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Background: Cervical cancer (CxCa), although preventable, is still among the most prevalent cancers in women. Mortality from this cancer is high, especially in low-income countries where preventive strategies are often lacking. We studied the knowledge, attitudes, and practices regarding CxCa among Yemeni women. Methods: This cross-sectional study was conducted in 2019 among 399 women in five major hospitals in Sanaa, the capital city of Yemen. Data were collected through face-to-face interviews using structured questionnaires. We used logistic regression models to analyze the likelihood of hearing about CxCa, believing that CxCa is treatable and preventable, awareness of the Pap smear test, and ever having this test, in relation to participant's age, education level, working outside the household, and family history of CxCa. Results: Only 66.7% of the women had heard of CxCa. Women with higher education, working outside the household, and with a family history of CxCa were more likely to be aware of CxCa. Working outside the household was the only variable related to a higher likelihood of knowing that CxCa is a treatable and preventable. Furthermore, women with a family history of CxCa were more likely to have knowledge about Pap smear test and were more likely to have Pap smear test in the past. Conclusion: This study identified a low awareness of CxCa and its prevention among Yemeni women. In order to reduce the burden of CxCa in Yemen and save women's lives, it is necessary to raise women's awareness of this disease, especially among those with lower education and those not involved in work outside their homes. [ABSTRACT FROM AUTHOR]

Objectives: Sex steroid hormones are important not only for reproduction but also for many aspects of women's health, including the risk of breast cancer. Physical activity has been shown to influence sex hormone levels in women. This study aimed to investigate a relationship between the average daily number of steps and the sex hormone (estradiol and progesterone) levels in premenopausal women. Materials and methods: Data were collected from 85 healthy, urban women of reproductive age who performed at least 180 minutes/week of moderate physical activity for two complete menstrual cycles. Physical activity was measured using wrist bands. Estradiol and progesterone concentrations were measured in daily-collected saliva samples in the second menstrual cycle. Results: There was a significant negative association between the average number of steps taken daily and salivary progesterone levels after adjusting for potential confounding factors (age, BMI). Women who took more than 10,000 steps a day had significantly lower progesterone levels compared to women who took less than 10,000 steps. The association between physical activity and estradiol levels was statistically insignificant. Discussion: Our results indicate that taking at least 10,000 steps a day reduces progesterone levels, but this intensity of physical activity may not be high enough to affect estradiol levels. Daily step tracking is a valuable element of health promotion, but currently recommended levels of physical activity may not be high enough for healthy premenopausal women to significantly reduce both sex hormone levels and thus their risk of postmenopausal breast cancer. [ABSTRACT FROM AUTHOR]

Urinary tract infections (UTIs) are the most common infections experienced by women. Previously, scalp and facial hair in men have been shown to inhibit the growth of pathogenic bacteria. Here we hypothesize that having hairy genitalia might protect women from UTI. This study investigated grooming habits and occurrence of UTIs in the past 12 months in 2409 women (aged 18–45). Women who reported removing all their pubic hair at least weekly were defined as extreme groomers (66.8%). We collected additional information on covariates including age, having a first UTI at or before age 15, spermicide use, having a new sex partner, and frequency of sexual intercourse during the past year. Extreme grooming was not associated with the risk of being diagnosed with UTI (OR = 1.17, 95% CI = 0.90–1.52), but was associated with a higher risk of recurrent UTIs, defined as three or more UTIs within 12 months (OR = 3.09, 95% CI = 1.35–7.06), after controlling for age, history of UTIs, and sexual practices. Other studies have found that hygienic purposes are the most common motivations for pubic hair removal. These results suggest that along with their pubes, women may be getting rid of important microbial niche and protection against recurrent UTIs. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to test the hypothesis that ethnic and ethnolinguistic discrimination, and Post‐Traumatic Stress Disorder (PTSD) related to being Indigenous as well as different aspects of acculturative stress, are associated with poorer health and higher levels of depression among the Nahua Indigenous communities. Materials and methods: Our quantitative survey was carried out in four different regions inhabited by the Nahua people in Mexico. Self‐rated health and depression, the symptoms of PTSD, two facets of acculturative stress and ethnolinguistic discrimination were assessed by questionnaires. The data were analyzed using binary logistic regression models. Results: The symptoms of PTSD and acculturative stress experienced in the workplace were significantly associated with a higher risk of poor self‐rated health, adjusted for various socio‐demographic characteristics. Acculturative stress, discouragement of language use, language avoidance and ethnolinguistic discrimination were related to a higher risk of depression and PTSD. Discussion: Our research implies that ethnic and linguistic discrimination, acculturative stress and the memory of harm linked to being Indigenous reflected in the symptoms of PTSD, are important predictors of poorer health and depression among Nahua groups in Mexico. These adverse effects could be significantly counteracted by effective dealing with stigmatization and discrimination against Indigenous people in Mexico and by replacing strong assimilation pressures with integrational approaches that respect ethnolinguistic diversity and reduce socioeconomic marginalization. [ABSTRACT FROM AUTHOR]

One of the most crucial determinants of early-life development is the experience of childhood adversities. However, limited evidence is available for how these experiences shape later-life reproductive outcomes in women. Here we test the association between early-life adversities and reproductive parameters in women. Post-reproductive women (N = 105; mean age = 59.7; SD = 10.09) were recruited at the Mogielica Human Ecology Study Site in Poland within a traditional population with a low prevalence of birth control usage and fully traced reproductive histories. Reproductive parameters, as well as exposure to early-life abuse and neglect, were assessed using questionnaires. Childhood adversity was associated negatively with age at menarche (p = 0.009). Analyses on specific subtypes revealed that compared to women who did not experience any kind of early-life adversities in childhood, those who were exposed to emotional (p = 0.007) and physical (p = 0.023) neglect had an earlier age at menarche, those who experienced emotional abuse reported an earlier age at first birth (p = 0.035), and those who were exposed to physical abuse gave birth to fewer number of sons (p = 0.010). Our results suggest that women exposed to childhood adversities experience earlier physiological reproductive readiness and timing of the first birth, but their overall biological condition might be impaired as they bear fewer sons. [ABSTRACT FROM AUTHOR]

