Efficacy and safety of a low-dose monophasic combination oral contraceptive containing 100 mu g levonorgestrel and 20 mu g ethinyl estradiol (Alesse (R))

The efficacy and safety of a low-dose 21-day combination oral contraceptive containing 100 mu g levonorgestrel and 20 mu g ethinyl estradiol were eval uated in an open-label, multicenter trial. A total of 1708 subjects with re gular menstrual cycles (27,011 cycles) were evaluated. The oral contracepti ve was administered once a day for 21 days, followed by 7 days of placebo f or a complete cycle. During 26,554 cycles evaluated for efficacy, 18 pregna ncies occurred (Pearl index of 0.88); 6 of these events were attributable t o subject noncompliance. After 30 cycles of exposure the cumulative rate of withdrawal as a result of accidental pregnancy was 1.9%. Breakthrough blee ding (with or without spotting) occurred in 12.9% of the cycles and spottin g alone occurred in 10.1% of the cycles. The 2 most common adverse events c ited as reasons for discontinuation were headache (2% of subjects) and metr orrhagia (2%). One serious event led to withdrawal of a subject. Overall, t he results of this study demonstrate that the monophasic regimen of 100 mu g levonorgestrel and 20 mu g ethinyl estradiol offers effective contracepti on, acceptable cycle control, and a good tolerability profile.