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. 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. 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). 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.

Social support has been proposed as an important determinant of women's physical and emotional well-being during pregnancy and after childbirth. Our study aimed to examine the association between the risk of postpartum depression (PPD) and perceived social support during pregnancy. A web-based prospective study survey was conducted among Polish women. The level of social support was measured with the Berlin Social Support Scales during pregnancy. Four weeks after the birth the risk of PPD was assessed using the Edinburgh Postpartum Depression Scale. Data from 932 mothers aged 19–43 (mean 30.95; SD 3.83) were analyzed using multinomial logistic regression. Higher perceived available support (emotional and instrumental), currently received support (emotional, instrumental and informational), satisfaction with the support, and sum of score were all associated with lower risk of PPD, after controlling for selected covariates (woman's age, socioeconomic status, parity status, place of residency, education, child's Apgar score, type of delivery, complications during birth, kin assisting the labor, breastfeeding). Our results suggest that the more social support the pregnant woman receives, the lower is her risk of PPD. Since humans evolved as cooperative breeders, they are inherently reliant on social support to raise children and such allomaternal help could improve maternal well-being.

Perinatal maternal anxiety and depression negatively affect intrauterine fetal development, birth outcome, breastfeeding initiation, duration, and milk composition. Antenatal classes potentially reduce the anxiety of pregnant women and may thus contribute to healthy infant development. The study investigates the relationship between participation in online or in-person antenatal classes and levels of anxiety and depression in Polish women during the COVID-19 pandemic. The study group included 1774 adult, non-smoking pregnant women. We compared the state anxiety (STAI-State) and depression levels (EPDS) in women who (i) attended antenatal classes in-person, (ii) attended online classes, and (iii) did not attend any of them. The statistical analyses included a GLM model and trend analysis, while controlling for maternal trait anxiety, age, pregnancy complications, trimester of pregnancy, previous pregnancies, and COVID-19 infections. We observed statistically significant differences in the level of anxiety (and depression). Women who did attend antenatal classes in person had the lowest levels of anxiety and depression. Considering the importance of maternal mental well-being on fetal development, birth outcome, and breastfeeding, in-person participation in antenatal classes should be recommended to pregnant women.