Selection of steroid combinations for oral contraceptives of maximum benefit

Low-dose oral contraceptives differ in the specific progestin component. Our review of available animal and human data revealed differences between the progestins as to their potencies for estrogenic, anti-estrogenic, androgenic and progesterone effects. Ideally, oral contraceptive formulations should have the minimal effective dose, sufficient to prevent pregnancy but with the fewest metabolic changes. The risk of cardiovascular disease may be predicted by changes in the composition and amount of circulating lipoproteins. Progestins with significant androgenic potency can lower high-density lipoprotein2; that is a possible adverse effect. Randomized, blind, comparative trials of the new multiphasic preparations are needed to determine which ones truly cause the fewest metabolic changes that might be of clinical significance.