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Increased Infertility With Age in Men and Women
Abstract
To estimate the effects of aging on the percentage of outwardly healthy couples who are sterile (completely unable to conceive without assisted reproduction) or infertile (unable to conceive within a year of unprotected intercourse).
A prospective fecundability study was conducted in a sample of 782 couples recruited from 7 European centers for natural family planning. Women aged 18-40 years were eligible. Daily intercourse records were used to adjust for timing and frequency of intercourse when estimating the per-menstrual-cycle probability of conception. The number of menstrual cycles required to conceive a clinical pregnancy and the probability of sterility and infertility were derived from the estimated fecundability distributions for men and women of different ages.
Sterility was estimated at about 1%; this percent did not change with age. The percentage infertility was estimated at 8% for women aged 19-26 years, 13-14% for women aged 27-34 years and 18% for women aged 35-39 years. Starting in the late 30s, male age was an important factor, with the percentage failing to conceive within 12 cycles increasing from an estimated 18-28% between ages 35 and 40 years. The estimated percentage of infertile couples that would be able to conceive after an additional 12 cycles of trying varied from 43-63% depending on age.
Increased infertility in older couples is attributable primarily to declines in fertility rates rather than to absolute sterility. Many infertile couples will conceive if they try for an additional year.
... At the least, the large variation in fertility rates in the last few generations and as recently reported across diverse populations 98 combined with widely differing importance of having children reported across regions in this study suggests that the desire to have children is highly conditional on local conditions and not uniformly strong. While it is possible that as they age, these young adults will feel more inclined to reproduce, both women and men become less fertile as they age 14 . This would reduce their chances of ever reproducing. ...
... The final sample consisted of 851 participants (412 women, 439 men) from 30 countries. Participants in countries from the same geographical area were grouped into 11 regions, which varied widely in size from 9 to 200 participants: Canada/USA: Canada (29), United States of America (42); Chile (44); Eastern Europe: Czech Republic (10), Estonia (15), Hungary (41), Latvia (18), Poland (27), and Slovenia (21); Japan/Korea: Japan (6) and South Korea (3); Mexico (92); Oceania: Australia (18) and New Zealand (13); Scandinavia: Denmark (4), Finland (9), and Sweden (14); South Africa (83); Southern Europe: Greece (89), Israel (29), Italy (4), Portugal (31), and Spain (47); United Kingdom (UK) (48); Western Europe: Austria (1), Belgium (14), France (24), Germany (30), The Netherlands (44), and Switzerland (1). After initial recruitment, for those regions in which fewer than 20 women and 20 men were recruited, extra efforts were made to recruit additional individuals. ...
Every human and non-human animal must make tradeoffs in investments in terms of time, energy, and resources. The aim of this study was to extrapolate from the types of investments in survival and reproduction that non-human animals make and translate these into human motivations. 16 potential goals were presented to 851 childless, 18–23-year-old adults from 11 world regions in an online study. Each young adult was asked to weight the importance of every goal to his or her ideal life. Weights had to sum to 100, requiring tradeoffs. Results revealed striking agreement across young adults with only four goals weighted above chance: Finding a beloved romantic partner, being physically and emotionally healthy, and earning money or resources. Having lots of sexual partners was the least important goal across all world regions for both sexes. Nevertheless, men more than women valued having many sexual partners, being talented outside work, being physically strong, and having a physically attractive romantic partner. Overall, there was cultural variation in some of the less important goals. Helping young adults achieve success requires understanding their own goals, rather than focusing on popularized depictions of what young adults desire.
... Women's infertility rate is increasing and becoming a more widespread problem worldwide, impacting many women's in their reproductive age (Qiao et al., 2014). Infertility is a serious health issue that accounts large number of couples worldwide especially in older couples due to continuous decline in fertility rate (Dunson et al., 2004). About one-third of infertility cases that affect couples are largely caused by the woman, one-third by the man, one-third by a combination of the two, and 20% are left unexplained (Peterson et al., 2007). ...
In recent years, there has been a significant rise in fertility-related issues especially among women, driven by a combination of lifestyle changes, environmental factors, and underlying health conditions. The impact of this issue is widely recognizable nowadays which includes infertility, increased risk of pregnancy, declining birth rates and increasing fertility centers everywhere. The problems associated with women fertility is increasingly rising every day and this has raised the need of a natural product that can improve women fertility and reproductive health. The main aim of this study is to create a nutraceutical health beverage that contains Shatavari (Asparagus racemosus), pomegranate (Punicagranatum), flax seeds (Linum usitatissimum) and honey. The 4 main ingredients for this product were chosen based on their powerful effect on increasing women fertility and to create a potential blend with essential nutrients, vitamins and minerals. Pomegranate is rich in antioxidant, flax seeds having fatty acids and phytoestrogens, honey serves as a natural preservative and immunomodulator, and Shatavari is well known in Ayurveda for its fertility enhancing qualities. Based on the existing studies, we propose that our food product Ferti can improve women fertility, reproductive health and increasing antioxidants level in the body to maintain a good metabolism. Organoleptic studies revealed that this health drink is highly acceptable. Further studies are required to demonstrate the performance of Shatavari-infused fruit drink and their impact on the reproductive health of women at the level of ovary and oocyte. This health beverage aims to give a natural solution to improve female fertility by combining ancient indigenous herb with food technology
... However, delaying childbearing to older ages leads to a "voluntary infertility" or age-related infertility [32]. Physiological decline in fertility rates, rather than "absolute sterility," was acknowledged in a prospective study from 2004 [43]. With advancing age, oocyte number and quality decrease and rate of aneuploidy increase [44]. ...
Over the past century, profound technological, societal, and cultural transformations have significantly influenced various aspects of life, particularly the structure of families and the notion of parenthood. Fifty years ago, global concerns centered on measures to control birth rates due to fears of overpopulation. Today, policymakers are addressing efforts to counteract declining population growth that could potentially become unsustainable. This chapter explores historical events that precipitated this shift and examines whether reversing certain factors may help sustain human fertility above replacement level.
... An individual's attitude toward fertility strongly influences the formation of fertility intentions. A positive attitude toward fertility is essential for fostering a positive intention to have children and increasing fertility rates [6,36,37]. ...
In recent years, many societies have reported a delay in childbearing and a decline in fertility rates, often attributed to higher levels of education. This study assessed university students’ fertility awareness and attitudes towards childbearing and related issues. This cross-sectional study was conducted among 600 medical and non-medical university students aged 18-30 in Mazandaran Province, Iran. Data were collected using a questionnaire, and statistical analyses were performed using a t-test in SPSS version 23. The mean age of the participants was 22.4 (SD=2.3) years, with 94% being single. Most students (65.7%) expressed a desire to have children in the future. The most commonly preferred behavioral response among the students was assisted reproductive technology, followed by adoption, and lastly, accepting childlessness. The study also revealed that the most significant attitudes of male students regarding the impact of childbearing on their lives included forming a real family, fostering greater love and affection, introducing new interests into their lives, and strengthening their overall life experience. These were followed by attitudes such as gaining new perspectives on life, personal development, and leading a more fulfilling life, which were deemed relatively necessary. The least essential attitudes were related to concerns about worsening conditions in the labor market, reduced freedom, financial instability, limited opportunities and time for work and personal interests, and increased tension in marital relationships. Given the low level of fertility awareness among students and its significance in fertility management and societal fertility rates, there is a need for educational programs aimed at increasing fertility awareness among university students.
... A woman's reproductive window is narrow. After the mid-thirties, their fertility potential decreases gradually, lowering after 35 years of age (Dunson et al., 2004;Sozou & Hartshorne, 2012). Their fertility continues to decline every year until menopause because the number and quality of the primordial follicles of oocytes decrease, a process associated with lower chances of the oocytes being fertilized, and higher risks of abnormal embryos and fetal loss (Hook, 1981;Faddy et al., 1992;Nybo Andersen et al., 2000). ...
... The former includes young women with low ovarian reserve or those at risk for early ovarian failure (cancer patients, genetic conditions, severe endometriosis, unexplained background, family background) and the latter is generally age-related (Cobo et al., 2013). It is well known that advanced maternal age (>35 years) (Dunson et al., 2004;Sozou & Hartshorne, 2012) is associated with a decline in both follicular pool number and oocyte quality, as well as posing higher risks of fetal chromosomal abnormalities that result in fetal loss, representing the leading causes of age-related fertility decline (Hook, 1981;Faddy et al., 1992;Nybo Andersen et al., 2000). Currently, the proportion of women delaying childbearing until the late 3 rd to early 4 th decade of life has greatly increased, especially in Western societies (Mills et al., 2011;Schmidt et al., 2012). ...
Objective:
To compare recombinant FSH (rFSH) with highly purified-human menopausal gonadotrophin (hp-hMG) on ovarian response in women undergoing elective fertility preservation (FP).
Methods:
This retrospective study included 456 women who underwent elective FP with gonadotropin-releasing hormone (GnRH) antagonist or progestin-primed ovarian stimulation (PPOS) protocols between 01/2017-12/2021. Only the first treatment cycle of each woman was included. 341 women were stimulated with rFSH and 115 with hp-hMG, and the ovarian stimulation outcomes were compared. A multivariate linear regression assessed the impact of age, basal FSH, antral follicle count (AFC) and protocol and gonadotropin types on the outcomes.
Results:
Women in the rFSH group were significantly younger, and their AFC was significantly higher than those in the hp-hMG group (35.50±2.12 vs. 35.99±2.13years, p=0.034 and 13.76±6.08 vs. 11.84±6.06, p=0.002). There were no significant group differences in the amount (p=0.645) and duration (p=0.265) of FSH stimulation. The estradiol level was significantly lower for the rFSH group compared to the hp-hMG group (2547.18±1648.21pg/mL vs. 3468.02±2497.69pg/mL, p<0.001), while the progesterone level was significantly higher (1.33±0.75 ng/mL vs. 1.01±0.52ng/mL, p=0.001). The numbers of retrieved and MII oocytes were significantly higher for the rFSH group compared with the hp-hMG group (16.82±10.95 vs. 13.25±9.66, p=0.02, and 13.22±9.13 vs. 9.76±7.11, p=0.005), while the maturity rates were comparable (p=0.103).
Conclusions:
Patients in the rFSH group had higher numbers of both retrieved and MII oocytes when undergoing elective FP.
... With advancing age, testosterone levels in men decrease and hypogonadism can occur. Seminal fluid parameters like volume and motility decline as early as age 35 [32], and morphology may also become increasingly abnormal [33]. After the age of 40, men may suffer damage to their sperm DNA, there may be a decline in motility (40%) and viability (below 50%) [9]. ...
