What is medroxyprogesterone? Medroxyprogesterone is a progestin (a form of progesterone), a female hormone that helps regulate ovulation (the release of an egg from an ovary) and menstrual periods. Medroxyprogesterone is used to treat conditions such as absent or irregular menstrual periods, or abnormal uterine bleeding. Medroxyprogesterone is also used to decrease the risk of endometrial hyperplasia (a condition that may lead to uterine cancer) while taking estrogens. Medroxyprogesterone is also used to prevent overgrowth in the lining of the uterus in postmenopausal women who are receiving estrogen hormone replacement therapy.