Psychosexual development: an examination of the role of prenatal hormones.

Naturally occurring endocrine syndromes and the offspring from steroid-treated pregnancies are the major sources of evidence for a role of prenatal hormones in psychosexual development in man. Effects of prenatal androgens have been established for the sex-dimorphic behaviour clusters of energy expenditure (increased), parenting rehearsal (decreased), peer associations (shifted to male), and grooming-related behaviour (decreased); most of the information was obtained on the syndrome of congenital adrenal hyperplasia and in progestin-induced female hermaphroditism. Studies of children and adults exposed prenatally to exogenous oestrogens and/or progestagens suggest slight demasculinizing effects but cannot yet be considered conclusive. Gender identity is largely dependent on the sex of rearing; a direct role of prenatal hormones in its formation has not been shown. The evidence for the role of prenatal hormones in the development of sexual orientation is inconclusive.