"Progesterone (abbreviated as P4), also known as pregn-4-ene-3,20-dione, is an endogenous steroid and progestogen sex hormone involved in the menstrual cycle, pregnancy, and embryogenesis of humans and other species. It belongs to a group of steroid hormones called the progestogens, and is the major progestogen in the body."@en . . . "17026" . "5994" . "10.0"^^ . "DB00396" . . . "DA04" . "Pregn-4-ene-3,20-dione"@en . "57-83-0" . "4G7DS2Q64Y" . "G03" . .