Objectives: The level of fluctuating asymmetry is suggested as a putative signal of developmental stability, thus according to this theoretical framework more symmetric individuals should be in better biological condition and have greater reproductive potential. Here we hypothesize that women with more symmetric faces have more successful reproduction. Methods: Data were collected from 164 postmenopausal Polish women. Facial photographs were taken and the overall facial asymmetry (OFA) was calculated. The associations between the OFA and reproductive parameters were analyzed using multiple regression models. Furthermore, the mediation analysis was conducted to test for the indirect effects of the OFA on reproductive success. Results: There was a statistically significant relationship between the OFA and the number of children born, which was mediated by the age at first reproduction (p = 0.03), however, the size of the effect was rather low. Women with more symmetric faces had an earlier age at first reproduction and, in consequence, a greater number of children. Discussion: As fluctuating asymmetry is suggested to be established in utero, these findings shed light on the possible life‐long importance of developmental conditions in shaping women's reproductive potential and performance. [ABSTRACT FROM AUTHOR]

Differences in attitudes on social issues such as abortion, immigration and sex are hugely divisive, and understanding their origins is among the most important tasks facing human behavioural sciences. Despite the clear psychological importance of parenthood and the motivation to provide care for children, researchers have only recently begun investigating their influence on social and political attitudes. Because socially conservative values ostensibly prioritize safety, stability and family values, we hypothesized that being more invested in parental care might make socially conservative policies more appealing. Studies 1 (preregistered; n = 376) and 2 (n = 1924) find novel evidence of conditional experimental effects of a parenthood prime, such that people who engaged strongly with a childcare manipulation showed an increase in social conservatism. Studies 3 (n = 2610, novel data from 10 countries) and 4 (n = 426 444, World Values Survey data) find evidence that both parenthood and parental care motivation are associated with increased social conservatism around the globe. Further, most of the positive association globally between age and social conservatism is accounted for by parenthood. These findings support the hypothesis that parenthood and parental care motivation increase social conservatism. [ABSTRACT FROM AUTHOR]

Objectives: Multiple macronutrients have been shown to affect systemic inflammation, a well‐known predictor of chronic disease. Less often, varying sources of these macronutrients are examined. Different subsistence environments lead to varying access to protein sources which, combined with physical activity patterns, may lead to different relationships than among more typically studied sedentary, industrialized populations. This study hypothesizes an association between dietary protein intake and urinary C‐reactive protein (CRP) concentration in women from a rural, agrarian Polish community. Materials and Methods: We assessed protein intake and their sources for 80 nonsmoking, premenopausal Polish women who were not pregnant, nursing, or on hormonal birth control during the study or within the previous 6 months. Each participant completed multiple 24‐hr dietary recalls during one menstrual cycle. Participants collected morning void urinary samples daily over one menstrual cycle for urinary CRP analysis. We analyzed relationships between plant and animal protein intake and CRP over the menstrual cycle by multiple linear regression. Results: Plant protein in cereal foods was significantly positively associated with cycle‐average urinary CRP concentrations (p < 0.05) after controlling for body fat percent, total energy intake, and dietary fiber. Foods containing animal protein were not significantly associated with CRP. Discussion: Contents of this population's main plant and animal protein sources differ from those of more commonly studied industrialized populations. Within the context of a population's typical diet, more emphasis may need to be placed on particular source of protein consumed, beyond plant versus animal, in order to understand relationships with CRP. [ABSTRACT FROM AUTHOR]

Background: Human milk oligosaccharides (HMOs) are an abundant class of compounds found in human milk and have been linked to the development of the infant, and specifically the brain, immune system, and gut microbiome.Objectives: Advanced analytical methods were used to obtain relative quantitation of many structures in approximately 2000 samples from over 1000 mothers in urban, semirural, and rural sites across geographically diverse countries.Methods: LC-MS-based analytical methods were used to profile the compounds with broad structural coverage and quantitative information. The profiles revealed their structural heterogeneity and their potential biological roles. Comparisons of HMO compositions were made between mothers of different age groups, lactation periods, infant sexes, and residing geographical locations.Results: A common behavior found among all sites was a decrease in HMO abundances during lactation until approximately postnatal month 6, where they remained relatively constant. The greatest variations in structural abundances were associated with the presence of α(1,2)-fucosylated species. Genomic analyses of the mothers were not performed; instead, milk was phenotyped according to the abundances of α(1,2)-fucosylated structures. Mothers from the South American sites tended to have higher proportions of phenotypic secretors [mothers with relatively high concentrations of α(1,2)-fucosylated structures] in their populations compared to the rest of the globe, with Bolivia at ∼100% secretors, Peru at ∼97%, Brazil at ∼90%, and Argentina at ∼85%. Conversely, the cohort sampled in Africa manifested the lowest proportion of secretors (South Africa ∼ 63%, the Gambia ∼ 64%, and Malawi ∼ 75%). Furthermore, we compared total abundances of HMOs in secretors compared with nonsecretors and found that nonsecretors have lower abundances of HMOs compared to secretors, regardless of geographical location. We also observed compositional differences of the 50+ most abundant HMOs between milk types and geographical locations.Conclusions: This study represents the largest structural HMO study to date and reveals the general behavior of HMOs during lactation among different populations. [ABSTRACT FROM AUTHOR]

Background: Although relationships between exposure to air pollution and reproductive health are broadly studied, mechanisms behind these phenomena are still unknown. The aim of the study was to assess whether exposure to particulate matter (PM10) and tobacco smoking have an impact on menstrual profiles of 17β-estradiol (E2) and progesterone (P) and the E2/P ratio. Methods: Levels of sex hormones were measured daily in saliva during the entire menstrual cycle among 132 healthy, urban women. Exposure to smoking (active or passive) was assessed by questionnaire, whilst exposure to PM10 with municipal monitoring data. Results: During the early luteal phase, profiles of E2 were elevated among women with higher versus lower exposure to PM10 (p = 0.02, post-hoc tests). Among those who were exposed versus unexposed to tobacco smoking, the levels of mean E2 measured during the entire cycle were higher (p = 0.02). The difference in mean E2 levels between the group of joint exposure (i.e. to high PM10 and passive or active smoking) versus the reference group (low PM10, no smoking) was statistically significant at p = 0.03 (18.4 vs. 12.4 pmol/l, respectively). The E2/P ratios were higher among women with higher versus lower exposure to PM10 and this difference was seen only in the early luteal phase (p = 0.01, exploratory post-hoc tests). Conclusions: We found that PM10 and tobacco smoking affect ovarian hormones independently and do not interact with each other. Both exposures appear to have estrogenic effects even though women's susceptibility to these effects differs across the menstrual cycle. We propose that the hormonal mechanisms are involved in observed relationships between air pollution and smoking with women's reproductive health. [ABSTRACT FROM AUTHOR]

