In the female '''alpha-fetoprotein''' binds to estradiol which has been secreted by the fetal ovary. This binding results in the complex being unable to cross the [[Blood_Brain_Barrier_-_Anatomy_%26_Physiology|blood brain barrier]]. This mechanism protects the female brain from the masculinising effects of estradiol and allows the development of a 'feminising' '''surge centre''' at the point of the rostral part of the [[Midbrain_-_Anatomy_%26_Physiology|mesencephalon]]. | In the female '''alpha-fetoprotein''' binds to estradiol which has been secreted by the fetal ovary. This binding results in the complex being unable to cross the [[Blood_Brain_Barrier_-_Anatomy_%26_Physiology|blood brain barrier]]. This mechanism protects the female brain from the masculinising effects of estradiol and allows the development of a 'feminising' '''surge centre''' at the point of the rostral part of the [[Midbrain_-_Anatomy_%26_Physiology|mesencephalon]]. |