Suppression of ovarian activity with a low-dose 21/7-day regimen oral contraceptive containing ethinylestradiol 20 mcg/drospirenone 3 mg in Japanese and Caucasian women

BackgroundTwo studies assessed the effect of a low-estrogen-dose 21/7-day oral contraceptive containing ethinylestradiol and drospirenone (EE 20 mcg/drsp 3 mg) on ovarian activity in Japanese and Caucasian women.Study DesignStudy 1 was conducted in Japanese women (20–35 years), and Study 2 was conducted in Caucasian women (18–35 years). All women received EE 20 mcg/drsp 3 mg in a 21-day active pill regimen. The primary endpoint was the proportion of women with ovulation inhibition (Hoogland score <6; as assessed by transvaginal ultrasonography) during treatment cycle 2.ResultsJapanese (n=23) and Caucasian (n=30) women received two cycles of study treatment. During treatment cycle 2, ovulation was inhibited in 100% and 92.9% of Japanese and Caucasian women, respectively.ConclusionsEE 20 mcg/drsp 3 mg in a 21/7-day regimen provides comparable ovarian suppression in Japanese and Caucasian women, with normal ovarian function resuming shortly after treatment end in both populations.