Background: Although relationships between exposure to air pollution and reproductive health are broadly studied, mechanisms behind these phenomena are still unknown. The aim of the study was to assess whether exposure to particulate matter (PM10) and tobacco smoking have an impact on menstrual profiles of 17β-estradiol (E2) and progesterone (P) and the E2/P ratio. Methods: Levels of sex hormones were measured daily in saliva during the entire menstrual cycle among 132 healthy, urban women. Exposure to smoking (active or passive) was assessed by questionnaire, whilst exposure to PM10 with municipal monitoring data. Results: During the early luteal phase, profiles of E2 were elevated among women with higher versus lower exposure to PM10 (p = 0.02, post-hoc tests). Among those who were exposed versus unexposed to tobacco smoking, the levels of mean E2 measured during the entire cycle were higher (p = 0.02). The difference in mean E2 levels between the group of joint exposure (i.e. to high PM10 and passive or active smoking) versus the reference group (low PM10, no smoking) was statistically significant at p = 0.03 (18.4 vs. 12.4 pmol/l, respectively). The E2/P ratios were higher among women with higher versus lower exposure to PM10 and this difference was seen only in the early luteal phase (p = 0.01, exploratory post-hoc tests). Conclusions: We found that PM10 and tobacco smoking affect ovarian hormones independently and do not interact with each other. Both exposures appear to have estrogenic effects even though women's susceptibility to these effects differs across the menstrual cycle. We propose that the hormonal mechanisms are involved in observed relationships between air pollution and smoking with women's reproductive health. [ABSTRACT FROM AUTHOR]

Objectives: Oxidative stress is hypothesized to contribute to age‐related somatic deterioration. Both reproductive and ecological context may necessitate tradeoffs that influence this outcome. We examined whether measures of lifetime reproductive effort were related to levels of oxidative stress biomarkers in peri‐ and post‐menopausal women and whether associations were moderated by rural or urban residence. Methods: We surveyed 263 healthy women (age 62.1 ± 10.0 SD) from rural (N = 161) and urban Poland (N = 102), collecting sociodemographic data and urine samples to analyze biomarkers of oxidative stress (8‐oxo‐2′‐deoxyguanosine, 8‐OHdG) and antioxidative defense (copper‐zinc superoxide dismutase, Cu‐Zn SOD). Linear regression models, adjusted for residence, were used to test for associations between reproductive effort and 8‐OHdG and Cu‐Zn SOD. Results: Univariate models demonstrated significant associations between gravidity and the biomarkers of oxidative stress (8‐OHdG: R2 = 0.042, P ≤.001; Cu‐Zn SOD: R2 = 0.123, P ≤.001). Multivariate models incorporating potential confounding variables, as well as cross‐product interaction terms, indicated that gravidity was associated with 8‐OHdG (P <.01, R2adj = 0.067) and Cu‐Zn SOD (P =.01, R2adj = 0.159). Residence (ie, urban vs rural) did not significantly moderate the associations between the biomarkers and reproductive effort. Conclusions: Higher lifetime reproductive effort contributes to increases in oxidative stress and antioxidative defenses. Our results provide evidence of potential mechanisms underlying the physiological tradeoffs influencing senescence for women with high reproductive effort. We illustrate the value of applying an evolutionary perspective to elucidate variation in human health and senescence. [ABSTRACT FROM AUTHOR]

Objective: Early‐life conditions play an important role in human development, affecting health status and survival. Conditions in utero partly depend on the external environment and thus vary in relation to the season of birth. The aim of this study was to investigate if people born in different seasons of the year differ in values of biomarkers that reflect conditions during fetal development. Methods: The study was conducted among Polish rural women recruited at the Mogielica Human Ecology Study Site. The participants were 234 women aged 45 to 92 (mean = 60.2; SD = 10.44). The indicators of early‐life environment analyzed in the study were: Absolute Finger Ridge Count (AFRC), the difference between mean number of ridge counts in both thumbs and both little fingers (Md15), overall facial fluctuating asymmetry (OFA), central facial asymmetry (CFA), right and left hand 2D:4D. Results: Values of biomarkers of fetal development did not vary among groups of women born in different seasons of the year. Conclusions: Lack of differences in values of biomarkers according to birth season may indicate that: (a) season of birth is not a good indicator of early‐life conditions; (b) tested biomarkers do not reliably reflect the prenatal environment; (c) season of birth does not fully overlap with the sensitive periods of biomarker development and thus fails to capture differences in developmental conditions. [ABSTRACT FROM AUTHOR]

Objectives: Reproduction is costly, but sons and daughters differently influence maternal physiology, also in older age. In particular, having sons may negatively influence maternal health and may be associated with a shorter life span of mothers. Sons may also contribute to increased inflammaging, a chronic sub‐clinical systemic inflammatory state characterized by elevated levels of serum inflammatory mediators. The aim of this study was to examine the impact of the total number of children, and the number of daughters and sons separately on concentrations of C‐reactive protein (CRP), and proinflammatory cytokines such as interleukin 6 (IL‐6) and tumor necrosis factor‐α (TNF‐α). Materials and Methods: The participants were 378 women aged 45–92 who had 3.9 (SD 2.12, median = 4, range = 0–13) children, including 2.1 (SD 1.46, median = 2, range = 0–8) sons and 1.8 (SD 1.44, median = 2, range = 0–7) daughters on average. Results: We found a positive relationship between the overall number of children and IL‐6 levels. CRP and IL‐6 concentrations were positively associated with the number of sons but not with the number of daughters. Each son increased maternal CRP level by 11%, and IL‐6 level by 6%. Neither the total number of children nor the number of daughters or sons were related to the TNF‐α concentration. Discussion Aging‐associated inflammation in post‐reproductive mothers with a higher number of sons supports the hypothesis of trade‐offs between reproduction and health. Furthermore, these results provide new evidence contributing to the idea that having sons may have more detrimental effects on the maternal organism than having daughters. [ABSTRACT FROM AUTHOR]

Objectives: Digit ratio (2D:4D) is widely used as a biomarker of prenatal hormonal environment linked to the growing number of adult health and disease‐related characteristics. It has been suggested that 2D:4D is a good predictor of cardiovascular diseases (CVD) risk among men, but results in women are still inconclusive. Here we test the relationship between 2D:4D and the incidence of cardiovascular diseases (CVD), and their risk factors in Polish, rural women. Methods: The participants were 410 women age 50 and older. Structured questionnaire was used to gather personal and medical data, including the history of CVD diagnosed by a medical doctor. Anthropometric measurements of body height, weight, and finger lengths were performed. Right‐hand and left‐hand 2D:4D, mean 2D:4D, Dl‐r, and BMI were calculated afterward. For a subgroup of participants (n = 329) fasting blood sample was collected (in order to assess the lipid profile and glucose levels) and blood pressure was measured. Age, education level and BMI were included as potential covariates. Results: No statistically significant association was observed between 2D:4D markers and the incidence of CVD (eg, heart attack, stroke) or CVD risk factors (dyslipidaemia, dysglycaemia or hypertension), when controlled for age, education and BMI. Conclusions: The results of our study add to the growing number of studies investigating the sex‐difference of the association between 2D:4D and cardiac health. We conclude that from a public health perspective 2D:4D may not be a valuable biomarker of elevated risk of CVDs in women. [ABSTRACT FROM AUTHOR]

