keep pace with these techniques. The other important issues include the patients' personal autonomy and right of self-determination, welfare of offspring, public vs. private funding for research and development of new technologies vs. indiscriminate use of unproven technology. It is important that mid-life fertility is recognized as a distinct area of human reproduction requiring special considerations., Competing Interests: None

Oocyte freezing for 'social reasons' refers to women of reproductive age who are aiming to prolong, protect and secure their fertility. The term emerged to describe application of the highly promising technique, namely vitrification on oocytes retrieved through controlled ovarian stimulation (COS) from women intending to preserve their fertility for social reasons. These women opt to cryopreserve their oocytes at a point in their life when they need to postpone childbearing on the grounds of so called 'social' reasons. These reasons may include a highly driven career, absence of an adequate partner, financial instability, or personal reasons that make them feel unprepared for motherhood. This is a sensitive and multifaceted issue that entails medical, bioethical and socio-psychological components. The latest trend and the apparent increase noted on oocyte freezing for 'social reasons' has prompted our team of fertility specialists, embryologists, obstetricians, gynecologists and psychologists to proceed with a thorough, critical and all-inclusive comprehensive analysis. The wide range of findings of this analysis involve concerns of embryology and epigenetics that shape decisions made in the IVF laboratory, issues regarding obstetric and perinatal concerns on the pregnancy concluding from these oocytes and the respective delivery management and neonatal data, to the social and bioethical impact of this trend's application. This literature review refers to matters rising from the moment the 'idea' of this option is 'birthed' in a woman's thoughts, to proceeding and executing it clinically, up until the point of the pediatric follow up of the children born. We aim to shed light to the controversial issue of oocyte freezing, while objectively exhibit all aspects regarding this complex matter, as well as to respectfully approach how could the prospect of our future expectations be shaped from the impact of its application.

Background: Delayed childbearing is considered a risk factor for maternal-foetal health. As in other higher-income countries, in Spain age at maternity has steadily increased during the last two decades., Aim: To quantify the impact of the delay in the age at maternity on small for gestational age (SGA) categories of <3rd, 3rd-5th and 5th-10th percentiles., Methods: 2,672,350 singleton live births born to Spanish mothers in 2007-2015 were analysed. Adjusted relative risk was calculated to estimate the adjusted partial population attributable fractions (PAF p ) for mothers aged 35-39 and ≥40 years for each category of SGA considering the interaction between age at maternity and parity., Findings: Primipara 35-39 years old mothers have the highest PAF p in the three categories of SGA, with the maximum value for SGA <3rd percentile (2.57%, 95% CI 2.25, 2.88). PAF p for both primipara and multipara ≥40 years old mothers were less than 1%. PAF p for primipara older mothers increased significantly in 2007-2015 for the three categories of SGA, more clearly among those aged 35-39 years. The contribution of multipara mothers of both age groups did not increase significantly during the period., Conclusion: Delayed maternity is a significant adjusted risk factor for SGA, contributing to the increase of its prevalence. However, results also suggest a limited clinical impact of delayed maternity on foetal growth. Positive changes in maternal profile associated with the shift in maternal age might contribute to explain the limited impact of mothers aged 35 years and older on negative birth outcome in Spain., (Copyright © 2017 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.)

Epigenetic methodologies address mechanisms of estrogenic effects on hypothalamic and preoptic neurons, as well as mechanisms by which stress can interfere with female reproductive behaviors. Recent results are reviewed., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Within social groups of primates, males commonly compete over reproduction, but they may also rely on cooperation with other males. Theory suggests that it may be adaptive for male primates to tolerate some reproduction by other males if reproductive tolerance fosters cooperation, particularly that dominant males yield so-called reproductive concessions to subordinates to entice their cooperation. We review four recent studies that claimed to have found evidence for reproductive concessions or similar forms of reproductive tolerance. However, upon critical reevaluation of their results, no study provides conclusive support for reproductive concessions as predicted by theoretical models. Yet two studies demonstrated a form of reproductive tolerance that cannot be explained by any of the existing models, and that seems to have evolved only in multi-male, multi-female societies with diverse strategic options for males. Our article provides guidance how to study this form of reproductive tolerance in the absence of a unifying model., (© 2018 Wiley Periodicals, Inc.)

