Premenstrual Dysphoric Disorder and Postpartum Major Depression: Chronobiology

Investigators have proposed many theories for the pathogenesis of premenstrual and postpartum depression. Evidence for chronobiological theories shows that disturbances in the timing (phase) or amplitude of circadian rhythms contribute to the symptoms manifested in these disorders related to women's reproductive cycle. Relevant circadian rhythms include sleep, melatonin, cortisol, thyroid hormones, and prolactin (PRL). Diurnal patterns of secretion of these hormones in relation to sleep and to the changing reproductive hormones of each epoch are described. Disturbances in melatonin and PRL characterize premenstrual depressive disorders, whereas disturbances in sleep are common in postpartum depressive disorders.