Human Chorionic Gonadotropin

Human chorionic gonadotropin is a placental polypeptide hormone composed of α and β subunits. In the reviewed U.S. label, urinary-derived hCG products are FDA-approved for prepubertal cryptorchidism not due to anatomical obstruction, selected cases of male hypogonadotropic hypogonadism, and induction of ovulation and pregnancy in appropriately pretreated infertile women. The label explicitly states that hCG is not effective adjunctive therapy for obesity.

The reviewed label states that hCG action is virtually identical to pituitary LH, with a small degree of FSH activity. hCG binds the LH/CG receptor (LHCGR) and stimulates Leydig cells in the testis to produce androgens (testosterone) and the corpus luteum in the ovary to produce progesterone. The dual sex-steroid effect is the basis for both fertility uses and male androgen-stimulation uses. Diagnostic stimulation tests for testicular function also rely on the same Leydig-cell axis.