The effect of free mate choice on the relative magnitude of fitness benefits has been examined among various species. The majority of the data show significant fitness benefits of mating with partners of an individual's own choice, highlighting elevated behavioral compatibility between partners with free mate choice. Similarities between humans and other species that benefit from free mate choice led us to hypothesize that it also confers reproductive benefits in Homo sapiens. To test this hypothesis, we conducted a study among three indigenous societies-the Tsimane', Yali, and Bhotiya-who employ natural birth control. In all three samples, we compared the marriages arranged by parents with the non-arranged ones in terms of number of offspring. Here, we show that there were no significant relationships between type of marriage and the total number of alive children and number of dead children among the three sampled groups. The presented study is the first to date to examine the fitness benefits of free mate choice in humans. In discussion we present limitations of our research and discuss the possibility of love having a beneficial influence in terms of the number of offspring.

Hormones orchestrate and coordinate human female sexual development, sexuality, and reproduction in relation to three types of phenotypic changes: life history transitions such as puberty and childbirth, responses to contextual factors such as caloric intake and stress, and cyclical patterns such as the ovulatory cycle. Here, we review the endocrinology underlying women's reproductive phenotypes, including sexual orientation and gender identity, mate preferences, competition for mates, sex drive, and maternal behavior. We highlight distinctive aspects of women's sexuality such as the possession of sexual ornaments, relatively cryptic fertile windows, extended sexual behavior across the ovulatory cycle, and a period of midlife reproductive senescence-and we focus on how hormonal mechanisms were shaped by selection to produce adaptive outcomes. We conclude with suggestions for future research to elucidate how hormonal mechanisms subserve women's reproductive phenotypes., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Rituximab (RTX) has emerged as an attractive off-label treatment option for patients with myasthenia gravis (MG) refractory to other immune therapies. However, data on long-term outcome after RTX for MG are still scarce. Here we present the 10-year outcomes [median (range) 10.1 (6.7-11.2) years] with respect to efficacy, safety, costs of inhospital care, and impact on childbearing potential in all four MG patients treated by one of the authors with RTX. In all patients, RTX led to sustained clinical improvement and eventual tapering of other immune therapies. RTX was well tolerated, and complications were not observed. After the start of RTX, annual costs for hospital admissions were markedly reduced compared to costs in the year preceding RTX. Under close clinical observation, two patients had uncomplicated pregnancies giving birth to a healthy child. With regard to its efficacy, excellent tolerance, lack of complications, low frequency of repeat infusions and pending patent expiry in many countries, RTX appears to compare favourably with other immune therapies used for MG. Multicentre trials and registries are urgently needed to further address long-term safety issues and clarify the efficacy and role of RTX in managing MG., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The genetic architecture of human reproductive behavior-age at first birth (AFB) and number of children ever born (NEB)-has a strong relationship with fitness, human development, infertility and risk of neuropsychiatric disorders. However, very few genetic loci have been identified, and the underlying mechanisms of AFB and NEB are poorly understood. We report a large genome-wide association study of both sexes including 251,151 individuals for AFB and 343,072 individuals for NEB. We identified 12 independent loci that are significantly associated with AFB and/or NEB in a SNP-based genome-wide association study and 4 additional loci associated in a gene-based effort. These loci harbor genes that are likely to have a role, either directly or by affecting non-local gene expression, in human reproduction and infertility, thereby increasing understanding of these complex traits.

The evolution of monogamy and paternal care in humans is often argued to have resulted from the needs of our expensive offspring. Recent research challenges this claim, however, contending that promiscuous male competitors and the risk of cuckoldry limit the scope for the evolution of male investment. So how did monogamy first evolve? Links between mating strategies and partner availability may offer resolution. While studies of sex roles commonly assume that optimal mating rates for males are higher, fitness payoffs to monogamy and the maintenance of a single partner can be greater when partners are rare. Thus, partner availability is increasingly recognized as a key variable structuring mating behavior. To apply these recent insights to human evolution, we model three male strategies - multiple mating, mate guarding and paternal care - in response to partner availability. Under assumed ancestral human conditions, we find that male mate guarding, rather than paternal care, drives the evolution of monogamy, as it secures a partner and ensures paternity certainty in the face of more promiscuous competitors. Accordingly, we argue that while paternal investment may be common across human societies, current patterns should not be confused with the reason pairing first evolved.