Background/Objectives: Male infertility is influenced by physiological factors like age, as well as lifestyle factors, including physical activity. However, the specific impact of sport activity on semen parameters, and thus on male fertility, remains unclear. Specifically, the aim of this systematic review is to evaluate how an intense regime of training may affect sperm parameters in professional and non-profession athletes. Methods: Studies reporting sperm parameters associated with high training load were included. In April 2024, three electronic databases and literature sources (PubMed, Scopus, and Web of Science) were searched. Quality appraisal was performed independently by three authors using the National Heart, Lung, and Blood Institute Quality Assessment Tools (NHLBI-QAT). Results: Four studies met the inclusion criteria, reporting a total of 156 participants. Sixteen weeks of intensive cycling training produced a significant decrease in seminal volume, sperm concentration, sperm motility, and morphology, with a return to their initial levels, except for sperm morphology and sperm concentration, after at least one week of rest. In addition, in athletes with varicocele, a 6-month stop from sports activity went a long way toward improving sperm concentration and sperm motility. However, DNA fragmentation, a greater presence of round cells, and high numbers of active macrophages were described. At least 30 days improve semen parameters in professional and non-professional athletes. Conclusions: Intensive training could worsen seminal parameters and, consequently, male fertility. However, certainty of evidence is very low, and the results should be interpreted with caution.
... A person is considered to be primarily infertile if they have never been pregnant, and secondarily infertile if they have at least one previous pregnancy. The prevention, diagnosis, and 5 treatment of infertility are all included in fertility care . Most nations still struggle to provide all women with equal access to reproductive care, especially those with low and middle incomes. ...
Failure to achieve a pregnancy after 12 months or more of regular unprotected sexual intercourse is dened as infertility. Infertility has an impact on millions of affected families and 1 communities . Estimates suggest that approximately one in every six people of reproductive age worldwide experience 2 infertility in their lifetime . The most prevalent causes of infertility in the male reproductive system include aberrant sperm shape and motility, low or absent sperm counts, and 3 issues with semen ejection. . In the female reproductive system, infertility may be caused by a range of abnormalities of the ovaries, uterus, fallopian tubes, and the endocrine 4 system, among others . Infertility can be primary or secondary. A person is considered to be primarily infertile if they have never been pregnant, and secondarily infertile if they have at least one previous pregnancy. The prevention, diagnosis, and 5 treatment of infertility are all included in fertility care . Most nations still struggle to provide all women with equal access to reproductive care, especially those with low and middle incomes. Seldom does national universal health coverage 6 prioritise fertility care. . Research studies show that women's health apps do not appropriately address the needs of patients struggling with infertility and are of low quality with 7 signicant inaccuracies in content (Zwingerman et al., 2020) . Hence fertility counsellors providing support need to design the content efciently such that the app preferred by the patient can give optimal knowledge and emotional support ,thereby supplementing the course of the treatment. Development of such patient support tools should be a priority and the connect between the fertility counsellor and the patient should be enhanced through the use of the right app.
... By self-report, male participants had not had a vasectomy or sought infertility treatment, and female participants were not using any hormonal contraceptive at the time of data collection. All couples had to be between the ages of 18 and 35 years to control for age-related fertility decline (Dunson et al., 2004) and were currently in a committed, heterosexual, sexually active relationship that had been ongoing for at least three months (range = 3-146 months; M = 26.17 months; SD = 27.08). ...
Previous research suggests that human males, like males of many mammalian and avian species, adjust their ejaculate quality in accordance with sperm competition risk. Men who spend less time with their regular female partner since the couple’s last copulation produce ejaculates with more sperm at the couple’s next copulation (Baker & Bellis, 1993). We conducted a conceptual replication of this research to investigate whether sperm competition risk predicts ejaculate adjustment in human males using additional measures of sperm competition risk (e.g., perceptions of partner infidelity, presence of potential sexual rivals) and updated laser-optic semen analysis technology. We collected data from 34 heterosexual couples (age range 18–32 years) from a university population who completed self-report surveys on their relationship dynamics and provided six ejaculate samples (three copulatory and three masturbatory) across a 45-day period. Time spent together since the couple’s last copulation was not significantly associated with ejaculate quality. However, sperm concentration for copulatory ejaculates was higher for men who perceived more potential sexual rivals. Discussion situates the current results within the literature on human sperm competition and suggests several directions for future research.
... Although the fecundability of women declines with age, many women do become pregnant in their late 30s and early 40s. European data on women who were not using contraception shows that 43 percent of women who meet the criteria for infertility and are aged 35-40 will become pregnant if they persist in trying for another 2 years without treatment (Dunson, Baird, and Colombo 2004). Therefore, it is reasonable for women to think that they might be one of the 43 percent. ...
Researchers often ask women about pregnancy intentions but seldom ask how confident women are that they will be able to become pregnant when they desire. We argue that beliefs about fertility and infertility may function as justifications for behaviors to which one is already committed. Thus, women who have delayed childbearing but who intend to become pregnant may express confidence in their ability to become pregnant, even in the face of diminished odds of conception. Using data from the National Survey of Fertility Barriers, we demonstrate that over 75 percent of women who intend a first or subsequent pregnancy express confidence that they will be able to become pregnant when they wish, even if they perceive themselves as having a fertility problem or meet medical criteria for infertility. Our results are consistent with the motivated reasoning perspective. Our findings suggest that confidence in pregnancy may be a response to social‐structural pressures to delay childbearing among women who intend to become pregnant, but not necessarily the reason for delay.
... This suggests that for couples who have not been able to conceive within a year, the prospect of natural conception remains substantial if they persist in their attempts over the next year. These findings are instrumental in comprehending how age influences the risk of female infertility and are invaluable for guiding clinical advice and therapeutic choices [49]. A retrospective analysis involving 278 adult men was conducted, and the BMI and VAI for each participant were calculated. ...
Background
Obesity stands as an essential factor contributing to infertility in women. Early identification of obese individuals leads to favorable results for female infertility. The objective of this research is to assess the association between the age-adjusted visceral adiposity index (AVAI) and female infertility.
Methods
This study was conducted using NHANES data from 2013 to 2018, in which 1,231 women aged 20–45 were selected. Infertility was defined by survey questions. AVAI was calculated using anthropometric and serum data. Covariates included demographics and lifestyle factors. Statistical analysis with R, adjusting for covariates, and assessing nonlinearity and cutoff effects.
Results
The study of 1,231 women from the NHANES database revealed that 11.94% were diagnosed with infertility. Individuals with higher AVAI scores showed increased age, WC, BMI, and reduced HDL levels, with a positive correlation between AVAI and female infertility (OR = 1.42, 95%CI: 1.26–1.60). AVAI quartiles showed a pronounced relationship with female infertility risk, with the highest quartile showing the greatest risk(OR = 9.35,95% CI: 2.96–29.55). Nonlinear and threshold effects in the relationship between AVAI and female infertility were identified, with an inflection point at -9.70. Subgroup analyses indicated significant interactions between AVAI and educational status and BMI, particularly in women with a BMI below 25 kg/m², where a high AVAI level was closely related to increased infertility risk(OR = 1.92, 95%CI: 1.44–2.58).
Conclusion
The study identifies a strong association between elevated AVAI scores and female infertility risk, especially in women with a BMI under 25 kg/m². This suggests that AVAI could be a valuable predictor in female fertility assessments.
... It appears that women with a master's degree or higher are expected to be older compared to other groups (college graduates or below), which is believed to have influenced their intention to participate in the program. As age increases, fertility declines, making it a major factor in increasing subfertility rates [29]. However, it was found that there was almost no difference in the intention to participate in the program between the group aged 34 and younger and the group aged 35 and older (p = 0.98), suggesting the need for additional research. ...
Low fertility is a critical social problem worldwide, and infertility has a prevalence of 15%. This cross-sectional study aimed to understand the factors affecting the usage and satisfaction of Korean medicine (KM) in subfertile women. An online survey was conducted from 3 November to 8 November 2021. The survey collected basic information, KM treatment experience, and satisfaction from women who experienced poor pregnancy. The t-test and chi-square test (χ2-test) were used to determine the overall characteristics of the subjects and factors affecting the utilization and satisfaction of KM treatment. Of the total of 29,465 people, 4922 read the survey email, and 601 responded. After excluding 51 respondents with questionable response patterns, 550 respondents were included in the final analysis. Of these, 43.1% (n = 237) had experience with conventional treatment, and 16.5% (n = 91) had received KM treatment. The group that received both KM treatment and CM treatment (n = 59, 24.9%) was significantly more prevalent than the group that received KM treatment alone (n = 32, 10.2%) (p = 0.00). Women who had given birth more than once or held a master’s degree were significantly more willing to participate in the ‘KM Support Project for Subfertility’ program. Our findings suggest that subfertile patients prefer integrated treatment that combines KM and CM treatments. Further studies are needed to assess the status of integrative medicine treatment, satisfaction with each KM intervention, factors for low satisfaction, and patient requirements.
... Older women and female mammals have irregular menstrual or estrous cycles, ovulation problems, lower fertility, and lower conception rates (Dunson et al., 2004). With the increase of maternal age, caesarean section, instrumental delivery, and pregnancy complications are also on the rise (Patel et al., 2017). ...
Maternal age is one of the most important factors affecting the success of maternal pregnancy. Uterine aging is the leading cause of pregnancy failure in older women. However, how uterine aging affects uterine receptivity and decidualization is unclear. In this study, naturally aged one‐year‐old female mice were used to investigate effects of maternal age on embryo implantation during early pregnancy. In our study, we found abnormal uterine receptivity in aged mice. Aged mouse uterus indicates a decrease in nuclear LAMIN A, and an increase in PRELAMIN A and PROGERIN. In aged mouse uterus, double‐stranded DNA (dsDNA) in cytoplasmic fraction is significantly increased. PROGERIN overexpression in mouse uterine epithelial cells and epithelial organoids leads to nuclear DNA leakage and impaired uterine receptivity. DNase I, DNase II, and TREX1 are obviously reduced in aged mouse uterus. Treatments with foreign DNA or STING agonist significantly downregulate uterine receptivity markers and activate cGAS‐STING pathway. Uterine estrogen (E2) concentration is significantly increased in aged mice. After ovariectomized mice are treated with a high level of E2, there are significant increase of PROGERIN and cytoplasmic DNA, and activation of cGAS‐STING pathway. CD14 is significantly increased in aged uterus. Intrauterine CD14 injection inhibits embryo implantation. In vitro CD14 treatment of cultured epithelial cells or epithelial organoids decreases uterine receptivity. Uterine abnormality in aged mouse can be partially rescued by STING inhibitor. In conclusion, uterine PROGERIN increase in aged mouse uterus results in cytoplasmic DNA accumulation and cGAS‐STING pathway activation. CD14 secretion in aged uterus impairs uterine receptivity.
