Early androgens and development of social personality traits: Evidence from classical congenital adrenal hyperplasia

Experimental studies in nonhuman species have demonstrated the powerful effects of androgen exposure during early life on neurobehavioral development. Work also has demonstrated links between early androgens in humans and characteristics that show sex differences, such as childhood play, gender identity, and sexual orientation. This study extends the investigation of potential androgen influences to the development of a subset of personality traits that are relevant to social interaction. We investigated the relationship of early androgens to personality traits, assessed via questionnaires, that show average sex differences (overall aggression, physical aggression, dominance, and tender-mindedness/sensitivity). Participants, average age of 30.2 years, included 33 women and 20 men with classical congenital adrenal hyperplasia (CAH), which leads to elevated androgen concentrations in females prenatally, and an equal number of well-matched controls. Data supported the hypotheses that (1) control men show higher personality traits of aggression and dominance, and lower tender-mindedness/sensitivity than control women; (2) Women with CAH show more male-typical and less female-typical traits in each personality domain compared to control women; but (3) men with CAH do not differ from control men. These data suggest that androgen exposure during early life may masculinize personality characteristics relevant to social interaction, presumably via effects on neural development. Additionally, prenatal androgen influences may well interact with subsequent influences of socialization to shape personality traits.