Whenever a woman experiences shifts in sex hormones—as happens in puberty, with the monthly menstrual cycle, during pregnancy, during postpartum, and before and after menopause—there are changes in neurotransmitters (which influence mood) and neurosteroids. Neurosteroids affect how neurons fire in the brain, and they’re thought to play a role in the development of major depression, post-traumatic stress disorder, premenstrual dysphoric disorder (PMDD), and postpartum depression.