The major histocompatibility complex (MHC, called HLA in humans) is an important genetic component of the immune system. Fish, birds and mammals prefer mates with different genetic MHC code compared to their own, which they determine using olfactory cues. This preference increases the chances of high MHC variety in the offspring, leading to enhanced resilience against a variety of pathogens. Humans are also able to discriminate HLA related olfactory stimuli, however, it is debated whether this mechanism is of behavioural relevance. We show on a large sample (N = 508), with high-resolution typing of HLA class I/II, that HLA dissimilarity correlates with partnership, sexuality and enhances the desire to procreate. We conclude that HLA mediates mate behaviour in humans.

In 1948, Angus Bateman published a paper on fruit flies that tested Charles Darwin's ideas of sexual selection. Based on this one fruit fly study, Bateman concluded that because males are able to produce millions of small sperm, males are likely to behave promiscuously, mating with as many females as possible. On the other hand, because females produce relatively fewer, larger, and presumably more expensive eggs, females are likely to be very discriminating in selecting only one high-quality sexual partner. He also posited that a male's reproductive success increases linearly with the number of females he is able to mate with, but that a female's reproductive success peaks after she mates with only one male. Consequently, in almost all organisms, sexual selection acts most strongly on males. These ideas became a recurring theme in attempts to explain wide-ranging differences in male and female behavior not only in nonhuman animals but also in humans. As such, Bateman's conclusions and predictions have become axiomatic and, at times, have gone unquestioned even when modern empirical data do not conform to this model. This article reviews the origins and history of these ideas and uses modern data to highlight the current and growing controversy surrounding the validity and general applicability of this paradigm.

Importance: In recent decades, a trend toward delayed childbearing is noted in developed countries. Whereas the effects of maternal age on fertility, pregnancy complications, and postnatal outcomes have been thoroughly explored, consequences of advanced paternal age are less well known. Oocyte donation cycles can be used as an optimal model to analyze the association between male ageing and reproductive outcomes with minimal confounding., Objective: The purpose of this work was to summarize the updated and relevant literature dealing with the effect of paternal age on oocyte donation outcomes., Results: According to the available evidence from oocyte donation cycles, it seems that no significant association exists between advanced paternal age and fertility. However, this evidence is based on few studies, many of which are of low quality, yielding conflicting results. In addition, the emerging evidence clearly indicates an increased risk of adverse postnatal manifestations of pregnancies conceived by older fathers, including de novo autosomal dominant disorders, impaired neurocognitive development, and increased risk of malignancy., Conclusions and Relevance: This review may be of aid to medical practitioners in counseling couples on the risks of delayed childbearing.

Oxytocin (OT) is a nonapeptide with an impressive variety of physiological functions. Among them, the 'prosocial' effects have been discussed in several recent reviews, but the direct effects on male and female sexual behavior did receive much less attention so far. As our contribution to honor the lifelong interest of Berend Olivier in the control mechanisms of sexual behavior, we decided to explore the role of OT in the present review. In the successive sections, some physiological mechanisms and the 'pair-bonding' effects of OT will be discussed, followed by sections about desire, female appetitive and copulatory behavior, including lordosis and orgasm. At the male side, the effects on erection and ejaculation are reviewed, followed by a section about 'premature ejaculation' and a possible role of OT in its treatment. In addition to OT, serotonin receives some attention as one of the main mechanisms controlling the effects of OT. In the succeeding sections, the importance of OT for 'the fruits of labor' is discussed, as it plays an important role in both maternal and paternal behavior. Finally, we pay attention to an intriguing brain area, the ventrolateral part of the ventromedial hypothalamic nucleus (VMHvl), apparently functioning in both sexual and aggressive behavior, which are at first view completely opposite behavioral systems., (Copyright © 2014 Elsevier B.V. All rights reserved.)

This article explains the model of changing the duration of the reproductive period and life span under the influence of the demographic trend towards an increase in age at first birth in modern developed countries. Acting as a factor of artificial selection, increase parental age may lead to a shift of the upper boundary of the reproductive period in the new generations, and life expectancy. The article discusses the role of a number of social factors to identify trends.

