Progesterone

Progesterone is a C21-steroid hormone in which a pregnane skeleton carries oxo substituents at positions 3 and 20 and is unsaturated at C(4)-C(5). As a hormone, it is involved in the female menstrual cycle, pregnancy and embryogenesis of humans and other species. It has a role as a contraceptive drug, a progestin, a progesterone receptor agonist, a human metabolite and a mouse metabolite. It is a 20-oxo steroid, a 3-oxo-Delta(4) steroid and a C21-steroid hormone. It derives from a hydride of a pregnane.