PCOS/PMOS is a complicated syndrome, involving multiple feedback loops in the anterior pituitary, liver, pancreas, and ovary ultimately contributing to a hyperandrogenic state. In the pituitary, LH is released in higher quantities than FSH, simulating the theca cells of the ovary to increase production of androgens. The androgens in turn stimulate the pituitary to release LH and FSH. The increased androgen also acts on the liver, decreasing SHBG, which increases circulating free androgens. Finally, at the level of the pancreas, androgens lead to hyperinsulinemia, which in turn also decreases SHBG. Insulin also acts on the theca cells to promote androgen release. All of these factors lead to HA, which leads to anovulation and PCOM in the ovary. LH, luteinizing hormone; FSH, follicle-stimulating hormone; SHBG, sex hormone–binding globulin.