... The baseline female infertility probability is about 1%, that does not change with increasing age. But the actual percentage of increases with age [17]. ...
... It appears that women with a master's degree or higher are expected to be older compared to other groups (college graduates or below), which is believed to have influenced their intention to participate in the program. As age increases, fertility declines, making it a major factor in increasing infertility rates [27]. However, it was found that there was almost no difference in the intention to participate in the program between the group aged 34 and younger and the group aged 35 and older (p=0.98), ...
Low fertility is a critical social problem worldwide, and infertility has a prevalence of 15%. This cross-sectional study aimed to understand the factors affecting the usage and satisfaction of Korean medicine (KM) in subfertile women. An online survey was conducted from November 3 to November 8, 2021. The survey collected basic information, KM treatment experience, and satisfaction from women who experienced poor pregnancy. The t-test and chi-square test (χ2-test) were used to determine the overall characteristics of the subjects and factors affecting the utilization and satisfaction of KM treatment. Of the total of 29,465 people, 4,922 read the survey email, and 601 responded. After excluding 51 insincere respondents, 550 respondents were included in the final analysis. Of these, 43.1% had experience with conventional treatment, and 15.6% had received KM treatment. Integrative subfertility treatment was significantly more common (24.9%) than KM treatment alone (10.2%) (P=0.00). Women with no childbirth experience (P=0.01) and those with a master’s degree (P=0.01) were more willing to participate in the ‘KM Support Project for Subfertility’. Our findings suggest that subfertile patients prefer integrated medical treatment over KM alone. Further studies are needed to assess the status of integrative medicine treatment, satisfaction with each KM intervention, factors for low satisfaction, and patient requirements.
... However, this service is not readily available, it is expensive, and the success rate is put at about 33% depending on many factors like patient characteristics and centre involved. [11,12] Pressure from in-laws and the society to conceive and the advancing maternal age with associated reduction in fertility rate [13] together with difficulty in assessing conventional medical therapies and assisted reproductive technology (ART) may influence a woman's decision to seek alternative health approaches such as HM. [14,15,16] HM is the prevalent form of traditional and complementary medicine use in Sub-Saharan Africa. ...
Background
Infertility is one of the major medical problems seen in the Gynaecology clinic. Herbal medicine (HM) has become one of the treatment options used to circumvent infertility problems. This study aims to explore the prevalence and predictors for HM use in the management of infertility in our region.
Methodology
The method used was a cross-sectional study of 117 women attending the infertility clinic at Central Hospital Agbor, Delta State, Nigeria. The interviewer administered a questionnaire comprised of socio-demographic characteristics, infertility-related aspects, and information on herbal medicine usage. The main outcome measure was the Prevalence of HM use for infertility treatment and the possible predictors. Analysis was done using SPSS version 22.
Results
The mean age of participants was 34.1 with a standard deviation of 6.66 years. The minimum age of participants was 23 years while the maximum age was 48 years. The prevalence of HM use was 79.9%. The factors that were significantly associated with the use of HM were marital status (p 0.033), history of primary infertility (0.026) and having used HM for the management of other ailments (0.000). Women who were married and having fertility issues were more likely to seek alternative methods like the use of HM.
Conclusion
The prevalence of use of HM among participants attending the fertility clinic was high at 79.9%. We recommend that health professionals should enquire about the use of HM as this may help in educating the patients about the health risks of using HM. There is a need to explore the potential benefits and risks of HM use.
... The medical literature has defined infertility as the failure to conceive pregnancy after a year of regular intercourse without contraceptive tools. In addition, infertility increases as the woman's age increases (Dunson et al., 2004). Regarding the infertility, the medical literature has not documented the agreement about what other factors have effect on infertility. ...
Rapidly increasing population is challenging for almost all the developing countries which triggers the issues like poverty, ill-health, illiteracy, lower living standard and environmental degradation. Female participation in labor force may increase the opportunity cost for bearing and rearing children. This increased opportunity cost for having children may put pressure on families to have less number of children and offer more women time in labor market. This induces the women to allocate more time to work and develops their preferences to have less number of children. However, taking the 400 respondents as sample size, this study was conducted in Multan division, known as area of southern Punjab, Pakistan. Keeping in view the non-negative nature of dependent variable, this study used Negative Binomial Model to find out the relationship between fertility and female labor force participation. The estimates of the model indicates that monthly income of wife, education and use of birth control devices are major factors lessening the fertility rate of females. However, this mechanism for lowering demand for children by family may be helpful in reducing fertility rate (number of children per women) and increasing economic activity and wellbeing by involving more and more women in paid work. In this way, a society can achieve the targets of birth control in an invisible way to impede the pace of undesirable population growth. Finding of proposed research may help population welfare department, Punjab and Pakistan Population council, provincial and federal government in formulating an indirect and invisible population/birth control policies to overcome the burden of over-population.
... For example, age at first birth has been increasing and remains higher for white women and women with more education (Guzzo & Schweizer, 2020;Martinez & Daniels, 2023;Matthews & Hamilton, 2016). Because age and infertility are correlated (e.g., Dunson et al., 2004;Menken, 1985), populations that delay parenthood longer may need or perceive a need for treatment for infertility. ...
... This database contains information on 51,013 cycles from 3296 women from Great Britain, Italy, France, Germany, and Belgium and includes five sets of data, as shown in Fig. 1. The database has undergone consistency checks and has been used for several studies on the menstrual cycle (72,73), fecundity (71,(74)(75)(76), and the evolution of the menstrual cycle with age (77,78). The data were obtained from women with no known cycle disorders. ...
The ovarian cycle has a well-established circa-monthly rhythm, but the mechanisms involved in its regularity are unknown. Is the rhythmicity driven by an endogenous clock-like timer or by other internal or external processes? Here, using two large epidemiological datasets (26,912 cycles from 2303 European women and 4786 cycles from 721 North American women), analyzed with time series and circular statistics, we find evidence that the rhythmic characteristics of the menstrual cycle are more likely to be explained by an endogenous clock-like driving mechanism than by any other internal or external process. We also show that the menstrual cycle is weakly but significantly influenced by the 29.5-day lunar cycle and that the phase alignment between the two cycles differs between the European and the North American populations. Given the need to find efficient treatments of subfertility in women, our results should be confirmed in larger populations, and chronobiological approaches to optimize the ovulatory cycle should be evaluated.
... Second, a woman's fertility is limited to a few days per month around ovulation, the latter not being discernible through external physical signs. Accordingly, more than 50% of all women between the ages of 19 and 39 who have regular unprotected sexual intercourse require more than two menstrual cycles to become pregnant (Dunson et al., 2004). Therefore, men can significantly increase their chances of fathering children with a particular woman through a lasting commitment. ...
Introduction
In this study, we investigated the impact of age on mate selection preferences in males and females, and explored how the formation and duration of committed relationships depend on the sex of the person making the selection.
Methods
To this end, we utilized data from the television dating shows The Bachelor and The Bachelorette. In these programs, either a single man (“bachelor”) or a woman (“bachelorette”) has the opportunity to select a potential long-term partner from a pool of candidates. Our analysis encompassed a total of n = 169 seasons from 23 different countries, beginning with the first airing in 2002.
Results
We found that the likelihood of the final couple continuing their relationship beyond the broadcast was higher in The Bachelorette than in The Bachelor, although the duration of these relationships was not significantly influenced by the type of show. On average, women were younger, both when selecting their partner and when being chosen. However, men exhibited a greater preference for larger age differences than women. Furthermore, the age of the chosen male partners significantly increased with the age of the “bachelorettes,” whereas “bachelors” consistently favored women around 25.5 years old, regardless of their own age.
Discussion
We discuss these findings within the context of parental investment theory and sexual strategies theory.
... On the other hand, female fertility decreases signi cantly in the mid to late 30s and male fertility decreases signi cantly in the late 30s. 20,21 Increasing age may aggravate the di culty of infertility treatment, and reduces the possibility of successful treatment, 22 Educational level is also found to be independently associated with the behaviors of people seeking health care for infertility. Previous literature has shown the importance of education in improving the utilization of health care. ...
Background
Infertility affects an average of 9% of reproductive-aged couples worldwide. There are still gaps in utilizing infertility health care between regions within China. This study attempts to explore different behavior patterns when people utilize infertility treatment services and related factors.
Methods
A cross-sectional survey was carried out in 17 Assisted Reproductive Technology clinics in China in 2020. Using two-step cluster analysis, different behavior patterns of health care utilization of infertile women (3507) and men (721) were identified for each sex. Taking cluster membership as the dependent variable, and age, educational level, ethnicity, etc, as the independent variables, univariate analysis and multivariate logistic regression analyses were performed for each sex group separately.
Findings
10.9% of female and 19.3% of male participants had a much longer duration (4-6.9 years) of deciding to take action to seek infertility health care and a longer time (4.5-9 years) in trying to get pregnant. Age (OR 1.128, 95% CI 1.102–1.154 for women and OR 1.082, 95% CI 1.047–1.120 for men), education level (OR 0.360, 95% CI 0.21–0.618 for women and OR 0.193, 95% CI 0.068–0.546 for men), and husband’s annual income (OR 0.545, 95% CI 0.35–0.848 for women and OR 0.585, 95% CI 0.282–1.245 for men) are independent factors associated with the different utilization of health care in China for both infertile women and men. Ethnicity (OR 2.001, 95% CI 1.476–2.713) is a prominent independent factor for infertile women, and obtaining infertility knowledge from doctors (OR 1.882, 95% CI 1.26–2.81) is an independent factor prominent for infertile men in utilizing health care. The female poor utilization group had spent more on treatments, gotten less reimbursement from the health insurance system, and had undergone further treatment regimens.
Conclusion
There are disparities in utilizing health care for infertility and some people are disadvantaged in obtaining treatment at an optimal age. Certain factors influence individuals’ utilization of infertile healthcare services.
... De igual manera se vio que al presentar una frecuencia sexual de al menos 2 o 3 veces por semana, las ta-sas de infertilidad disminuyen en todos los grupos etarios (Tabla 2). Esto ocurre porque el intervalo fértil de cada ciclo menstrual es de 5 a 6 días y las parejas con una frecuencia menor a ésta tienen una mayor probabilidad de perder esta ventana de tiempo (8) . ...
... [8][9][10][11] Trainees who do delay may encounter issues of declining fertility with increasing age. [12][13][14][15][16][17] The rate of infertility in physicians is estimated to be twice that of the general population, and one-third of infertility cases in this population have been attributed to age or diminished ovarian reserve. 9 Initiating childbearing at a later age may also increase the likelihood of adverse reproductive outcomes. ...
