Androgens modulate endometrial function.

Human endometrium is the major target tissue for sex steroid hormones. The circulating steroid hormones in normal ovulatory cycles accurately control the proliferation and differentiation of the endometrial cells. Androgens, such as testosterone and 5α-dihydrotestosterone, are a type of sex steroid hormones that mainly function in the differentiation, development, and maintenance of male sexual characteristics. Although androgens are best known for their role in male reproduction, the androgen receptor is present in both male and female reproductive organs and is essential for normal reproductive function. Recently, a series of evidence suggests that androgens contribute to endometrial physiology and pathologies. However, the roles of androgens in the endometrium remain insufficiently understood, with contradictory findings being reported. This review summarizes the studies that show the role of androgens in regulating the physiological conditions of the endometrium and the implantation process, and endometrial pathology including endometriosis and others.