Research Area: Cancer Biological Activity: Medroxyprogesterone acetate is a progestin, a synthetic variant of the human hormone progesterone and a potent progesterone receptor agonist. Medroxyprogesterone acetate is used as a contraceptive, in hormone replacement therapy and for the treatment of endometriosis as well as several other indications. Medroxyprogesterone acetate is a more potent derivative of its parent alcohol medroxyprogesterone. While medroxyprogesterone is sometimes used as a synonym for medroxyprogesterone acetate ), what is normally being administered is medroxyprogesterone 17-acetate and not medroxyprogesterone. Medroxyprogesterone acetate has approximately 100 fold higher binding affinity and transactivation potency compared to medroxyprogesterone. [1][2]