Background
Deciding when to pursue parenthood can be difficult for medical trainees and infertility is more common in the physician population. However, few studies have examined the views of very early career trainees. The goal of this study was to assess premedical and medical student plans for family building, knowledge of fertility, and thoughts on assisted reproductive technology, as well as institutional support for parenthood in medical school and fertility curriculum.
Methods
Web-based cross-sectional survey on Qualtrics distributed through social media and school organization-based networks. Responses were reported as frequency and percent and compared across subgroups of population with χ² tests.
Results
The study had a total of 605 premedical and medical students respondents. Most students (78%) do not have children but plan to have children in the future. Almost two-thirds (63%) of students would consider using assisted reproductive technology. More than 80% of respondents have considered or would consider oocyte cryopreservation for themselves or their partners. A majority (95%) of students are worried about balancing parenthood and a career in medicine and about their fertility declining while they complete medical training (84%). The most frequently cited barriers to family planning during medical school and residency were: limited time off during training (84%), demands of training (82%), cost of having a child (59%), and stigma of having a child during training (45%). Less than half of medical students had formal education on infertility.
Conclusions
Premedical and medical students are worried about fertility declining in training and about balancing parenthood and medical careers, but gaps in knowledge and institutional support exist.
... [2][3] However, with advancing age there is a decline in ovarian reserve and oocyte quality, with this decline accelerating significantly in women aged 35 or above. 4 Therefore, the trend of deferring motherhood for "social" reasons carries risk and has been associated with involuntary childlessness. 5 Oocyte cryopreservation involves initial stimulation of ovaries to produce oocytes, followed by a trans-vaginal egg collection procedure to generate multiple mature oocytes which are then frozen and stored for future use. ...
Introduction
This study aims to assess the motivations and treatment experiences of women undergoing social egg freezing and to understand the impact of the Covid‐19 pandemic.
Material and methods
Between January 2011 to December 2021, 191 social egg freezing patients were recruited from the Lister Fertility Clinic, London UK. Participants completed a validated questionnaire investigating patients’ perspectives of social egg freezing. A response rate of 46.6% was achieved.
Results
In all, 93.9% of women expressed concern regarding age‐related fertility decline which influenced their decision to undergo social egg freezing. The majority (89.5%) of women were not in a relationship at the time of social egg freezing and considered this a motivating factor. Also, 39.0% of participants had side effects related to treatment which affected work and social life. Participants were significantly more likely to experience side effects if they underwent multiple egg freezing cycles (χ², p < 0.01) or if they cryopreserved oocytes during the COVID‐19 pandemic (χ², p < 0.05). Of the women, 64.0% wished to have cryopreserved oocytes at a younger age, a view significantly more likely if older than 37 years at first social egg freezing cycle (χ², p < 0.001). Also, 82.3% of women reported their decision to undergo social egg freezing was not delayed due to concerns regarding COVID‐19 exposure during treatment; 44.1% considered the pandemic made them more willing to undergo social egg freezing.
Conclusions
Most participants did not regret their decision to undergo social egg freezing but the majority wished they had cryopreserved oocytes at a younger age. This highlights the importance of early education to optimize outcomes and patient choice. The egg freezing process can be stressful, women may have concerns around social egg freezing and unprecedented situations such as the COVID‐19 pandemic may alter treatment experience.
... An increasing proportion of women want to have children after 40 years of age, but more women fail to meet their fertility intentions expressed at 34-36 years of age (49). Sterility was unlikely the main cause for this as sterility was estimated at approximately 1% and it did not change with age (50). Typically, women have a biological reproductive span of approximately 37 years but fertility is not uniform through the reproductive span (51). ...
Females typically carry most of the burden of reproduction in mammals. In humans, this burden is exacerbated further, as the evolutionary advantage of a large and complex human brain came at a great cost of women’s reproductive health. Pregnancy thus became a highly demanding phase in a woman’s life cycle both physically and emotionally and therefore needs monitoring to assure an optimal outcome. Moreover, an increasing societal trend towards reproductive complications partly due to the increasing maternal age and global obesity pandemic demands closer monitoring of female reproductive health. This review first provides an overview of female reproductive biology and further explores utilization of large-scale data analysis and -omics techniques (genomics, transcriptomics, proteomics, and metabolomics) towards diagnosis, prognosis, and management of female reproductive disorders. In addition, we explore machine learning approaches for predictive models towards prevention and management. Furthermore, mobile apps and wearable devices provide a promise of continuous monitoring of health. These complementary technologies can be combined towards monitoring female (fertility-related) health and detection of any early complications to provide intervention solutions. In summary, technological advances (e.g., omics and wearables) have shown a promise towards diagnosis, prognosis, and management of female reproductive disorders. Systematic integration of these technologies is needed urgently in female reproductive healthcare to be further implemented in the national healthcare systems for societal benefit.
... The former includes young women with low ovarian reserve or those at risk for early ovarian failure (cancer patients, genetic conditions, severe endometriosis, unexplained background, family background) and the latter is generally age-related [18]. It is well known that advanced maternal age (> 35 years) [19][20] is associated with a decline in both follicular pool number and oocyte quality, as well as posing higher risks of fetal chromosomal abnormalities that result in fetal loss, representing the leading causes of age-related fertility decline [21][22][23]. Currently, the proportion of women delaying childbearing until the late 3rd to early 4th decade of life has greatly increased, especially in Western societies [24][25]. ...
Purpose: To compare recombinant FSH (rFSH) with highly purified-human menopausal gonadotrophin (hp-hMG) on ovarian response in women undergoing elective fertility preservation (FP).
Methods: This retrospective study included 456 women who underwent elective FP with gonadotropin-releasing hormone (GnRH) antagonist or progestin-primed ovarian stimulation (PPOS) protocols between 01/2017-12/2021. Three-hundred and forty-one women were stimulated with rFSH and 115 with hp-hMG, and the ovarian stimulation outcomes were compared between the two groups. A multivariate linear regression analysis assessed the impact of age, basal FSH level, antral follicle count, and protocol type on the ovarian stimulation outcomes.
Results: Women in the rFSH group were significantly younger, and their antral follicle count was significantly higher than those in the hp-hMG group (35.50±2.12 vs. 35.99±2.13 years, P = 0.034 and 13.76±6.08 vs. 11.84±6.06, P = 0.002). There were no significant group differences in the amount (P = 0.645) and duration (P = 0.265) of FSH stimulation. The peak estradiol level was significantly lower for the rFSH group compared to the hp-hMG group (2547.18±1648.21 pg/mL vs. 3468.02±2497.69 pg/mL, P < 0.001), while peak progesterone level was significantly higher (1.33±0.75 ng/mL vs. 1.01±0.52 ng/mL, P = 0.001). The numbers of retrieved and MII oocytes were significantly higher for the rFSH group compared with the hp-hMG group (16.82±10.95 vs. 13.25±9.66, P = 0.02, and 13.22±9.13 vs. 9.76±7.11, P = 0.005), while the maturity rates were comparable (P = 0.103).
Conclusion: rFSH was demonstrated to have superior oocyte yield compared to hp-hMG in ovarian hyperstimulation for women undergoing elective FP.
... 5 In a study conducted in European population also, it was observed that women aged 19 years to 26 years had significantly higher probabilities of pregnancy than women aged 27 years to 29 years. 9 It is widely accepted that the infertility problems grow more with increasing age, with peak rate of conception occurring at the age of 24 years for both men and women and declines considerably after the age of 35 years. 10 Up to 30% of couple who are unable to conceive are determined to have unexplained infertility. ...
Background: Infertility is defined as not being able to conceive after one year or longer period of regular unprotected sex. Infertility is an experience that not only strikes at the very core of a couple’s life but also the whole family and society. Objectives: This study was aimed to establish the various determinants inclusive of diverse male and female factors that are responsible in causing primary or secondary infertility. Methods: A descriptive cross-sectional study was conducted after ethical approval among 448 couples attending infertility clinic in a Tertiary Care Maternity Hospital from 16th July 2018 to 15th July 2019. Convenient sampling was done. All infertile couples who visited hospital’s infertility clinic during the study period were included in the study. Clinicodemographic and diagnostics details were recorded and analysed using SPSS 20. Results: Majority of the couples had primary infertility (326, 74.4%). Mean age of the females was 28.08 ± 5.23 years and males was 31 ± 5.7 years. Most of the infertile couples had unexplained infertility followed by female and male factor. Most common female contributing factors was tubal factor (45, 35.16%), followed by ovarian factor (41, 32.2%). Only 104 (23.6%) of the semen analysis had abnormal result among which most common findings was asthenozoospermia. Conclusion: Primary infertility is more common than secondary infertility. Tubal factor was the most common female contributory factor while asthenozoospermia was predominantly seen among male partners with abnormal semen analysis.
This committee opinion provides practitioners with suggestions for optimizing the likelihood of achieving pregnancy in couples or individuals attempting conception who have no evidence of infertility. This document replaces the document of the same name previously published in 2013 (Fertil Steril 2013;100:631–7).
Background
Reduced greenness and increased nighttime light (NTL) have been associated with adverse health outcomes; however, the impacts of greenness and NTL on human fecundability remain uncertain.
Methods
Data was collected from 14,239,365 couples across 31 provinces in China. Greenness exposure was estimated using the Normalized Difference Vegetation Index (NDVI) within 1000-m buffer zones, while NTL data was derived from the Visible and Infrared Imaging Suite Day Night Band aboard satellites, both based on individual residential addresses. Fecundability among the couple participants was measured as time to pregnancy in cycles. The associations between fecundability and annual greenness or NTL exposure were assessed using variable-adjusted accelerated failure time models. Further, subgroup analyses were performed based on couples’ age, body mass index, educational levels, registration regions, and other environmental factors.
Results
Each interquartile range (IQR) increase in annual NDVI levels was significantly associated with shorter TTP (time ratio: 0.9881; 95% confidence interval [95% CI]: 0.9862, 0.9901), while per IQR increase in annual NTL level was significantly associated with longer TTP (time ratio: 1.0340; 95%CI: 1.0326, 1.0354). The associations were more pronounced among participants who were older, overweight, had lower educational levels, resided in urban regions, or lived in areas with poorer environmental conditions.
Conclusion
This cohort study has revealed that decreased greenness and increased NTL exposure were associated with reduced couple fecundability, highlighting the importance of developing greener and healthier cities in prompting global reproductive health.
Background
Male infertility is a significant global public health issue, with modifiable lifestyle factors such as smoking, obesity, and psychological stress contributing to impaired semen quality and hormonal dysregulation. This study investigates the relationships between modifiable lifestyle factors, reproductive hormones, and semen quality in Ghanaian males attending an IVF clinic.
