In primates, the developmental influence of androgens is less clear, and the consequences are less understood. Within the brain, testosterone is aromatized (to estradiol), which is the principal active hormone for developmental influences. The human testis secretes high levels of testosterone from about week eight of fetal life until five to six months after birth (a similar perinatal surge in testosterone is observed in many species), a process that appears to underlie the male phenotype. Estrogen from the maternal circulation is relatively ineffective, partly because of the high circulating levels of steroid-binding proteins in pregnancy.
in primates the developmental influence of androgens is less clear and the consequences are less understood within the brain testosterone is aromatized (to estradiol) which is the principal active hormone for developmental influences the human testis secretes high levels of testosterone from about week eight of fetal life until five to six months after birth (a similar perinatal surge in testosterone is observed in many species) a process that appears to underlie the male phenotype estrogen from the maternal circulation is relatively ineffective partly because of the high circulating levels of steroid-binding proteins in pregnancy