What is "norgestrienone"

n. A steroidal progestin.

Norgestrienone ( INN) (brand name Ogyline, Planor), also known as 10,11-didehydro-orethisterone, as well as 17α-ethynyltrienolone (17α-ethynyl trenbolone), is a steroidal progestin that is used as a hormonal contraceptive, sometimes in combination with ethinyl estradiol. It is a relatively weak progestin, and has some androgenic effects. Norgestrienone was synthesized in the 1960s. Gestrinone is the ethyl derivative of norgestrienone.