Methods
A cross-sectional study was conducted with 212 male participants recruited from a fertility clinic in Ghana. Lifestyle factors were assessed using standardized questionnaires, and semen samples were analyzed following WHO guidelines. Hormonal profiles (LH, FSH, testosterone, estradiol) were measured using the enzyme-linked fluorescent assay (ELFA). Statistical analyses included Pearson's product-moment correlation and Bonferroni correction.
Results
Smoking and psychological stress were significantly associated with reduced sperm motility, viability, and concentration ( p < 0.05). Elevated BMI correlated negatively with sperm concentration and testosterone levels ( p < 0.05). Alcoholic bitters was linked to decreased semen quality, while caffeine consumption showed a positive association with progressive sperm motility.
Conclusion
Modifiable lifestyle factors, such as smoking, psychological stress, and increased body mass index (BMI), play a crucial role in male reproductive health by adversely affecting semen parameters and hormonal balance. These findings emphasize the need for public health interventions targeting modifiable behaviors to improve fertility outcomes.
Marital satisfaction is a major need for individuals in marital relationships. Inability to satisfy this needs often arise as a result of irreconcilable differences or inability to communicate marital preferences with partners. Conflict has been said to be either constructive or destructive and it is often described as inevitable in human relations, marriage inclusive. Every marriage inevitably experiences conflict, no matter how compatible the partners' may be. Even the healthiest of relationships occasionally descend to unpleasant conflicts. This study therefore aimed to investigate communication apprehension, age, and educational qualification as predictors of marital conflict among couples in Ado, Ekiti. Sample for this study consisted of 250 married participants, both male and female. The research employed a survey method in that the researcher administered the questionnaires to married participants in Ado-Ekiti, and all questionnaires were appropriately filled and retrieved. Four hypotheses were tested. The result shows that communication apprehension has a significant influence on marital conflict (t (248) = 1.02, p <.05). The result also revealed that age does not have a significant influence on marital conflict (F (3, 246) =.295P>.05), and educational qualification does not significantly influence marital conflict (F (5,239) = .389P>.05). Results further revealed that sex does not have a significant influence on marital conflict (t (24) =-1.540 P>.05). It was recommended that effective communication exist among couple in order to ameliorate deepened marital conflict.
People with ovaries experience reproductive aging as their reproductive function and system declines. This has significant implications for both fertility and long-term health, with people experiencing an increased risk of cardiometabolic disorders after menopause. Reproductive aging can be assessed through markers of ovarian reserve, response to fertility treatment or molecular biomarkers, including DNA methylation. Changes in DNA methylation with age associate with poorer reproductive outcomes, and epigenome-wide studies can provide insight into genes and pathways involved. DNA methylation-based epigenetic clocks can quantify biological age in reproductive tissues and systemically. This review provides an overview of hallmarks and theories of aging in the context of the reproductive system, and then focuses on studies of DNA methylation in reproductive tissues.
Objective
To determine if the introduction of value-based healthcare (VBHC) in fertility care can help to create realistic expectations in patients resulting in increased patient value, by demonstrating the relevance of defining outcome measures that truly matter to subfertile patients.
Design
Retrospective cohort study.
Setting
Tertiary fertility centre.
Results
Time to pregnancy (TTP) and ongoing pregnancy rate (OPR), as a proxy for the live birth rate, for the full cycle of fertility care, regardless of which and how many treatment cycles performed, were identified as the most relevant medical outcome measures. Outcome measures were incorporated into a digital dashboard by using anonymised and validated patient data from the electronic patient file. We were able to present the TTP and OPR for the population as a whole as well as stratified for age, diagnosis, gravidity and type of gamete source used thereby resulting in a virtual ‘patient like me’ resembling the individual patient in the consultation room.
Conclusion
We have shown that, by applying VBHC principles, relevant outcome measures can be generated and stratified for different patient characteristics, in order to develop a virtual ‘patient like me’. This virtual ‘patient like me’ can be used in the consulting room in the form of a digital dashboard, attributing to create realistic patient expectations. This facilitates healthcare providers and patients in shared decision-making.
Attractiveness is a proposed universal cue to overall biological quality. Nonetheless, local raters and raters of the same ethnicity may be more accurate in assessing the cues for attractiveness than distant and unfamiliar raters. Shared ethnicity and shared environment may both affect rating accuracy: our aim was to compare their relative influence. Therefore, we photographed young Vietnamese participants (N = 93, 33 women) from Hanoi, Vietnam. The photographs were rated by Czechs, Asian Vietnamese, and Czech Vietnamese (raters of Vietnamese origin who lived in Czechia for all or most of their life). Using geometric morphometrics, we measured facial shape cues to biological quality: averageness, asymmetry, and sexual dimorphism. We expected that Vietnamese raters residing in Czechia and Vietnam would agree on perceived attractiveness and use shape-related facial cues to biological quality better than Czech European raters, who are less familiar with East Asians. Surprisingly, mixed-effect models and post hoc comparisons identified no major cross-group differences in attributed attractiveness and path analyses revealed that the three groups based their rating on shape-related characteristics in a similar way. However, despite the considerable cross-cultural agreement regarding perceived attractiveness, Czech European raters associated attractiveness with facial shape averageness significantly more than Vietnamese raters.
Like other Nordic countries Norway has been investing heavily in family policy to enable combining work and family life. Nevertheless, between 2009 and 2022 the Total Fertility Rate (TFR) in Norway dropped from 2 children to 1.4 children per woman. What is happening, and why? Can Norwegian parents still reconcile work and family commitments? What role do demographic trends play for the future of the Norwegian society? Should we worry? These are some of the questions that this study addresses. It illustrates various aspects of fertility trends, as well as changes in the Norwegian labour market as well as in Norway’s comprehensive system of public family support. The study also looks at social attitudes and how these might be affecting family formation and fertility trends. The final chapter projects demographic, economic, fiscal and social outcomes under different fertility trend scenarios.
Introduction:
In Senegal, marital infertility is a real problem for society. We undertook the study of this subject to make an analysis of the spermatic parameters of the infertile Senegalese man and to better understand the impact of testicular morphological anomalies on male fertility.
Patients and methods:
We conducted a cross-sectional, descriptive, retrospective study of 100 infertile patients followed at the Histology-Embryology-Cytogenetics laboratory of UCAD in Dakar, during the year 2020. Sperm parameters, presence of varicocele, and testicular volume were evaluated in our patients.
Results/discussion:
The mean age of the patients was 35.17±8.7 years. A history of sexually transmitted infections was found in 57% of patients. The mean duration of infertility was 5.67±3.2 years. The mean sperm count was 14,871,230/ml±4,950,000. Necrospermia was the most frequent abnormality found (60%), followed by asthenospermia (51%). The high rate of necrospermia could be explained by the high frequency of sexually transmitted infections. Other abnormalities were oligospermia (48%, including 09% cryptospermia), azoospermia (19%), teratospermia (19%), and hypospermia (13%). The predominance of azoospermia and oligospermia should prompt a search for a genetic predisposition in these subjects. The mean testicular volume was 10.3±4.9 cc on the right and 9.5±4.8 cc on the left. A single or bilateral varicocele was found in 43% of subjects. Patients with azoospermia and teratospermia were associated with testicular hypotrophy with a significant value (p=0.04).
Conclusion:
Overall, the senegalese man consulting for infertility is a young adult, married for an average of 5 years. Necrospermia is the most frequently found anomaly. The severity of both qualitative and quantitative abnormalities should lead to a systematic search for a genetic origin. The etiological research of infertile patients must be done within a multidisciplinary framework to propose better management of these patients.
Delay in age at first marriage has been hypothesized as a significant determinant of worldwide fertility decline in high-income countries. Testing this hypothesis is challenging because age at first marriage is confounded with unobservable variables such as career aspiration. To overcome the endogeneity issue in the age at first marriage variable, this paper exploits exact date of birth that creates an exogenous variation in school starting age as an instrument for female’s age at first marriage and uses a regression discontinuity design to estimate its impact on female fertility. The statistical analysis based on the 2009 Nationwide Fertility Level and Family Health and Welfare Survey shows that an increase of one year in age at first marriage reduces the likelihood of any childbirth (extensive margin) by about 8 percentage points (10%) and total childbirths (intensive margin) by 0.1 children (6.3%). While delay in age at first marriage reduces fertility, we argue that policymakers should not implement policies to prevent females from delaying marriage timing as many studies have found that there are gains to delaying marriage. Rather, we argue that policymakers should engage more in identifying policy measures that allow the transition to adulthood and participation in higher-education institutions more compatible with motherhood and childbearing.
Background:
Fecundability (conception rate per menstrual cycle) varies among non-contracepting couples. Time-to-pregnancy studies can identify exposures contributing to that variability, using three designs: incident cohort, prevalent cohort, and retrospective. Typically, researchers then apply semi-parametric, generalized linear time-to-pregnancy models to data, with either a log or a logit "link," to estimate either a fecundability ratio (FR) or a fecundability odds ratio (FOR). The ongoing-attempt study design can also be informative.
Methods:
We consider a different generalized linear model, based on an inverse link. It models the heterogeneity as beta distributed and enables estimation of both the FR and FOR, defined based on population mean fecundabilities, without requiring constancy across attempt time. Under an ongoing-attempt design, the parameter associated with a dichotomous exposure has no clear meaning with a log or a logit link, but under the proposed approach estimates the ratio of the two average times to pregnancy. Basing simulations on conception rates from a large study, we compare the three analytic approaches for confidence interval coverage and power. We also assess the performance of a commonly used method for verifying the constancy of FOR or FR across time.
Results:
The inverse-link approach had slightly less power than the others, but its estimates maintained nominal confidence interval coverage under nonconstancy. A popular method for testing constancy across time for the FR and FOR had poor power.
Conclusions:
The inverse-link analysis offers a useful alternative to the usual methods, with estimation performance that generalizes to the ongoing-attempt design and does not require hard-to-verify constancy assumptions.
To study the age of the start of the fall (critical age) in fecundity; the probability of a pregnancy leading to a healthy baby taking into account the age of the woman; and, combining these results, to determine the age dependent probability of getting a healthy baby.
Cohort study of all women who had entered a donor insemination programme.
Two fertility clinics serving a large part of The Netherlands.
Of 1637 women attending for artificial insemination 751 fulfilled the selection criteria, being married to an azoospermic husband and nulliparous and never having received donor insemination before.
The number of cycles before pregnancy (a positive pregnancy test result) or stopping treatment; and result of the pregnancy (successful outcome).
Of the 751 women, 555 became pregnant and 461 had healthy babies. The fall in fecundity was estimated to start at around 31 years (critical age); after 12 cycles the probability of pregnancy in a woman aged greater than 31 was 0.54 compared with 0.74 in a woman aged 20.31. After 24 cycles this difference had decreased (probability of conception 0.75 in women greater than 31 and 0.85 in women 20.31). The probability of having a healthy baby also decreased--by 3.5% a year after the age of 30. Combining both these age effects, the chance of a woman aged 35 having a healthy baby was about half that of a woman aged 25.
