Norgesterone

Norgesterone (INN), also known as norvinodrel, vinylestrenolone, or vinylnoretynodrel, as well as 17α-vinylestr-5(10)-en-17β-ol-3-one and 17α-vinyl-δ⁵⁽¹⁰⁾-19-nortestosterone, is a steroidal progestin of the 19-nortestosterone group that was first described in 1965. Combined with ethinylestradiol as Vestalin, it is (or has been) used as a hormonal contraceptive. Norgesterone is virtually devoid of androgenic activity in animal assays.