The emotion of disgust is suggested to be an adaptation that evolved to keep us away from sources of infection. Therefore, individuals from populations with greater pathogen stress should have a greater disgust sensitivity. However, current evidence for a positive relationship between disgust sensitivity and the intensity of infectious diseases in the environment is limited. We tested whether disgust and contamination sensitivity changed in response to the COVID-19 pandemic. Disgust was assessed in 984 women in 2017 (before pandemic) and 633 women in 2020 (during pandemic) by a set of photographs depicting sources of infection and Pathogen and Moral of Three-Domain Disgust Scale. Further, contamination sensitivity among participants in two waves was measured by Contamination Obsessions and Washing Compulsions Subscale of Padua Inventory. State anxiety was measured with the Polish adaptation of the State-Trait Anxiety Inventory (STAI) only during the second wave of data collection. Women from the COVID-19 pandemic group assessed the photographs depicting sources of infection as more disgusting, scoring higher on Padua Inventory, but lower on Moral Disgust Domain as compared to women from before the pandemic. In addition, anxiety levels during pandemic positively correlated with scores from Pathogen Disgust Domain, Padua Inventory, and the ratings of the photographs. The participants of the study scored higher in state anxiety than the norms determined for the Polish population. Summarizing, we present evidence for differences in individual levels of disgust sensitivity in relation to pathogen stress, supporting the idea that disgust evolved to serve as protection from pathogens. [ABSTRACT FROM AUTHOR]

Objective: Bone mineral density (BMD) and frame size are important predictors of future bone health, with smaller frame size and lower BMD associated with higher risk of later fragility fractures. We test the effects of body size, habitual use, and life history on frame size and cortical BMD of the radius and tibia in sample of healthy adult premenopausal women. Methods: We used anthropometry and life history data from 123 women (age 18‐46) from rural Poland. Standard techniques were used to measure height, weight, and body fat. Life history factors were recorded using surveys. Grip strength was measured as a proxy for habitual activity, wrist breadth for skeletal frame size. Cortical BMD was measured at the one‐third distal point of the radius and mid‐point of the tibia using quantitative ultrasound (reported as speed of sound, SoS). Results: Radial SoS was high (mean t‐score 3.2 ± 1.6), but tibia SoS was average (mean t‐score 0.35 ± 1.17). SoS was not associated with age, although wrist breadth was positively associated with age after adjusting for height. Radius SoS was not associated with measures of body size, habitual use, or life history factors. Wrist breadth was associated with body size (p <.05 for all), lean mass, and grip strength. Tibia SoS was associated with height. Life history factors were not associated with frame size or cortical SoS. Conclusions: Habitual use and overall body size are more strongly associated with frame size and cortical SoS than life history factors in this sample of healthy adult women. [ABSTRACT FROM AUTHOR]

Objectives: Fetal environmental conditions are crucial for life‐long health. Direct measurements of developmental conditions are limited in humans; thus, several biomarkers of those conditions have been proposed: that is, finger ridge‐counts, level of facial fluctuating asymmetry (FA), and digit ratio (2D:4D). Since all of these biomarkers share a similar gestational time of formation, we hypothesize that their values are significantly correlated. Materials and methods: Data were collected at the Mogielica Human Ecology Study Site in southern Poland among 234 women. Finger ridge‐counts, level of facial FA, and 2D:4D have been measured. The two‐step analyses included Pearson's correlations of simple values of the biomarkers and correlations of composite variables calculated based on principal component analysis. Results: We did not find any statistically significant correlations between finger ridge‐counts, FA, and 2D:4D in women. Similarly, we did not observe any correlations between three composites created from the biomarkers. Discussion Our results indicate that there are no relationships between the biomarkers, suggested as proxies of the quality of prenatal conditions, in a single population. This is the first study analyzing three different markers simultaneously. The lack of correlations may indicate that the tested biomarkers reflect, in fact, different environmental conditions, occurring in separate "critical windows" of development, or that the biomarkers are not valid as proxies of developmental conditions. [ABSTRACT FROM AUTHOR]

Perceived facial attractiveness, a putative marker of high biological fitness, is costly to maintain throughout a lifetime and may cause higher oxidative stress (OS). We investigated the association between the facial features of 97 postmenopausal women and their levels of OS biomarkers 8-hydroxy-2′-deoxyguanosine (8-OHdG), superoxide dismutase (Cu-Zn SOD), and thiobarbituric acid reactive substances (TBARS). In study 1, 966 judges rated the composites (facial averages) of women with higher OS as more attractive, healthier, younger, and less symmetric. In study 2, Geometric Morphometric analysis did not reveal significant differences in facial morphology depending on OS levels. In study 3, measured facial averageness and symmetry were weakly negatively related to 8-OHdG levels. Maintaining higher perceived facial attractiveness may be costly due to increased oxidative damage in the postmenopausal period. These costs may remain hidden during the reproductive period of life due to the protective mechanisms of oxidative shielding and revealed only after menopause when shielding has ceased. [ABSTRACT FROM AUTHOR]

Evolutionary theories of ageing point to reproduction as a significant factor to consider when asking why ageing occurs and why there is inter-individual variation in its progression. Reproduction in human females is costly, in terms of energy, nutrients and metabolic adjustments. Thus, it is expected that women who experienced high reproductive effort resulting from multiple reproductive events will age faster. However, the evidence for long-term negative effects of reproduction is not conclusive. The lack of understanding of whether there are trade-offs between reproduction and ageing in women is partly due to methodological challenges. The costs of reproduction are often calculated based only on parity, while other elements contributing to these costs (e.g. breastfeeding, timing of reproduction) are neglected, which may significantly underestimate the total costs and obscure the all-important inter-individual variation in such costs. Costs must be evaluated in relation to individual characteristics, including developmental conditions, nutritional status and social support that a mother receives during reproduction. Furthermore, ageing and health must be assessed based on comprehensive markers rather than arbitrarily assembled variables. Finally, longitudinal rather than cross-sectional studies and new statistical approaches are needed to reveal how much of a decline in health and progressing ageing can actually be attributed to past reproductive processes. This article is part of the theme issue 'Evolution of the primate ageing process'. [ABSTRACT FROM AUTHOR]

