Testosterone during pregnancy and gender role behavior of preschool children: a longitudinal, population study.

Levels of testosterone (T) and sex hormone-binding globulin (SHBG) were measured in blood samples from pregnant women and related to gender role behavior in 342 male and 337 female offspring at the age of 3.5 years. Gender role behavior was assessed using the Pre-School Activities Inventory, a standardized measure on which a parent indicates the child's involvement with sex-typical toys, games, and activities. Levels of T, but not SHBG, related linearly to gender role behavior in preschool girls. Neither hormone related to gender role behavior in boys. Other factors, including the presence of older brothers or sisters in the home, parental adherence to traditional sex roles, the presence of a male partner in the home, and maternal education, did not relate to gender role behavior in this sample and did not account for the relation observed between T and behavior. Although other, unmeasured factors may explain the relation, the results suggest that normal variability in T levels prenatally may contribute to the development of individual differences in the gender role behavior of preschool girls.

Prenatal stress and gender role behavior in girls and boys: a longitudinal, population study.

Prenatal stress influences neural and behavioral sexual differentiation in rodents. Male offspring of stressed pregnancies show reduced masculine-typical characteristics and increased feminine-typical characteristics, whereas female offspring show the opposite pattern, reduced feminine-typical and increased masculine-typical characteristics. These outcomes resemble those seen following manipulations of gonadal hormones and are thought to occur because stress influences these hormones during critical periods of development. Research on prenatal stress and human sexual differentiation has produced inconsistent results, perhaps because studies have used small samples and assessed prenatal stress retrospectively. We related maternal self-reports of prenatal stress to childhood gender role behavior in a prospective, population study of 13,998 pregnancies resulting in 14,138 offspring. Neither stress reported during the first 18 weeks of pregnancy nor stress reported from week 19 of pregnancy to week 8 postnatal related to gender role behavior in male offspring at the age of 42 months. In female offspring, maternal reports of stress during both periods showed only small correlations with masculine-typical behavior. Although this relationship remained significant when other factors that related to stress were controlled, these other factors made larger contributions to girls' gender role behavior than did prenatal stress. In addition, in both boys and girls, older male or female siblings, parental adherence to traditional sex roles, maternal use of tobacco or alcohol during pregnancy, and maternal education all related significantly to gender role behavior. Our results suggest that prenatal stress does not influence the development of gender role behavior in boys and appears to have relatively little, if any, influence on gender role behavior in girls.