Efficacy, cycle control, and side effects of low- and lower-dose oral contraceptives:: A randomized trial of 20 μg and 35 μg estrogen preparations

Estrogen content represents a tradeoff between cycle control and side effects, but few direct comparisons of 20 and 30/35 mu g preparations are available. To address this issue, we conducted a randomized, open-label multicenter clinical trial comparing Alesse(R) (20 mu g ethinyl estradiol [EE]), Mircette(R) (20 mu g EE), and Ortho Tri-Cyclen(R) (35 mu g EE) among 463 OC starters or switchers. Bloating, breast tenderness, and nausea were approximately 50% more common in women using 35 mu g EE as compared to 20 mu g EE preparations. Cycle control was similar in all products, although during the first two cycles among starters; users of Mircette and Ortho Tri-Cyclen (Tri-Cyclen) exhibited better cycle control than Alesse users. Discontinuation and pregnancy rates were not significantly higher in 35 mu g EE users. CONTRACEPTION 2000; 60:321-329 (C) 2000 Elsevier Science Inc. All rights reserved.