After the age of 31 the probability of conception falls rapidly, but this can be partly compensated for by continuing insemination for more cycles. In addition, the probability of an adverse pregnancy outcome starts to increase at about the same age.
This report presents 1997 data on U.S. births according to a wide variety of characteristics. Data are presented for maternal demographic characteristics including age, live-birth order, race, Hispanic origin, marital status, and educational attainment; maternal lifestyle and health characteristics (medical risk factors, weight gain, and tobacco and alcohol use); medical care utilization by pregnant women (prenatal care, obstetric procedures, complications of labor and/or delivery, attendant at birth, and method of delivery); and infant health characteristics (period of gestation, birthweight, Apgar score, abnormal conditions, congenital anomalies, and multiple births). Also presented are birth and fertility rates by age, live-birth order, race, Hispanic origin, and marital status. Selected data by mother's State of residence are shown including teenage birth rates and total fertility rates, as well as data on month and day of birth, sex ratio, and age of father. Trends in fertility patterns and maternal and infant characteristics are described and interpreted.
Descriptive tabulations of data reported on the birth certificates of the 3.9 million births that occurred in 1997 are presented.
Birth and fertility rates declined very slightly in 1997. Birth rates for teenagers fell 3 to 5 percent. Rates for women in their twenties changed very little, whereas rates for women in their thirties rose 2 percent. The number of births and the birth rate for unmarried women each declined slightly in 1997 while the percent of births that were to unmarried women was unchanged. Smoking by pregnant women overall dropped again in 1997, but continued to increase among teenagers. Improvements in prenatal care utilization continued. The cesarean delivery rate increased slightly after declining for 7 consecutive years. The proportion of multiple birth continued to rise; higher order multiple births (e.g., triplets, quadruplets) rose by 14 percent in 1997, following a 20 percent rise from 1995 to 1996. Key measures of birth outcome--the percents of low birthweight and preterm births--increased, with particularly large increases in the preterm rate. These changes are in large part the result of increases in multiple births.
Objectives—This report presents 1998 data on U.S. births according to a wide variety of characteristics. Data are presented for maternal demographic characteristics including age, live-birth order, race, Hispanic origin, marital status, and educational attainment; maternal lifestyle and health characteristics (medical risk factors, weight gain, and tobacco and alcohol use); medical care utilization by pregnant women (prenatal care, obstetric procedures, complications of labor and/or delivery, attendant at birth, and method of delivery); and infant health characteristics (period of gestation, birthweight, Apgar score, abnormal conditions, congenital anomalies, and multiple births). Also presented are birth and fertility rates by age, live-birth order, race, Hispanic origin, and marital status. Selected data by mother’s State of residence are shown including teenage birth rates and total fertility rates, as well as data on month and day of birth, sex ratio, and age of father. Trends in fertility patterns and maternal and infant characteristics
This report presents detailed pregnancy rates for 1996 and 1997 to update a recently published comprehensive report on pregnancies and pregnancy rates for U.S. women.
Tabular and graphic data on pregnancy rates by age, race, and Hispanic origin, and by marital status are presented and described.
In 1997 an estimated 6.19 million pregnancies resulted in 3.88 million live births, 1.33 million induced abortions, and 0.98 million fetal losses. The 1997 pregnancy rate of 103.7 pregnancies per 1,000 women aged 15-44 years is the lowest recorded since 1976 (102.7), the first year for which a consistent series of national pregnancy rates is available. The 1997 rate was 10 percent lower than the peak rate in 1990 (115.6). The teenage pregnancy rate dropped steadily through 1997, falling to a record low of 94.3 pregnancies per 1,000 teenagers 15-19 years, 19 percent below the 1990 level (116.3). Rates for younger teenagers declined more than for older teenagers.
The increased risk of low birth weight associated with the use of assisted reproductive technology has been attributed largely to the higher rate of multiple gestations associated with such technology. It is uncertain, however, whether singleton infants conceived with the use of assisted reproductive technology may also have a higher risk of low birth weight than those who are conceived spontaneously.
We used population-based data to compare the rates of low birth weight (less-than-or-equal 2500 g) and very low birth weight (<1500 g) among infants conceived with assisted reproductive technology with the rates in the general population.
We studied 42,463 infants who were born in 1996 and 1997 and conceived with assisted reproductive technology and used as a comparison group 3,389,098 infants born in the United States in 1997. Among singleton infants born at 37 weeks of gestation or later, those conceived with assisted reproductive technology had a risk of low birth weight that was 2.6 times that in the general population (95 percent confidence interval, 2.4 to 2.7). The use of assisted reproductive technology was associated with an increased rate of multiple gestations; however, its use was not associated with a further increase in the risk of low birth weight in multiple births. Among twins, the ratio of the rate of low birth weight after the use of assisted reproductive technology to the rate in the general population was 1.0 (95 percent confidence interval, 1.0 to 1.1). Infants conceived with assisted reproductive technology accounted for 0.6 percent of all infants born to mothers who were 20 years of age or older in 1997, but for 3.5 percent of low-birth-weight and 4.3 percent of very-low-birth-weight infants.
The use of assisted reproductive technology accounts for a disproportionate number of low-birth-weight and very-low-birth-weight infants in the United States, in part because of absolute increases in multiple gestations and in part because of higher rates of low birth weight among singleton infants conceived with this technology.
In their target article “Strangers at the Benchside: Research Ethics Consultation,” Mildred Cho et al (2008) provide a useful overview of different approaches to research ethics consultation, the Stanford model of consultation, and some of the problems and concerns related to consultation. In this response, I will describe research ethics consultation at the National Institute of Environmental Health Sciences (NIEHS) and discuss some of the related to my work as a research ethics consultant.
Analytic methods for assessing the results of infertility therapy are reviewed and deficiencies discussed. A classification and staging scheme to define the type and severity of infertility problems is needed. Once homogeneous groups of patients are defined, the results of infertility therapy can be documented by the life-table method of analysis. A detailed description and format for this type of analysis are presented. To help conceptualize statistical probability as it pertains to infertility data, we have borrowed a mathematical model of fertility from demographers. This model can be used to predict the cumulative probability of conception over time, given a certain monthly probability of conception or fecundability. Also given that a couple has a certain duration of infertility, the model can be used to provide an estimate of an upper limit of the couple's likely monthly fecundability.
We omit the appendix, and sections of the paper discussing correlations between two successive conception delays and numerical results. (The maximum likelihood estimates for the mean and variance of fecundability, developed in the appendix, are the and V
p
given in our introduction to Henry, paper 41 above.)
There is increasing evidence that exposure to environmental toxins during key stages of development can disrupt the human reproductive system. Such effects have proven difficult to study due to the many behavioral and biological factors involved in human reproduction. We analyze data from a North Carolina fertility study to assess the effect of prenatal, childhood, and current cigarette smoking exposure on fecundability and sterility. We use a mixture model that adjusts for timing and frequency of intercourse and allows both fecundability and sterility to depend on multiple covariates. We account for dependency among menstrual cycles within individual couples using a mixture density for a latent cycle viability variable. The mixture consists of a normal distribution describing heterogeneity among fecund couples with a point mass at 0 for sterile couples. The resulting distribution is more biologically plausible than the standard beta density. A Markov chain Monte Carlo scheme is used for Bayesian estimation of the model. There is some evidence that spontaneous intrauterine mortality results in decreased fecundability in subsequent cycles. Both current cigarette smoking and prenatal exposure of the woman to her mother's cigarette smoking are shown to be associated with a decrease in the probability of menstrual cycle viability.
In this paper we examine the age pattern of sterility in a natural fertility population of 16 English parishes. We examine estimators of sterility proposed by historical demographers. We demonstrate through Monte Carolo simulation of reproductive histories that the estimators proposed earlier work well only if the ages to which the estimates pertain are substantially modified from the original formulation. The new estimates show a much larger positive effect of childbearing on sterility than would the earlier ones. We also present estimates of the age pattern of sterility due solely to the process of ageing by eliminating secondary sterility induced by childbearing. This curve rises slowly until age 40, after which the proportion sterile increases rapidly with age. We find no evidence of a sharp rise in the risk of sterility in the 30s. We find strong evidence of a decline in fecundity by examining age-specific fertility rates only for those women who are known to be fecund because they later bear children. The evidence suggests only a moderate decline until ages 35–39 and a much steeper decline thereafter.Finally, we illustrate the danger of the use of a clinical test of infertility commonly employed. We show that if women are judged to be infertile because they have not become pregnant within one year of unprotected exposure, then a large fraction of those so judged will be falsely diagnosed. We conclude that the one-year period is too short.
PIP
Lack of standardization in analytic methods for assigning infertility data is attributed to inadequate classification of fertility problems, and a lack of consistent methodology in evaluating outcome of infertility therapy. A classification scheme ideally should consider types of fertility problems as well as clinical assessment of its severity. Until an adequate classification system is developed, researchers are encouraged to describe fully the nature of infertility problem examined, and present results for homogenous groups of patients. The life-table method of analysis is a useful technique for assessing infertility statistics. The starting point of this method should depend on the group examined and may be either the date of 1st visit to the clinic or the date that therapy is instituted. Approximate date of conception should be the endpoint. A mathematical model of infertility predicated on the assumption that there is a constant monthly probability of conception of fecundability can be used to derive equations with potential for clinical application.
A new method for the estimation of the mean and variance of fecundability is described. The data input required for this procedure is the distribution of the interval from marriage to first birth, or from the resumption of the conception risk after contraction to the subsequent birth. The estimates of the mean and variance of fecundability are obtained by fitting a model to the observed interval distribution. To test the method, it is applied to data from five historical populations. The fecundability means in these populations ranged from 0.18 to 0.31 while the co-efficients of variation all had values near 0.56. A short method for the estimation of the mean of fecundability based on the same model, but not requiring a computer, is also presented.
To develop a simple estimation procedure that will always converge on a solution for a two-parameter model of cumulative pregnancy curves.
Utilize raw data from a previous study in which estimation of the two-parameter model did not converge on a solution, and re-estimate the model with the new estimation method. PATIENTS, SETTING, TREATMENT: Infertile women with endometriosis treated as outpatients with laser laparoscopy.
Pregnancy and ability of the new computer program to converge on a solution.
The new estimation procedure converged on a solution. Over all stages of endometriosis, the cure rate from laser laparoscopy was 56%, and the monthly probability of pregnancy among those cured was 9.7%.
The new estimation procedure, written for a personal computer, is easy to use and will virtually always converge on a solution for the two-parameter model of cumulative pregnancy after infertility treatment.
