For decades, sex assignment in children with intersex conditions has depended more on surgical possibilities than on other criteria, since it was assumed that children are psychosexually neutral at birth. Adults with intersex conditions and professionals in the field have increasingly criticized this policy after the publication of studies suggesting that prenatal brain exposure to sex hormones determines gender development. Although prenatal brain exposure to androgens plays some part in the development of gender role behaviour, the current evidence is not in line with the idea of determination of gender identity through prenatal sex steroid exposure. Recent reviews on gender dysphoria and gender change in patients with intersex conditions show that initial gender assignment still seems to be the best predictor of adult gender identity.