Return to Ovulatory Capacity With Three Combined Oral Contraceptive Regimens

Abstract

INTRODUCTION: This study was designed to evaluate the effect of the combined oral contraceptive regimen LeCette (150 micrograms desogestrel and 20 micrograms ethinyl estradiol for 21 days followed by 10 micrograms of ethinyl estradiol for 7 days) and two different 28-day combined oral contraceptives on ovulation inhibition and return to ovulatory capacity. METHODS: In this phase 1, randomized, open-label comparative study, healthy, nonsmoking women aged 18–35 years with regular menstrual cycles were randomized to receive one of three combined oral contraceptives for three consecutive 28-day cycles. The three combined oral contraceptives evaluated were 21 days desogestrel and ethinyl estradiol followed by 7 days of ethinyl estradiol (desogestrel and ethinyl estradiol+ethinyl estradiol); 24 days of 3 mg drospirenone and 20 micrograms ethinyl estradiol followed by 4 placebo days (drospirenone and ethinyl estradiol and placebo); and 21 days of 100 micrograms levonorgestrel and 20 micrograms ethinyl estradiol followed by 7 placebo days (levonorgestrel and ethinyl estradiol+placebo). The proportion of women who returned to ovulatory capacity after combined oral contraceptive discontinuation was a secondary endpoint. Ovulatory capacity was defined as serum progesterone concentrations of at least 15.9 nmol/L on posttreatment cycle days 18, 19, or 20. RESULTS: A total of 206 women were randomized, 146 were evaluated for safety, and 142 were evaluated for efficacy. Greater ovarian suppression and ovulation inhibition were observed with desogestrel and ethinyl estradiol+ethinyl estradiol and drospirenone and ethinyl estradiol+placebo compared with levonorgestrel and ethinyl estradiol+placebo during the study. Return to ovulatory capacity occurred in approximately 76% desogestrel and ethinyl estradiol+ethinyl estradiol, 75% drospirenone and ethinyl estradiol+placebo, and 58% levonorgestrel and ethinyl estradiol+placebo of women. Adverse events were comparable among groups and consistent with those observed with other combined oral contraceptives. CONCLUSION: Regimens with altered or eliminated hormone-free intervals provided greater ovarian suppression with little delay in return to ovulatory capacity.