Classic hypothalamic-pituitary-end-organ feed-back loops-the hypothalamic-pituitary-adrenal axis(HPAA),hypothalamic-pituitary-thyroidal axis (HPTA),and hypothalamic-pituitary-gonadal axis (HPGA)-are associated with the neuroendocrine and immune systems in major depressive disorder (MDD).Female patients with MDD present with evident neuroendocrine and immuno-logical changes.Glucocorticoid,thyroid hormone,and reproductive steroid levels fluctuate with menstrual cycles,which might lead to glucocorticoid receptor resistance,impairment of triiodothyronine conversion,and sex hor-mone secretion disorders.In this review,we summarize the independent and interactive functions of these three axes in female MDD patients.The similar molecular structure of steroids implies an interrelationship between the hypothalamic-pituitary-end-organ axes and the competitive inhibitory effects at the receptor level,especially when considering the HPAA and HPGA.