Objective: Age at menarche in Poland has varied with political and socioeconomic changes. An increase in age at menarche corresponded to a period of economic crisis and food rationing between 1976 and 1989. Experiencing food shortages in utero or during childhood development can affect menarcheal timing, but this national effect may be buffered in local agrarian regions growing their own food. Here we examine patterns of age at menarche over time in the rural, agrarian Beskid Wyspowy region of southern Poland. Methods: This study examined menarcheal timing using data collected from Polish women (n = 1326) recruited at the Mogielica Human Ecology Study Site between 2003 and 2018. Simple linear regressions were used to assess changing ages at menarche over time. Comparisons between ages at menarche for women born before and after the fall of communism in 1989 were assessed via one‐way analysis of variance. Results: Age at menarche has declined over time in the Beskid Wyspowy region of southern Poland from 1920 to 2000 (R2 =.08, P <.0001). There was not a statistically significant increase or decrease in age at menarche for women born and growing up during the period of food rationing. Conclusions: The declining age at menarche is likely reflective of a transitioning environment, suggesting that major socioeconomic changes affect life history traits like pubertal timing. Living in agricultural regions may have helped buffer the increasing ages at menarche seen in other areas of Poland during times of food rationing. [ABSTRACT FROM AUTHOR]

Life‐history theory predicts that access to limited resources leads to trade‐offs between competing body functions. Women, who face higher costs of reproduction when compared to men, should be especially vulnerable to these trade‐offs. We propose the 'cognitive costs of reproduction hypothesis', which states that energy trade‐offs imposed by reproduction may lead to a decline in maternal cognitive function during gestation. In particular, we hypothesize that the decline in cognitive function frequently observed during pregnancy is associated with the allocation of resources between the competing energetic requirements of the mother's brain and the developing foetus. Several distinctive anatomical and physiological features including a high metabolic rate of the brain, large infant size, specific anatomical features of the placenta and trophoblast, and the lack of maternal control over glucose flow through the placenta make the occurrence of these trade‐offs likely. Herein, we review several lines of evidence for trade‐offs between gestation and cognition that are related to: (i) energy metabolism during reproduction; (ii) energy metabolism of the human brain; (iii) links between energy metabolism and cognitive function; and (iv) links between gestation and cognitive function. We also review evidence for the important roles of cortisol, corticotropin‐releasing hormone and sex hormones in mediating the effects of gestation on cognition, and we discuss possible neurophysiological mechanisms underlying the observed effects. The evidence supports the view that energy trade‐offs between foetal growth and maternal endocrine and brain function lead to changes in maternal cognition, and that this phenomenon is mediated by neuroendocrine mechanisms involving the hypothalamic–pituitary–adrenal axis, brainstem nucleus locus coeruleus and hippocampus. [ABSTRACT FROM AUTHOR]

High investment in reproductive processes at the expense of other physiological functions may result in poor maternal health. Health status at older age can be reliably assessed by self-rated health, which is a strong predictor of mortality. We investigated trade-offs between reproduction and health by analysing relationships between self-rated health and the total number of children ever born by a woman, and the number of her sons and daughters among 559 post-reproductive women aged 45-92 from Poland. The number of sons, but not the number of daughters or the total number of children, was significantly associated with self-rated health, adjusted to potential confounders (age, education, marital status, current smoking, and body mass index). Each son increased the odds of reporting poor health by 11% (odds ratio = 0.89; 95% confidence interval = 0.81-0.99). Sons are more energetically and immunologically demanding for the maternal organism which may explain why having sons has more negative influence on maternal health in older age than having daughters. In order to understand trade-offs between reproduction and maternal health not only the total number of children but also sex of the children should be taken into account. [ABSTRACT FROM AUTHOR]

The influence of sex hormones on women’s mate preferences has been an intensively discussed topic for more than a decade. Yet the extent to which levels of sex hormones, and testosterone in particular, influence women’s mate preferences is unclear. Thus, the current study used multilevel modelling to investigate putative relationships between salivary testosterone and facial masculinity preferences in a sample of 68 women, while controlling for their age, partnership status, and sociosexuality. We found no significant associations between masculinity preferences and either individual differences or within-woman changes in testosterone. We did find however, that sociosexuality was positively correlated with masculinity preferences. Although it has previously been suggested that testosterone is related to women’s facial masculinity preference, our data do not support this proposal. [ABSTRACT FROM AUTHOR]

According to life-history theory, paternal investment affects the well-being of offspring. We hypothesized that environmental stress caused by a lack of paternal investment may diminish maternal resource allocation during pregnancy, especially for women who already have dependent children. Our study was conducted on a representative group of more than 80,500 singleton, live-born, full-term infants born in Krakow, Poland in the period 1995–2009. Birth data were obtained from the birth registry. We found that missing data about fathers (a proxy measure of low paternal investment) was associated with higher probability of multiparous mothers giving birth to low-birth-weight infants (1.48; 95% CI 1.05–2.08), but this was not the case with primiparous mothers (1.19; 95% CI 0.89–1.59). The statistically significant synergistic effect between parity and paternal investment was found (Synergy Factor = 2.12; 95% CI 1.47–3.05, p<0.001). These findings suggest that in situations of low paternal investment, multiparous mothers face trade-offs between investing in existing versus unborn children, therefore investment in the latter is lower. Such a strategy may benefit maternal fitness due to investment in older children, who have higher reproductive value. [ABSTRACT FROM AUTHOR]

Women show cyclical shifts in preferences for physical male traits. Here we investigated how fertility status influences women's facial masculinity preference in men by analyzing a large sample of heterosexual women (N = 3720). Women were regularly either cycling (in both low- and high-conception probability groups), lactating or were currently in a non-fertile state (pregnant or post-menopausal). Analyses simultaneously controlled for women's age and sexual openness. Participants via two alternative forced choice questions judged attractiveness of masculinized and feminized men's faces. After controlling for the effect of age and sociosexuality, regularly cycling and pregnant women showed a stronger preference for masculinity than lactating and post-menopausal women. However, there was no significant difference in masculinity preference between women in the low- and high-conception probability groups. Women's sociosexuality showed a positive, but very weak association with men's facial masculinity preference. We suggest that women's overall, long-term hormonal state (cycling, post-menopausal) is a stronger predictor of preference for sexual dimorphism than changes in hormonal levels through the cycle. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: Among couples, women usually prefer slightly older men, and men tend to choose much younger partners. Age difference between partners has been shown to influence their parity; however, results of previous studies are inconsistent. This study analyzed relationships between husband and wife age difference and their total number of children, and number of daughters and sons in a contemporary, rural Polish population. Methods: Demographic and reproductive data were collected from 384 postmenopausal women from rural Poland who were married only once. Regression models were used to evaluate the impact of the age gap between partners on total number of children and on number of daughters and sons. Women's age, age at marriage (as an indicator of reproductive value), and years of education were used in analyzes as potential confounders. Results: There was an inverted U‐shape association between parental age difference and number of children and also the number of sons. The highest number of children and sons was observed when men were approximately 6.5 years older than their wives. There was no significant relationship between parental age difference and number of daughters. Conclusions: Age difference between partners is important for reproductive success (with younger wives having higher reproductive potential) and is also related to number of sons. Older husbands might provide more resources for the family, thus facilitating production of well‐nourished male offspring. Future research should evaluate not only number of children but also their biological condition, health, and lifetime achievements in relation to the age difference between their parents. [ABSTRACT FROM AUTHOR]

