Mestranol/norethisterone
Mestranol/norethisterone (brand names Norethin, Noriday, Norinyl, Norquen, Ortho-Novum, others) is a combination of the estrogen estranol and the progestin norethisterone (norethindrone) which was introduced in 1963 and was the second combined oral contraceptive to be marketed, following mestranol/noretynodrel in 1960. Although most mestranol-containing oral contraceptive formulations have been discontinued, the combination remains available today in the United States in a single formulation under the brand name Norinyl 1+50 28-Day.