What is "mestranol"

n. The 3-methyl ether of ethinylestradiol; the estrogen used in many of the first oral contraceptives.

n. a synthetic form of estrogen used in combination with a progestin in oral contraceptives

Mestranol ( INN, USAN, BAN, JAN) (brand names Devocin, Ovastol, Tranel), also known as ethinyl estradiol methyl ether (EEME), is a synthetic, steroidal estrogen that has been widely used medically. It was employed as the estrogen component in many of the first oral contraceptives, such as mestranol/noretynodrel (brand names Enovid, Enavid), and is still in use today. It was also a component of Ortho-Novin, Femigen, and Norbiogest. In addition to its use as an oral contraceptive, mestranol has been used as a component of hormone replacement therapy.

Mestranol is the 3- methyl ether of ethinyl estradiol, and is a biologically inactive prodrug of ethinyl estradiol to which it is demethylated in the liver with a conversion efficiency of 70% (50 µg of mestranol is pharmacokinetically bioequivalent to 35 µg of ethinyl estradiol).