Objectives: The costs associated with reproduction (i.e., gestation, lactation, childcare) have longterm negative consequences by elevating risk of disease and reducing lifespan. We tested the hypotheses that high parity, and thus high reproductive costs bear by women, is perceived by other people when they evaluate facial appearance of health, attractiveness and age of mothers. Materials and Methods: Using computer software we created average facial images based on real photographs of post-menopausal women with varying number of children; 3 parity categories were created (1-2, 4-5, and 7-9 children). Study participants (N=571) were asked to choose the face they perceived as more attractive, younger and healthier via two-alternative forced choice questions asked in three randomized blocks. Results: Women who had given birth to fewer children were judged both by men and women as more attractive, younger and healthier than women with more children. In each category the lowest scores were received by women from highest parity category (7-9 children). Discussion: Mechanisms behind the observed variation in facial appearance are not known but higher levels of oxidative stress among women with high parity may explain their faster aging and lower attractiveness in older age. These results suggest that costs of reproduction might affect women's physical appearance. [ABSTRACT FROM AUTHOR]

Lay Summary: Adaptive immune proteins in mothers' milk are more variable than innate immune proteins across populations and subsistence strategies. These results suggest that the immune defenses in milk are shaped by a mother's environment throughout her life. Background and objectives: Mother's milk contains immune proteins that play critical roles in protecting the infant from infection and priming the infant's developing immune system during early life. The composition of these molecules in milk, particularly the acquired immune proteins, is thought to reflect a mother's immunological exposures throughout her life. In this study, we examine the composition of innate and acquired immune proteins in milk across seven populations with diverse disease and cultural ecologies. Methodology: Milk samples (n = 164) were collected in Argentina, Bolivia, Nepal, Namibia, Philippines, Poland and the USA. Populations were classified as having one of four subsistence patterns: urban-industrialism, rural-shop, horticulturalist-forager or agro-pastoralism. Milk innate (lactalbumin, lactoferrin and lysozyme) and acquired (Secretory IgA, IgG and IgM) protein concentrations were determined using triple-quadrupole mass spectrometry. Results: Both innate and acquired immune protein composition in milk varied among populations, though the acquired immune protein composition of milk differed more among populations. Populations living in closer geographic proximity or having similar subsistence strategies (e.g. agropastoralists from Nepal and Namibia) had more similar milk immune protein compositions. Agropastoralists had different milk innate immune protein composition from horticulturalist-foragers and urban-industrialists. Acquired immune protein composition differed among all subsistence strategies except horticulturist-foragers and rural-shop. Conclusions and implications: Our results reveal fundamental variation in milk composition that has not been previously explored in human milk research. Further study is needed to understand what specific aspects of the local environment influence milk composition and the effects this variation may have on infant health outcomes. [ABSTRACT FROM AUTHOR]

Human milk contains essential micronutrients for growth and development during early life. Environmental pollutants, such as potentially toxic metals, can also be transferred to the infant through human milk. These elements have been well-studied, but changing diets and environments and advances in laboratory technology require re-examining these elements in a variety of settings. The aim of this study was to characterize the concentrations of essential and toxic metals in human milk from four diverse populations. Human milk samples (n = 70) were collected in Argentina (n = 21), Namibia (n = 6), Poland (n = 23), and the United States (n = 20) using a standardized mid-feed collection procedure. Milk concentrations of calcium, zinc, iron, copper, manganese, lead, arsenic, and cadmium were determined using inductively coupled plasma mass spectrometry (ICP-MS). We used standard multiple linear regression models to evaluate differences among populations, while including infant age, infant sex, and maternal parity status (multiparous or primiparous) as covariates. Concentrations of all elements, except zinc, varied across populations after controlling for infant age, infant sex, and maternal parity. Calcium and magnesium showed more differences across populations than iron or copper. There were no significant differences among population in zinc concentrations. Mean concentrations of lead, but not arsenic, were low compared to recently published values from other populations. The concentrations of trace elements in human milk are variable among populations. Limitations due to small sample sizes and environmental contamination of some samples prevent us from drawing robust conclusions about the causes of these differences. [ABSTRACT FROM AUTHOR]

Multiparous mothers have greater umbilical blood flow and thus more efficient transport of pollutants than primiparous mothers. We tested a hypothesis that multiparous mothers are more prone to have an infant with low birth weight (LBW) after prenatal exposure to air pollution. A study was conducted on a representative group of more than 74,000 singleton, live, full-term infants. Birth data were obtained from the birth registry, while pollution data were from an environmental monitoring system (Poland). Multiple comparisons were controlled by the false discovery rate procedure (FDR). After standardization, the harmful effect of carbon monoxide (CO) on the odds ratio (OR) for LBW was seen among the multiparous mothers (OR = 1.28; 95% CI 1.06–1.54), while in primiparous mothers it was nonsignificant. The effect of CO on the OR for LBW differed according to parity, which was confirmed by the test for interaction (FDR-adjustedp = 0.03). The interaction between parity and sulfur dioxide (SO2) was statistically nonsignificant (FDR-adjustedp = 0.08). Multiparous mothers may be more vulnerable to CO than primiparous mothers. Parity may be the modifier of the association between pollutants and the risk of LBW. [ABSTRACT FROM PUBLISHER]

Author Correction: From January to June: Birth seasonality across two centuries in a rural Polish community "This work was supported by the National Science Centre [grant number 2016/21/D/NZ8/01306 (IN)]; the Ministry of Science and Higher Education [grant number IdP2011000161 (GJ)]; and the Ella & Georg Ehrnrooth Foundation (MB)." now reads: "This work was supported by the National Science Centre [grant number 2016/21/D/NZ8/01306 (IN)]; the Ministry of Science and Higher Education [grant number IdP2011000161 (GJ)]; and the Ella & Georg Ehrnrooth Foundation (MB). Publication of this article was funded by the Priority Research Area qLife under the program "Excellence Initiative - Research University" at the Jagiellonian University in Krakow (06/IDUB/2019/94).". [Extracted from the article]