This study describes the fertility intentions and discusses the potential reproductive health needs of post-natal HIV-infected Ugandan women. HIV-infected mothers attending post-natal services in Kampala, Uganda participated in this cross-sectional study using structured interviewer administered questionnaires. Descriptive statistics and logistic regression models were used to identify predictors of desire for more children. Among 403 participants, 35% desired more children. Of these, 25% wanted another child within 2 years and 75% within 3 years or more. In multivariable analyses, believing that one's partners wanted more children (OR = 2.44; 95% CI = 1.30, 4.59) was associated with the desire for future children while having more living children was negatively associated with the desire for future children (OR = 0.08; 95% CI = 0.02, 0.39). A minority of women desired future pregnancies, and most wanted to delay pregnancy for 3 years. These women are in need of family planning (FP) methods to meet stated desires to delay or end future pregnancies. Perceived partner desire for children also impacts on women's fertility intentions, highlighting the importance of engaging men during the post-natal period.67-77)

Objectives: To explore older (35 years +) primigravid women's knowledge of the risks of delayed childbearing and to identify the characteristics of those with limited knowledge., Methods: A cross-sectional survey involving 675 primigravid women in Tehran, Iran, using a cluster random sampling method at the first prenatal visit. A validated questionnaire assessed the women's awareness of delayed-childbearing risks., Results: Women variously identified conception difficulties, gestational diabetes, hypertension, multiple birth, caesarean section, preterm delivery, stillbirth, Down's syndrome, congenital abnormality, and low birth weight, as associated with delayed childbearing. Awareness of infant risks ranged between 10 and 72%. Awareness of maternal risks were independently related to the women's educational levels (odds ratio [OR]: 1.95; 95% confidence interval [CI]: 1.12-3.38), planned pregnancy (OR: 1.87; 95% CI: 1.25-2.78) and maternal age ≥ 40 (OR: 1.24; 95% CI: 1.14-2.53). Women aware of infant risks were significantly likely to be aged ≥ 40 (OR: 1.87; 95% CI: 0.01-5.12), have post-graduate education (OR: 2; 95% CI: 1.90-4.42), and have a planned pregnancy (OR: 1.99; 95% CI: 1.03-5.12)., Conclusion: Women are largely unaware of the potential complications of delayed childbirth. Understanding the risks is important for reproductive healthcare providers and policy makers in providing appropriate information to enable women to make informed decisions on the timing of conception.

It has been long established that hormones exert enduring influences on the developing brain that direct the reproductive response in adulthood, although the cellular mechanisms by which organisational effects are maintained have not been determined satisfactorily. Recent interest in epigenetic modifications to the nervous system has highlighted the potential for hormone-induced changes to the genome that could endure for the lifespan but not be transmitted to the next generation. Preliminary evidence suggests that this is indeed possible because sex differences in the histone code and in the methylation of CpGs in the promoters of specific genes have been identified and, at times, functionally correlated with behaviour. The present review provides an overview of epigenetic processes and discusses the current state-of-the-art, and also identifies future directions., (© 2013 British Society for Neuroendocrinology.)

Delayed parenting affects fertility in women and in men, and cryopreservation of oocytes and sperm is becoming the latest trend as a solution for those who want or need to postpone procreation, in an attempt to avoid the damage medical conditions or time itself produces in gametes. Although "social freezing" is considered legitimate, its ethical and social aspects are in need of an overdue medical, public and legal debate. Assisted reproduction and cryopreservation, in combination with womb outsourcing, have opened the door to biological ectogenesis and the subsequent question of whether delayed childbearing means we should formally separate procreation from sexual activity. This article briefly summarizes what cryotechniques are capable of presently and in the near future, to separate fact from fiction. It names the implications for and discusses the practically virgin subject of the underlying responsibilities of delayed parenting techniques towards the child-to-be-not only the unborn but also the not-yet-conceived child. Considering the medical, economic, legal and social consequences of these rapidly growing developments in reproduction, several reasons point at the need to formally separate procreation from sexual activity, specifying responsibilities in the first while respecting personal choice in the second.

