Efficacy, tolerability and acceptability of a novel contraceptive vaginal ring releasing etonogestrel and ethinyl oestradiol

Abstract

A novel contraceptive vaginal ring releasing etonogestrel 120 microg and ethinyl oestradiol 15 microg daily over a period of 3 weeks was tested. Each ring was used for one cycle, comprising 3 weeks of ring use followed by a 1 week ring-free period. This 1 year, multicentre study assessed the contraceptive efficacy, cycle control, tolerability and acceptability of the contraceptive. Altogether, 1145 women were exposed to the vaginal ring for 12,109 cycles (928 woman-years). Six pregnancies occurred during treatment, giving a Pearl Index of 0.65 (95% confidence interval 0.24--1.41). Cycle control was very good, since irregular bleeding was rare (2.6--6.4% of evaluable cycles) and withdrawal bleeding (mean duration 4.7--5.3 days) occurred in 97.9--99.4% of evaluable cycles. Compliance to the prescribed regimen was high with criteria being fulfilled in 90.8% of cycles. The ring was well tolerated. The majority of women considered this new contraceptive method easy to use, and it offers an effective, convenient, well-accepted and novel method for hormonal contraception.