Objectives: Prenatal development has a long-lasting influence on biological condition and health. Second-tofourth digit ratio (2D:4D) is suggested as an indicator of sex hormone exposure during fetal development, and it is likely that women with a more feminine digit ratio were exposed to higher prenatal estrogen levels. Therefore, we tested if 2D:4D was related to a woman's reproductive characteristics. Methods: We studied 319 women aged 46-92, who went through a natural menopause and whose husbands were alive at least until their menopause were studied. Women were recruited at the Mogielica Human Ecology Study Site located in rural Poland. Results: Women with more feminine 2D:4D had a higher number of children (P = 0.002), gave birth to their last child at a later age (P = 0.02), and had a longer reproductive lifespan (P = 0.04) than women with more masculine 2D:4D. Age and number of years of education were included as potential confounders in the analyses. Conclusions: The results indicated that women with more feminine 2D:4D had higher reproductive success. While the exact mechanisms were not known, and the relationship between 2D:4D and adult sex hormone levels was questioned by previous studies, there might be other biological pathways explaining the observed results, that is, via behaviors that were indirectly related to fertility. [ABSTRACT FROM AUTHOR]

Life history theory predicts trade-offs between reproductive effort and maternal survivorship in energy-restricted environments. However, empirical evidence for the positive association between maternal mortality and reproductive effort from energetically challenged human populations are mixed and physiological mechanisms that may underlie this association are poorly understood. We hypothesized that increases in aerobic metabolism during repeated periods of pregnancy and lactation result in increased oxidative stress that may contribute to somatic deterioration, vulnerability to illness, and accelerated aging. We therefore predicted that lifetime gravidity and parity would be related to levels of biomarkers of oxidative stress, as well as antioxidative defence enzymes in post-menopausal women. Our hypothesis was supported by positive linear associations between levels of 8-OHdG, a biomarker of DNA oxidative damage (β = 0.21, p<0.05), levels of antioxidative defence enzyme Cu-Zn SOD (β = 0.25, p<0.05), and number of lifetime pregnancies. Furthermore, independent of age and health status, post-menopausal women with higher gravidity and parity (> = 4 pregnancies per lifetime) had 20% higher levels of 8-OHdG and 60% higher levels of Cu-Zn SOD compared to women with lower gravidity and parity (<4 pregnancies per lifetime). Our results present the first evidence for oxidative stress as a possible cost of reproductive effort in humans. [ABSTRACT FROM AUTHOR]

Objectives Short interpregnancy intervals (IPI) and high parity may be synergistically associated with the risk of unfavorable pregnancy outcomes. This study tests if the effect of short IPI on the odds ratio for low birth weight (LBW, <2,500 g) differs across parity status. Methods The study was carried out on the birth registry sample of almost 40,000 singleton, live-born infants who were delivered between the years 1995 and 2009 to multiparous mothers whose residence at the time of infant's birth was the city of Krakow. Multiple logistic regression analyses were used for testing the effect of IPI on the odds ratio (OR) for LBW, after controlling for employment, educational and marital status, parity, sex of the child, maternal and gestational age. Stratified analyses (according to parity) and tests for interaction were performed. Results Very short IPI (0-5 months) was associated with an increased OR for LBW, but only among high parity mothers with three or more births (OR = 2.64; 95% CI 1.45-4.80). The test for interaction between very short IPI and parity on the OR for LBW was statistically significant after adjustment for multiple comparisons ( P = 0.04). Among low parity mothers (two births) no statistically significant associations were found between IPI and LBW after standardization. Conclusion Parity may modify the association between short birth spacing and LBW. Women with very short IPI and high parity may have a higher risk of having LBW infants than those with very short IPI but low parity. Am. J. Hum. Biol. 27:660-666, 2015. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Objectives Second-to-fourth digit ratio (2D:4D) is proposed as a proxy for the prenatal balance of sex hormones, is related to hormone-dependent characteristics in adult life, and is a possible predictor of disease later in life. Here, we studied the relationship between 2D:4D and ovarian steroid hormones (17β-estradiol and progesterone) among women of reproductive age. Methods From 186 healthy premenopausal women, aged 24-37 years, we collected saliva samples daily during the entire menstrual cycle. Data on reproductive and lifestyle characteristics were collected via questionnaires, and anthropometric measurements were performed. Results No statistically significant relationships were detected between adult women's sex hormone concentrations (17β-estradiol and progesterone) during the menstrual cycle and 2D:4D, in either left or right hand, when controlling for size at birth, body mass index, and physical activity. Conclusions This study shows, for the first time in a large sample of women of reproductive age, that 2D:4D is not a predictor of adult women's sex hormone concentration. The lack of relationship may be because 2D:4D might be genetically determined and is not related to maternal nutritional environment during fetal development. These results support the hypothesis that, in contrast to the nutritional quality of the fetal environment, the fetal hormonal environment (reflected by 2D:4D) does not determine reproductive physiology in later life. Am. J. Hum. Biol. 27:666-673, 2015. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Objectives Testosterone supports male reproduction through a broad range of behavioral and physiological effects, including the maintenance of sexually dimorphic muscle used in male-male competition. Although it is often assumed that a persistent relationship exists between men's testosterone production and musculature, most studies either fail to find evidence for such a relationship, or document very weak associations. In nonhuman primates, by contrast, correlations between testosterone and muscle mass are higher. Here, we propose the 'Paternal Provisioning Hypothesis,' which predicts that men's skeletal muscle is less dependent on the effects of androgens than that of other primates, and more sensitive to the physical demands of men's work. This permits human fathers to downregulate testosterone, which has negative impacts on pair-bonding and parenting effort, but without sacrificing the strength and musculature necessary to provision mates and offspring. Methods We tested predictions of the Paternal Provisioning Hypothesis by assessing parental status, salivary testosterone levels, anthropometry, and strength among 122 men (ages 18-78) at the Mogielica Human Ecology Study Site in rural Poland. We chose this population because men practice subsistence agriculture, regularly engaging in physically demanding labor. Grip and chest strength were assessed using a dynamometer, and upper-body musculature was estimated from arm muscle circumference. Results In this population, testosterone showed no association with measures of strength or musculature, and was lower in older men and pair-bonded fathers. Marital and parental status and workload, by contrast, were positive predictors of muscle mass and strength measures. Discussion These findings offer support for the Paternal Provisioning Hypothesis. Am J Phys Anthropol 158:19-35, 2015. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Introduction: Alcohol consumption may promote aromatization of androgens to estrogens, which may partly explain the observations linking alcohol consumption to higher breast cancer risk. Whether alcohol consumption is associated with endogenous estrogen levels, and mammographic density phenotypes in premenopausal women remains unclear. Methods: Alcohol consumption was collected by self-report and interview, using semi quantitative food frequency questionnaires, and a food diary during seven days of a menstrual cycle among 202 premenopausal women, participating in the Energy Balance and Breast Cancer Aspects (EBBA) study I. Estrogen was assessed in serum and daily in saliva across an entire menstrual cycle. Computer-assisted mammographic density (Madena) was obtained from digitized mammograms taken between days 7–12 of the menstrual cycle. Multivariable regression models were used to investigate the associations between alcohol consumption, endogenous estrogen and mammographic density phenotypes. Results: Current alcohol consumption was positively associated with endogenous estrogen, and absolute mammographic density. We observed 18 % higher mean salivary 17β-estradiol levels throughout the menstrual cycle, among women who consumed more than 10 g of alcohol per day compared to women who consumed less than 10 g of alcohol per day (p = 0.034). Long-term and past-year alcohol consumption was positively associated with mammographic density. We observed a positive association between alcohol consumption (past year) and absolute mammographic density; high alcohol consumers (≥7 drinks/week) had a mean absolute mammographic density of 46.17 cm2 (95 % confidence interval (CI) 39.39, 52.95), while low alcohol consumers (<1 drink/week) had a mean absolute mammographic density of 31.26 cm2 (95 % CI 25.89, 36.64) (p-trend 0.001). After adjustments, high consumers of alcohol (≥7 drinks/week), had 5.08 (95 % CI 1.82, 14.20) times higher odds of having absolute mammographic density above median (>32.4 cm2), compared to low (<1 drink/week) alcohol consumers. Conclusion: Alcohol consumption was positively associated with daily endogenous estrogen levels and mammographic density in premenopausal women. These associations could point to an important area of breast cancer prevention. [ABSTRACT FROM AUTHOR]

