17α-Hydroxyprogesterone (17α-OHP), or hydroxyprogesterone (OHP), also known as 17α-hydroxypregn-4-ene-3, 20-dione is used under the brand name Gestageno, and has been marketed for clinical use in Argentina. It was indicated for female infertility, hypertrichosis, menstrual disorders, premature labour, threatened or recurrent miscarriage. It is used to properly regulate the menstrual cycle and treat unusual stopping of the menstrual periods (amenorrhea). To help a pregnancy occur during egg donor or infertility procedures in women who do not produce enough progesterone. To prevent estrogen from thickening the lining of the uterus (endometrial hyperplasia) in women around menopause who are being treated with estrogen for ovarian hormone therapy (OHT). To treat a condition called endometriosis, to help prevent endometrial hyperplasia, or to treat unusual and heavy bleeding of the uterus (dysfunctional uterine bleeding) by starting or stopping the menstrual cycle. 17α-OHP is an agonist of the progesterone receptor (PR) similarly to progesterone. In addition, it is an antagonist of the mineralocorticoid receptor (MR) as well as a partial agonist of the glucocorticoid receptor (GR), albeit with very low potency (EC50 >100-fold less relative to cortisol) at the latter site, also similarly to progesterone.