Background: The modern phenomenon of delayed parenthood applies not only to women but also to men, but less is known about what characterises men who are expecting their first child at an advanced age. This study investigates the sociodemographic characteristics, health behaviour, health problems, social relationships and timing of pregnancy in older first-time fathers., Methods: A cross-sectional study was conducted of 14 832 men who were expecting their first child, based on data from the Norwegian Mother and Child Cohort Study (MoBa) carried out by the Norwegian Institute of Public Health. Data were collected in 2005-2008 by means of a questionnaire in gestational week 17-18 of their partner's pregnancy, and from the Norwegian Medical Birth Register. The distribution of background variables was investigated across the age span of 25 years and above. Men of advanced age (35-39 years) and very advanced age (40 years or more) were compared with men aged 25-34 years by means of bivariate and multivariate logistic regression analyses., Results: The following factors were found to be associated with having the first child at an advanced or very advanced age: being unmarried or non-cohabitant, negative health behaviour (overweight, obesity, smoking, frequent alcohol intake), physical and mental health problems (lower back pain, cardiovascular diseases, high blood pressure, sleeping problems, previous depressive symptoms), few social contacts and dissatisfaction with partner relationship. There were mixed associations for socioeconomic status: several proxy measures of high socioeconomic status (e.g. income >65,000 €, self-employment) were associated with having the first child at an advanced or very advanced age, as were several other proxy measures of low socioeconomic status (e.g. unemployment, low level of education, immigrant background).The odds of the child being conceived after in vitro fertilisation were threefold in men aged 34-39 and fourfold from 40 years and above., Conclusions: Men who expect their first baby at an advanced or very advanced age constitute a socioeconomically heterogeneous group with more health problems and more risky health behaviour than younger men. Since older men often have their first child with a woman of advanced age, in whom similar characteristics have been reported, their combined risk of adverse perinatal outcomes needs further attention by clinicians and researchers.

Although humans are considered unusual among mammals for the intensity of care that fathers often provide offspring, little is known about the hormonal architecture regulating human paternal investment. Prolactin has important reproductive functions in both female and male mammals and other taxa, making it a candidate regulator of human paternal behavior. Notably, prolactin is higher during periods of offspring care in some species, but it is unknown if this pattern occurs in human fathers. We draw on a sample of men (n = 289; age 21-23 at baseline) from Metropolitan Cebu City, Philippines to evaluate relationships between prolactin, assayed from dried blood spots, and components of reproductive behavior and relationship status. In this sample, fathers had higher prolactin than nonfathers (P = 0.006), and fathers of infants had borderline higher prolactin than fathers of older children (P = 0.054). Among single nonfathers at baseline (2005), baseline prolactin did not predict who transitioned to fatherhood by follow-up 4.5 years later. Among nonfathers, men with greater prolactin reported more lifetime sexual partners (P = 0.050) as well as more sexual activity in the month before sampling (P = 0.060). Our results suggest that fathers in Cebu have higher prolactin than nonfathers, with hormone levels highest among fathers of young infants. Although these findings are generally consistent with evidence from other species for pronurturing effects of prolactin, evidence for positive relationships between the hormone and measures of sexual behavior at Cebu point to likely complexities in the hormone's involvement in male reproductive strategy., (Copyright © 2012 Wiley Periodicals, Inc.)

The present work represents a pilot study in the area of olfactory communication in humans. On the basis of experiments, it is demonstrated that women are able to detect, by means of smell, a number of morphological and psychological characteristics of men. The samples of sweat from 29 young men were collected, as well as anthropometry measurements (interpupillary distance, height and width of the lower jaw, and so forth) and behavioral characteristics (personality questionnaire NEO, risk-taking questionnaire, Sandra Bem masculinity and femininity indices, a self-rating on aggression Buss-Perry questionnaire). Data on hormonal status of all males were collected (testosterone and cortisol). It is demonstrated that women are able to detect both morphological (masculinity, physical health) and psychological characteristics (aggression, risk taking, neuroticism, extraversion, cooperation, etc.). The smell of men rating high on cortisol is estimated as the least attractive. On the contrary, the sweat of men with combination of high level of testosterone and low level of cortisol is considered the most attractive. Females rating of male's smell differed depending on a phase of a monthly cycle. The data obtained are discussed in the light of evolutionary basis of permanent partner choice.

Because women's faces and bodies carry different cues of reproductive value, men may attend to different perceptual cues as functions of their long-term versus short-term mating motivations. We tested this hypothesis in three experiments on 135 male and 132 female participants. When influenced by short-term rather than long-term mating motivations, men's attention was captured by (Study 1), was shifted to (Study 2), and was distracted by (Study 3) the waist/hip area rather than the face on photographs of attractive women. Similar effects were not found among the female participants in response to photographs of attractive men. These results support the evolutionary view that, similar to the attentional selectivity found in other domains of life, male perceptual attention has evolved to selectively capture and hold reproductive information about the opposite sex as a function of short-term versus long-term mating goals.