To determine the relationship between age and female fecundity, 210 women were studied prospectively. The subjects had negative infertility evaluations and were receiving therapeutic donor insemination. Life-table analysis was performed on 751 donor insemination cycles. For comparison, patients were divided into five separate age groups and into two separate groups, ages 19-34 and 35-45. Monthly fecundity and cumulative conception rates were calculated for each group. A significant difference was found when all age groups were compared (P = .05) and when those at or above age 35 and those below age 35 were compared (P less than .05). Frozen semen was used in 92% of all cycles. The average monthly fecundity of all patients treated with frozen semen was 16%. This study confirms a progressive decline in fecundity with age in a completely evaluated group of women undergoing therapeutic donor insemination and demonstrates that frozen semen can yield acceptable fecundity provided sufficient numbers of motile sperm are used for each procedure.
To gather data on sexuality, specifically in male veterans, and to test the hypothesis that aged males remain interested in sexual intercourse yet suffer from erectile failure, veterans age 30 to 99 were surveyed. The mailed survey had 88 questions and was pretested on young potent males and aged impotent males. From 1031 randomly selected subjects, there were 806 replies: 427 completed surveys, 247 refusals, and 132 who were too ill to participate (225 failed to reply). Among responders, sexual interest declined from a mean of 4.4/5 (4 = very interested, 5 = extremely interested) in men age 30-39 years to 2.0/5 (2 = slightly interested) in men age 90-99 (p less than 0.0001). Vaginal intercourse was consistently the preferred sexual activity; however, intercourse frequency was diminished from a mean of once per week in 30- to 39-year-olds to once per year in 90- to 99-year-olds (p less than 0.001). Frequency, rigidity, and duration of erections were less in aged compared to younger cohorts (p less than 0.0001). With these facts in mind, further research to bridge the libido-potency gap is warranted.
I assume the survival function of treated cancer patients to be a mixture of two subpopulations, with c equal to the proportion who will die of other causes, and 1--c the proportion who will die of their disease. Using census data, I estimate the parameters of the survival distribution of those patients dying of other causes, and then use follow-up data to determine the maximum likelihood estimates of the proportion constant c and the parameters of the survival function of those dying of their disease. I illustrate the methodology using data from a prospective clinical trial in breast cancer.
Time to pregnancy according to the age of the father and the mother has been studied among 10,886 couples from Odense and Aalborg. Late in their pregnancy (36th week) all woman in the two cities were given a questionnaire on time to pregnancy as well as a number of other items. Eighty-six percent responded to this questionnaire, and data concerning previous pregnancies, the outcome of the pregnancy in question, etc., were later collected from medical files. The study showed a strong correlation between mother's age and subfecundity, even after adjustment for a number of potential confounders. The association between subfecundity and the age of the father was much weaker and did not reach statistical significance. Interpretations and implications of these findings are discussed in the paper.
In this article, methods are presented for measuring the level and age pattern of sterility from incomplete birth histories, such as those that can be collected in demographic surveys of women who may not yet have reached the end of their reproductive span. The characteristics of the methods are examined in a simulation study that demonstrates that estimates based on information about fertility subsequent to a given age are more robust to variations in reproductive determinants, sample size, and sampling variation than the other measures, which include the frequently employed length of the open birth interval. In an illustrative analysis of World Fertility Survey data from sub-Saharan Africa, sterility was found to be high in Cameroon, intermediate in Lesotho and Sudan, and low in Ghana and Kenya relative to an English historical population.
A convenient measure of fecundability is time (number of menstrual cycles) required to achieve pregnancy. Couples attempting pregnancy are heterogeneous in their per-cycle probability of success. If success probabilities vary among couples according to a beta distribution, then cycles to pregnancy will have a beta-geometric distribution. Under this model, the inverse of the cycle-specific conception rate is a linear function of time. Data on cycles to pregnancy can be used to estimate the beta parameters by maximum likelihood in a straightforward manner with a package such as GLIM. The likelihood ratio test can thus be employed in studies of exposures that may impair fecundability. Covariates are incorporated in a natural way. The model is illustrated by applying it to data on cycles to pregnancy in smokers and nonsmokers, with adjustment for covariates. For a cross-sectional study, when length-biased sampling is taken into account, the pre-interview attempt time is shown to follow a beta-geometric distribution, so that the same methods of analysis can be applied even though all of the available data are right-censored. For a cohort followed prospectively, there will be some couples enrolled whose fecundability is effectively 0, and for such applications, the beta could be considered to be contaminated by a distribution degenerate at 0. The mixing parameter (proportion sterile) can be estimated by application of the expectation-maximization (EM) algorithm. This, too, can be carried out using GLIM.
Direct evidence on age patterns of infecundity and sterility cannot be obtained from contemporary populations because such large fractions of couples use contraception or have been sterilized. Instead, historical data are exploited to yield upper bounds applicable to contemporary populations on the proportions sterile at each age. Examination of recent changes in sexual behavior that may increase infecundity indicates that sexually transmitted infections, the prime candidate for hypothesized rises in infertility, are unlikely to have added to infecundity to any great extent. These results imply that a woman in a monogamous union faces only moderate increases in the probability of becoming sterile (or infecund) until her late thirties. Nevertheless, it appears that recent changes in reproductive behavior were guaranteed to result in the perception that infecundity is on the rise.
We analyzed a two- to seven-year follow-up of 1145 infertile couples to determine the frequency of pregnancy occurring independently of treatment. Pregnancy occurred in 246 of 597 treated couples (41 per cent) and in 191 of 548 untreated couples (35 per cent). Thirty-one per cent of the pregnancies in treated couples occurred more than 3 months after the last medical treatment or more than 12 months after adnexal surgery. These pregnancies plus the 191 pregnancies in untreated couples constituted the category of "treatment-independent pregnancies" and accounted for 61 per cent of all pregnancies; for 44 per cent of those among couples with ovulation deficiency; for 61 per cent of those in couples with endometriosis, tubal defects, or seminal deficiencies; and for 96 per cent of those in couples with cervical factors or idiopathic infertility. We conclude that the potential for a spontaneous cure of infertility is high, that treatment for many classes of infertility should be evaluated by randomized clinical trials, and that in such trials random assignment of subjects to untreated control groups would be ethically acceptable.
The decrease in the fecundity of women who have passed a certain age is generally acknowledged but supporting data on natural reproduction are scarce. Artificial insemination with donor semen (AID) seems to present an opportunity to control certain variables in the study of female fecundity over time, but the few studies published to date have been carried out in small populations. We studied 2193 women who were receiving AID and whose husbands were totally sterile. The curve of the cumulative success rate for the women 25 years of age or younger was similar to that for women 26 to 30 years old. However, this curve showed a significant decrease in the cumulative success rate for women 31 to 35 years of age. This decrease was even greater for those over 35. Similar decreases with age were observed for the mean conception rate per cycle. Our data therefore provide evidence of reduced fecundity with age, which begins at some point after the age of 30 years.
When evaluating the results of infertility therapy, it is often of interest to know whether differences exist between a new form of therapy and the established one, between medical and surgical therapy, or between patient groups that differ in severity of disease, age, parity, and so on. In this paper, a likelihood-ratio test is developed to evaluate differences between cumulative pregnancy curves of different patient groups. The test takes into account variation in patient follow-up and can be applied to any type of infertility therapy. It is illustrated by consideration of a group of patients who underwent artificial insemination by donor (AID) and determination of whether pregnancy outcome differed according to parity. It was found that the cure rate for both nulliparous and parous patients was virtually 100% and that the monthly probability of pregnancy was not significantly different between the two groups.
By establishing a statistical profile of the average sexual behaviour of women during the climacteric period, an attempt was made to determine what influence the climacteric had on female sexual activity. With the advancement of age, the sexual activity of women tends to decline. The menopause itself tends to further reduce the retrogression of the sexual activity in women.
The timing of sexual intercourse in relation to ovulation strongly influences the chance of conception, although the actual number of fertile days in a woman's menstrual cycle is uncertain. The timing of intercourse may also be associated with the sex of the baby.
We recruited 221 healthy women who were planning to become pregnant. At the same time the women stopped using birth-control methods, they began collecting daily urine specimens and keeping daily records of whether they had sexual intercourse. We measured estrogen and progesterone metabolites in urine to estimate the day of ovulation.
In a total of 625 menstrual cycles for which the dates of ovulation could be estimated, 192 pregnancies were initiated, as indicated by increases in the urinary concentration of human chorionic gonadotropin around the expected time of implantation. Two thirds (n = 129) ended in live births. Conception occurred only when intercourse took place during a six-day period that ended on the estimated day of ovulation. The probability of conception ranged from 0.10 when intercourse occurred five days before ovulation to 0.33 when it occurred on the day of ovulation itself. There was no evident relation between the age of sperm and the viability of the conceptus, although only 6 percent of the pregnancies could be firmly attributed to sperm that were three or more days old. Cycles producing male and female babies had similar patterns of intercourse in relation to ovulation.
Among healthy women trying to conceive, nearly all pregnancies can be attributed to intercourse during a six-day period ending on the day of ovulation. For practical purposes, the timing of sexual intercourse in relation to ovulation has no influence on the sex of the baby.
This paper develops a multistate hazards model for estimating fecundability and sterility from data on waiting times to conception. Important features of the model include separate sterile and nonsterile states, a distinction between preexisting sterility and sterility that begins after initiation of exposure, and log-normally distributed fecundability among nonsterile couples. Application of the model to data on first birth intervals from Taiwan, Sri Lanka, and the Amish shows that heterogeneity in fecundability is statistically significant at most ages, but that preexisting sterility and new sterility are unimportant before age 40. These results suggest that sterility may not be an important determinant of natural fertility until later reproductive ages.
This report shows data on a wide range of topics from the 1995 National Survey of Family Growth (NSFG), including: pregnancy and birth, marriage, divorce, cohabitation, sexual intercourse, contraception, infertility, use of family planning and other medical services, and health conditions and behavior.
The data in this report are based on in-person interviews with a national sample of 10,847 women 15-44 years of age. The interviews lasted an average of 103 minutes. The response rate was 79 percent. The sample data are adjusted for nonresponse and are national estimates.
Following large increases in the 1970's and 1980's, the proportion of teenagers who have ever had sexual intercourse decreased slightly between 1990 and 1995; condom use, both at first intercourse and currently, has increased markedly since the 1970's. These changes may have contributed to the decreases in the teen birth rate observed in the 1990's. For all women 15-44 years of age, the number whose partner was currently using the condom (at the date of interview) increased from 3.6 million in 1982 to 5.1 million in 1988 and 7.9 million in 1995. About 8 percent of women reported that their first intercourse was not voluntary. This result is consistent with an earlier national survey. About 20 percent reported that they had been forced by a man to have intercourse at some time in their lives. About 10 percent of births in 1990-95 were unwanted by the mother compared with 12 percent in 1984-88. The decrease in unwanted births was particularly large for black women. It appears that the prevalence of pelvic inflammatory disease (PID) and vaginal douching have both decreased since 1988.
