A hormone made by the ovaries in females and the testicles in males. AMH helps to form the male and female reproductive organs. It also helps control other hormones that act on the ovaries to make the follicles and eggs grow during a woman’s menstrual cycle. Measuring the amount of AMH in the blood may help diagnose infertility and other conditions, such as polycystic ovarian syndrome, menopause, and certain types of ovarian tumors. It may also help determine the sex of an infant, when the sex is not clear. Also called anti-Mullerian hormone.