Although culture is usually thought of as the collection of knowledge and traditions that are transmitted outside of biology, evidence continues to accumulate showing how biology and culture are inseparably intertwined. Cultural conflict will occur only when the beliefs and traditions of one cultural group represent a challenge to individuals of another. Such a challenge will elicit brain processes involved in cognitive decision-making, emotional activation and physiological arousal associated with the outbreak, conduct and resolution of conflict. Key targets to understand bio-cultural differences include primitive drives-how the brain responds to likes and dislikes, how it discounts the future, and how this relates to reproductive behaviour-but also higher level functions, such as how the mind represents and values the surrounding physical and social environment. Future cultural wars, while they may bear familiar labels of religion and politics, will ultimately be fought over control of our biology and our environment.

The hormone oxytocin (OT) is released both centrally and peripherally during and after mating. Although research in humans suggests a central role in sexuality, the most reliable findings to date involve peripheral activation. This review will discuss these results and will particularly focus on understanding the most recent findings from fMRI data and the effects of exogenous peripheral OT administration. We will then consider hypotheses of the roles played by central and systemic OT release as well as their control and modulation in the female, summarizing recent findings from animal research. Finally, we will discuss the contribution of OT to the initiation of pregnancy in rodents. This article is part of a Special Issue entitled Oxytocin, Vasopressin, and Social Behavior., (Published by Elsevier Inc.)

Using a representative sample of children all born to unwed parents drawn from the Fragile Families and Child Wellbeing Study and a potential outcome approach to account for self-selection into marriage, we investigate whether marriage after childbearing has a causal effect on early child development. Comparing children with similar background characteristics and parental mate-selection patterns who differ only in terms of whether their parents marry after childbirth, we find that marriage after childbirth significantly increases a child's early cognitive performance but there is no evidence that it affects child asthma risk or behavioral outcomes.

New evidence from the Utah Population Database (UPDP) reveals that at the onset of the fertility transition, reproductive behavior was transmitted across generations - between women and their mothers, as well as between women and their husbands' family of origin. Age at marriage, age at last birth, and the number of children ever born are positively correlated in the data, most strongly among first-born daughters and among cohorts born later in the fertility transition. Intergenerational ties, including the presence of mothers and mothers-in-law, influenced the hazard of progressing to a next birth. The findings suggest that the practice of parity-dependent marital fertility control and inter-birth spacing behavior derived, in part, from the previous generation and that the potential for mothers and mothers-in-law to help in the rearing of children encouraged higher marital fertility.

Assessment of adolescent's reproductive behaviour, identification of the factors affecting this kind of behavior, represented the main goal of the study. Comprehensive examination (n=136) and interviewing (n=825) was made in female adolescents aged 14 to 19 years (randomly formed via continuous selection). Information of the state of their health, their attitude towards child - bearing and their risky habits have been evaluated. Under the present conditions, the development of the reproductive system in female adolescents is characterized by the high frequency of menstrual irregulates (24,7%), the delayed formation of the bone pelvis (25,2%) the trend for retarted development of secondary sexual characters (12,3%), the high prevalence of chronic extra genital diseases. Thus, the results of the given study proves that reproductive disorders develop under the influence of a complex of sociomedical factors and lifestyle; They predetermine reproductive abnormalities, inadequate reproductive behaviour, the low standard of knowledge of contraception.

Objectives: This project aims to answer a critically important question of public policy: Does effective child support enforcement lead to a change in the incidence of abortion across the United States?, Methods: Using state-level data collected from 1978–2003 from a variety of sources, we employ fixed effects regression analysis to examine whether financial security as measured by five types of child support enforcement effectiveness impacts abortion outcomes., Results: We find that child support enforcement effectiveness decreases the incidence of abortion as measured by the abortion rate, but not the abortion ratio., Conclusions: Income transfer policies such as child support enforcement can affect certain fertility outcomes such as abortion rates across the states.

A longitudinal, micro-level study of the effect of socioeconomic transformations on fertility mechanisms in the rural hinterland of Bologna between 1818 and 1900 (the beginning of the demographic transition) demonstrates that the premature death of a last-born child reduces the interval between two consecutive childbirths. Thus does it confirm the importance of breast-feeding in determining birth spacing. Women living in complex sharecropping households experienced a significantly higher risk of childbirth than did women in families headed by daily wage earners. In addition, the reproductive behavior of sharecroppers seemed to be substantially invariant to short-term ºuctuations in prices, whereas the laborers' group experienced a negative price effect. Both descriptive and multivariate analyses indicate a slight and gradual decrease in fertility levels during the period in question.