Objectives: The 2nd to 4th digit ratio (2D:4D) is thought to reflect exposure to androgens during foetal development. This study examined the relationship between low (more masculine) and high (more feminine) 2D:4D and body size at different stages of the life course, adult testosterone levels and number of children among males. Methods: Five hundred and fifty-eight men from rural Poland at the Mogielica Human Ecology Study Site participated in this study. Life history data and anthropometric measurements were collected. Salivary morning and evening testosterone levels among 110 men from the same population were measured. Results: Low 2D:4D was related to higher birth weight ( p = 0.04), higher birth length ( p = 0.01), higher body mass during childhood and adolescence ( p = 0.01), higher BMI (borderline significance, p = 0.06), higher number of children among fathers ( p = 0.04) and higher testosterone levels during adulthood ( p = 0.04). Conclusions: This study shows, for the first time in a single population, that digit ratio is related to sub-adult body size at different stages of the life course, adult testosterone levels and number of children. The observed results suggest that digit ratio might be a valuable predictor of male body size and reproductive characteristics. [ABSTRACT FROM AUTHOR]

Since the late 1990s, scholars have advocated for the adoption of political-economic approaches in biological anthropology. Despite this, the explicit application of these perspectives remains relatively rare. In this paper we argue for greater investment in this field of inquiry and advocate linking evolutionary-developmental and political-economic approaches to the study of human biology. We begin by discussing the historical development of human biology and the emergence of biocultural approaches in biological and medical anthropology. We then discuss evolutionary approaches grounded in phenotypic plasticity as an important framework for linking culture and biology. Finally, we consider the implications of culture theory based in political economy for building and expanding biocultural models. In particular, we examine the importance of inequality in structuring access to the means of cultural production and the creation of self-reinforcing norms. We finish with a discussion of the implications of these conclusions for future research. [ABSTRACT FROM AUTHOR]

Explaining why fertility declines as populations modernize is a profound theoretical challenge. It remains unclear whether the fundamental drivers are economic or cultural in nature. Cultural evolutionary theory suggests that community-level characteristics, for example average education, can alter how low-fertility preferences are transmitted and adopted. These assumptions have not been empirically tested. Here, we show that community-level education accelerates fertility decline in a way that is neither predicted by individual characteristics, nor by the level of economic modernization in a population. In 22 high-fertility communities in Poland, fertility converged on a smaller family size as average education in the community increased� indeed community-level education had a larger impact on fertility decline than did individual education. This convergencewas not driven by educational levels being more homogeneous, but by less educated women having fewer children than expected, and more highly educated social networks, when living amongmore highly educated neighbours. The average level of education in a community may influence the social partners women interact with, both within and beyond their immediate social environments, altering the reproductive norms they are exposed to. Given a critical mass of highly educated women, less educated neighbours may adopt their reproductive behaviour, accelerating the pace of demographic transition. Individual characteristics alone cannot capture these dynamics and studies relying solely on them may systematically underestimate the importance of cultural transmission in driving fertility declines. Our results are inconsistent with a purely individualistic, rational-actor model of fertility decline and suggest that optimization of reproduction is partly driven by cultural dynamics beyond the individual. [ABSTRACT FROM AUTHOR]

Objectives To test the hypothesis that life history trade-offs between maintenance and reproductive effort would be evident through inverse associations between levels of a biomarker of inflammation [C-reactive protein (CRP)], and ovarian hormones. Associations between CRP and age at menarche were also explored. Methods Urinary CRP, salivary progesterone, and estradiol were measured over one menstrual cycle from rural Polish women ( n = 25), representing a natural fertility sample. Age of menarche was assessed through interview recall methods. We used minimum second-order Akaike Information Criteria as a means of multiple regression model selection, and repeated measures ANOVA to test cycle-dependent hypotheses. Results Comparisons of individuals in high and low CRP tertiles revealed that those with high CRP had significantly lower progesterone (luteal P = 0.03, mid luteal P = 0.007) but not estradiol (follicular P = 0.21, luteal P = 0.15) concentrations through the menstrual cycle. However, when the age at menarche was included in the analysis, both age at menarche and urinary CRP were negatively associated with estradiol ( R2 = 0.44, P = 0.0007). Age at menarche and estradiol were the strongest negative predictors of CRP ( R2 = 0.52, P = 0.0001). Conclusions Inflammation itself may suppress ovarian function, or indicate immune challenges that lead to ovarian suppression. The timing of menarche may also influence adult inflammatory sensitivity and ovarian hormone concentrations. This lends support to existing models of trade-offs between maintenance and reproduction in women. Am. J. Hum. Biol. 25:389-398, 2013. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]