Efficacy and safety of a low-dose 21-day combined oral contraceptive containing ethinylestradiol 20μg and drospirenone 3mg

Objective: The purpose of this study was to assess the efficacy and safety of a new low-dose oral contraceptive containing ethinylestradiol 20 mu g and drospirenone 3mg (EE 20 mu g/drsp 3mg). Methods: This was an open-label, non-comparative, multicentre study conducted at 33 centres in Germany and Switzerland. The combined contraceptive was administered over 26 cycles of treatment, with each cycle consisting of once-daily treatment for 21 consecutive days followed by a 7-day hormone-free interval. Results: A total of 527 women were randomised, of whom 516 (97.9%) started treatment and had at least one study observation. Two pregnancies occurred during 11 165 cycles of treatment, giving a Pearl Index of 0.23 (upper limit of 97.5% CI 0.84). The corresponding 2-year cumulative pregnancy rate was 0.44% (95% CIs 0, 1.05). One of the two pregnancies was attributed to non-compliance with treatment, giving an adjusted Pearl Index of 0.12 (upper limit of 97.5% CI 0.67) over 10 827 compliant cycles. Only three (0.6%) women discontinued treatment because of bleeding problems in this long-term study, suggesting an acceptable bleeding profile. Overall, the study drug was well tolerated and adverse events experienced were typical of hormonal contraceptive use. The majority of women who responded (435 of 501; 86.8%) were satisfied or very satisfied with the study treatment and most (367 of 501; 73.3%) would continue with it if given the choice. Conclusion: The EE 20 mu g/drsp 3 mg combined oral contraceptive is an effective and well tolerated contraceptive with an acceptable bleeding pattern.