To compare the obstetric characteristics of singleton pregnancies conceived by IVF and ovulation induction with those conceived spontaneously.
Case-control study.
Tertiary care medical center.
All singleton pregnancies that were achieved by IVF (n = 169) and ovulation induction (n = 646) and were delivered from January 1989 through December 1994 were evaluated. Each group was compared with a separate control group that conceived spontaneously (n = 469 and n = 1,902 for the IVF and ovulation induction groups, respectively) and delivered during the same period and was matched in terms of maternal age, gestational age, and parity.
Ovulation induction, IVF-ET. Main Outcome Measure(s): Obstetric complications.
Multivariate analysis showed that patients who conceived by IVF and ovulation induction had a significantly higher risk for gestational diabetes mellitus (odds ratio [OR] = 2.0; 95% confidence interval [CI] = 1.23-3.30 and OR = 1.9, 95% CI = 1.09-1.79, respectively), pregnancy-induced hypertension (OR = 2.1, 95% CI = 1.04-4.10 and OR = 1.5, 95% CI = 1.04-2.02, respectively), and cesarean section (OR = 3.6, 95% CI = 2.44-5.29 and OR = 1.4, 95% CI = 1.09-1.79, respectively) compared with their matched controls.
After controlling for maternal age, gestational age, and parity, we demonstrated that singleton pregnancies conceived by IVF and ovulation induction are at increased risk for maternal gestational diabetes mellitus and pregnancy-induced hypertension, and at greater risk for delivery by cesarean section.
Two studies have related the timing of sexual intercourse (relative to ovulation) to day-specific fecundability. The first
was a study of Catholic couples practising natural family planning in London in the 1950s and 1960s and the second was of
North Carolina couples attempting to become pregnant in the early 1980s. The former identified ovulation based on the ovulatory
shift in the basal body temperature, while the latter used urinary assays of hormones. We use a statistical model to correct
for error in identifying ovulation and to re-estimate the length of the fertile window and day-specific fecundabilities. We
estimate the same 6-day fertile interval in both studies after controlling for error. After adjusting for error both data
sets showed the highest estimate of the probability of pregnancy on the day prior to ovulation and both fell close to zero
after ovulation. Given that the fertile interval is before ovulation, methods that anticipate ovulation by several days (such
as the assessment of cervical mucus) would be particularly useful for couples who want to time their intercourse either to
avoid or facilitate conception.
Time to pregnancy studies that identify ovulation days and collect daily intercourse data can be used to estimate the day-specific probabilities of conception given intercourse on a single day relative to ovulation. In this article, a Bayesian semiparametric model is described for flexibly characterizing covariate effects and heterogeneity among couples in daily fecundability. The proposed model is characterized by the timing of the most fertile day of the cycle relative to ovulation, by the probability of conception due to intercourse on the most fertile day, and by the ratios of the daily conception probabilities for other days of the cycle relative to this peak probability. The ratios are assumed to be increasing in time to the peak and decreasing thereafter. Generalized linear mixed models are used to incorporate covariate and couple-specific effects on the peak probability and on the day-specific ratios. A Markov chain Monte Carlo algorithm is described for posterior estimation, and the methods are illustrated through application to caffeine data from a North Carolina pregnancy study.
There is an absence of population-based long-term studies on the risk of neurological sequelae in children born after in-vitro fertilisation (IVF). Our aim was to compare the frequency of such problems between IVF-born children and controls.
We did a population-based retrospective cohort study in which we compared development of neurological problems in 5680 children born after IVF, with 11360 matched controls. For 2060 twins born after IVF, a second set of controls (n=4120), all twins, were selected. We obtained data on neurological problems from the records of the Swedish habilitation centres.
Children born after IVF are more likely to need habilitation services than controls (odds ratio 1.7, 95% CI 1.3-2.2). For singletons, the risk was 1.4 (1.0-2.1). The most common neurological diagnosis was cerebral palsy, for which children born after IVF had an increased risk of 3.7(2.0-6.6), and IVF singletons of 2.8 (1.3-5.8). Suspected developmental delay was increased four-fold (1.9-8.3) in children born after IVF. Twins born after IVF did not differ from control twins with respect to risk of neurological sequelae. Low-birthweight and premature infants were more likely to need habilitation than fullterm babies. Maternal age did not affect risk.
Our study suggests that children born after IVF have an increased risk of developing neurological problems, especially cerebral palsy. These risks are largely due to the high frequency of twin pregnancies, low birthweight, and prematurity among babies born after IVF. To limit these risks, we recommend that only one embryo should be transferred during IVF.
It is not known whether infants conceived with use of intracytoplasmic sperm injection or in vitro fertilization have a higher risk of birth defects than infants conceived naturally.
We obtained data from three registries in Western Australia on births, births after assisted conception, and major birth defects in infants born between 1993 and 1997. We assessed the prevalence of major birth defects diagnosed by one year of age in infants conceived naturally or with use of intracytoplasmic sperm injection or in vitro fertilization.
Twenty-six of the 301 infants conceived with intracytoplasmic sperm injection (8.6 percent) and 75 of the 837 infants conceived with in vitro fertilization (9.0 percent) had a major birth defect diagnosed by one year of age, as compared with 168 of the 4000 naturally conceived infants (4.2 percent; P<0.001 for the comparison between either type of technology and natural conception). As compared with natural conception, the odds ratio for a major birth defect by one year of age, after adjustment for maternal age and parity, the sex of the infant, and correlation between siblings, was 2.0 (95 percent confidence interval, 1.3 to 3.2) with intracytoplasmic sperm injection, and 2.0 (95 percent confidence interval, 1.5 to 2.9) with in vitro fertilization. Infants conceived with use of assisted reproductive technology were more likely than naturally conceived infants to have multiple major defects and to have chromosomal and musculoskeletal defects.
Infants conceived with use of intracytoplasmic sperm injection or in vitro fertilization have twice as high a risk of a major birth defect as naturally conceived infants.
Most analyses of age-related changes in fertility cannot separate effects due to reduced frequency of sexual intercourse from effects directly related to ageing. Information on intercourse collected daily through each menstrual cycle provides the data for estimating day-specific probabilities of pregnancy for specific days relative to ovulation, and these estimates allow unconfounded analysis of ageing effects.
A total of 782 healthy couples using natural family planning methods contributed prospective data on 5860 menstrual cycles. Day of ovulation was based on basal body temperature measurements. Estimates of day-specific probabilities of pregnancy and the length of the fertile window were compared across age groups.
Nearly all pregnancies occurred within a 6 day fertile window. There was no evidence for a shorter fertile window in older men or women. On average, the day-specific probabilities of pregnancy declined with age for women from the late 20s onward, with probabilities of pregnancy twice as high for women aged 19-26 years compared with women aged 35-39 years. Controlling for age of the woman, fertility was significantly reduced for men aged >35 years.
Women's fertility begins to decline in the late 20s with substantial decreases by the late 30s. Fertility for men is less affected by age, but shows significant decline by the late 30s.
This multicenter study has produced a database of 7017 menstrual cycles contributed by 881 women. It provides improved knowledge on length and location of the "fertile window" (identified as of up to 12 days duration) and the patterns and level of daily conception probability. The day of ovulation was identified in each cycle from records of basal body temperature and mucus symptoms. By referencing days of intercourse to the surrogate ovulation markers, estimates of daily fecundability were computed either directly or by the Scwartz model, both for single and multiple acts of intercourse in the fertile window. The relationship between coital pattern and fecundability has been explored. Univariate analysis underlines the significant link with fecundability only of the woman's reproductive history.
To assess the day-specific and cycle-specific probabilities of conception leading to clinical pregnancy, in relation to the timing of intercourse and vulvar mucus observations.
This was a retrospective cohort study of women beginning use of the Creighton Model Fertility Care System in Missouri, Nebraska, Kansas, and California. Data were abstracted from Creighton Model Fertility Care System records, including women's daily standardized vulvar observations of cervical mucus discharge, days of intercourse, and clinically evident pregnancy (conception). Established statistical models were used to estimate day-specific probabilities of conception.
Data were analyzed from 1681 cycles with 81 conceptions from 309 normally fertile couples (initially seeking to avoid pregnancy) and from 373 cycles with 30 conceptions from 117 subfertile couples (who were initially trying to achieve pregnancy). The highest probability of pregnancy occurred on the peak day of vulvar mucus observation (.38 for normally fertile couples and.14 for subfertile couples). The probability of pregnancy was greater than.05 for normally fertile couples from 3 days before to 2 days after the peak, and for subfertile couples from 1 day before to 1 day after the peak. The cycle-specific probability of conception correlated with the quality of mucus discharge in normally fertile couples but not in subfertile couples.
Standardized vulvar observations of vaginal mucus discharge identify the days with the greatest likelihood of conception from intercourse in normal fertility and subfertility and provide an indicator of the overall potential for conception in a given menstrual cycle in normal fertility.
We propose several Bayesian models for modelling time-to-event data. We consider a piecewise exponential model, a fully parametric cure rate model and a semiparametric cure rate model. For each model, we derive the likelihood function and examine some of its properties for carrying out Bayesian inference with non-informative priors. We also examine model identifiability issues and give conditions which guarantee identifiability. Also, for each model, we construct a class of informative prior distributions based on historical data, i.e. data from similar previous studies. These priors, called power priors, prove to be quite useful in this context. We examine the properties of the power priors for Bayesian inference and, in particular, we study their effect on the current analysis. Tools for model comparison and model assessment are also proposed. A detailed case-study of a recently completed melanoma clinical trial conducted by the Eastern Cooperative Oncology Group is presented and the methodology proposed is demonstrated in detail.
This multicentre study has produced a database of 7017 menstrual cycles contributed by 881 women. It provides improved knowledge on length and location of the "fertile window" (identified as of up to 12 days duration) and the pattern and level of daily conception probability. The day of ovulation was identified in each cycle from records of basal body temperature and mucus symptoms. By referencing days of intercourse to the surrogate ovulation markers, estimates of daily fecundability were computed either directly or by the Schwartz model, both for single and multiple acts of intercourse in the fertile window. The relationship between coital pattern and fecundability has been explored. Univariate analysis underlines the significant link with fecundability only of the woman’s reproductive history.
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- Ca Bachrach
- Mc Horn
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- J Trussell
- U Larsen
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Married and unmarried couples, United States
- C A Bachrach
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- J A Collins
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