Ovulation inhibition with a combined oral contraceptive containing 1 mg micronized 17β-estradiol

Abstract

To evaluate ovarian function by ultrasonography and endocrine measurements. Prospective, open study. Outpatient clinic of the First Department of Gynaecology and Obstetrics, University of Vienna, Austria. Twenty healthy women with regular cycles and established ovulation by ultrasonography. Treatment with a combination of 1 mg micronized E2 with 150 micrograms desogestrel daily for 21 days, followed by 7 pill-free days. Transvaginal ultrasonography and estimation of E2 and P at least twice a week for two consecutive cycles, followed by one after treatment cycle. Ovulation inhibition was apparent in all cases and no functional ovarian cysts were observed during treatment. On a few occasions a persistent follicle was noted, but in the majority of cases there was total absence of follicular activity. The bleeding pattern showed a tendency toward prolonged and more heavy bleeding when compared with the before treatment situation. Return of ovulation was prompt in all women but one. Ultrasonographic observations, accompanied by P and E2 measurements, allow us to conclude that the combination of 1 mg E2 with 150 micrograms desogestrel provides complete ovulation inhibition. However, the bleeding pattern does not show an acceptable profile.