Although the diffusion of fertility behavior between different social strata in historical communities has received considerable attention in recent studies, the relationship between the diffusion of fertility behavior and the diffusion of people (migration) during the nineteenth century remains largely underexplored. Evidence from population registers compiled in the Historical Database of the Liège Region, covering the period of 1812 to 1900, reveals that migrant couples in Sart, Belgium, from 1850 to 1874 and from 1875 to 1899 had a reduced risk of conception. The incorporation of geographical mobility, as well as the migrant status of both husbands and wives, into this fertility research sheds light not only on the spread of ideas and behaviors but also on the possible reasons why the ideas and behaviors of immigrants might have been similar to, or different from, those of a native-born population.

Reproduction is a critically important event in every animals' life and in all vertebrates is controlled by the brain via the hypothalamic-pituitary-gonadal (HPG) axis. In many species, this axis, and hence reproductive fitness, can be profoundly influenced by the social environment. Here, we review how the reception of information in a social context causes genomic changes at each level of the HPG axis.

While estrogen-facilitated changes in gene expression constitute some of the best-analyzed biochemical phenomena in the regulation of transcription, there have been at least two aspects of this topic that have led to much experimental work about estrogen actions on brain and behavior. The first task has required parsing various behavioral and neurochemical functions according to whether they depend on estrogen receptor-α or estrogen receptor-β. The second task has been the formulation of how nuclear actions of estrogens comport with membrane-initiated actions. With respect to these issues, applications of molecular endocrine approaches to lordosis behavior came first. Currently, the last in the chain of reproductive behaviors, maternal behavior, and an entire range of neural and cognitive functions even more complex in their determinants, must be analyzed using current molecular techniques. This minireview of estrogen actions on the chain of female reproductive behaviors highlights challenging new questions about estrogen actions on cells in the brain, questions that have important practical applications far beyond traditionally studied sex behaviors.

From an ultimate perspective, the age of onset of female reproduction should be sensitive to variation in mortality rates, and variation in the productivity of non-reproductive activities. In accordance with this prediction, most of the cross-national variation in women's age at first birth can be explained by differences in female life expectancies and incomes. The within-country variation in England shows a similar pattern: women have children younger in neighbourhoods where the expectation of healthy life is shorter and incomes are lower. I consider the proximate mechanisms likely to be involved in producing locally appropriate reproductive decisions. There is evidence suggesting that developmental induction, social learning and contextual evocation may all play a role.

People's childbearing intentions change over the course of their reproductive lives. These changes have been conceptualized as occurring in response to the realization that an individual is unlikely to achieve his or her intended fertility, because of constraints such as the "biological clock" or lack of a partner. In this article, we find that changes to child-bearing plans are influenced by a much wider range of factors than this. People change their plans in response to the wishes of their partners, in response to social norms, as the result of repartnering, and as the result of learning about the costs and benefits of parenthood; there are also differences between the factors that influence men's and women's decision-making. In a departure from existing studies in this area, we use a flexible analytical framework that enables us to analyze increases in planned fertility separately from decreases. This allows us to uncover several complexities of the decision-making process that would otherwise be hidden, and leads us to conclude that the determinants of increases in planned fertility are not simply equal and opposite to the determinants of decreases.

This note analyzes the association between media exposure and reproductive behavior in 48 developing countries. A summary of part of a more extensive Demographic and Health Surveys report, it shows strong connections between media exposure and the use of modern contraception, the number of children desired, and recent fertility. Television viewing is particularly important; it is assumed to expose viewers to aspects of modern life that compete with traditional attitudes toward the family and is associated with greater use of modern contraceptive methods, with a desire for fewer children, and with lower fertility. These relationships are particularly noteworthy because the data measure only the frequency of media exposure with no information about its content.

Population decline in modern day Russia is alarmingly steep: Russia loses approximately 750 thousand people each year. To combat population decline, the Russian government instituted aggressive pro-natalist policies. The paper evaluates the capacity of new policies to change women's reproductive behavior using a socio-institutionalist theoretical framework, which analyzes the gendered interaction between the states, the labor market, and family. The paper arrives to a disappointing conclusion that while efforts to improve fertility are quite aggressive, new policies do not challenge gendered hierarchies neither in public nor in private spheres, which will further depress fertility rates of Russian women.