Gonane progestins are more potent and, except for levonorgestrel, less androgenic than the estrane progestins that preceded them. The current, informal method for classifying oral contraceptives (OCs) as old, first generation, or second generation on the basis of their date of introduction obscures the fact that each of the gonane progestins has unique biologic properties. Recommended, instead, is the classification of OCs according to their level of androgenicity. Under such a system, norgestimate, desogestrel, and monophasic norethindrone (0.4-0.5 mg) would fall into the low category. Triphasic levonorgestrel, norethindrone (1.0 mg), norethindrone acetate (1.0 mg), and ethynodiol diacetate (1.0 mg) would be classified as having medium androgenicity, while norgestrel (0.3 mg), norethindrone acetate (1.5-2.5 mg), and levonorgestrel (0.15 mg) would fall into the high androgenicity category.
|Original language||English (US)|
|Number of pages||5|
|Issue number||3 SUPPL.|
|State||Published - Sep 1 1998|
ASJC Scopus subject areas
- Reproductive Medicine
- Obstetrics and Gynecology