Ultrasound evaluation of ovarian activity under oral contraceptives.

The trend towards changing the composition of the contraceptive pill in order to decrease side effects might lead to increased ovarian activity. This may decrease reliability. Therefore, a non-invasive method for monitoring the suppressive effect of the pill on ovarian function is warranted. The aim of the present study was to investigate whether or not diagnostic ultrasound might be the method of choice for studying residual ovarian activity during pill use. In 89 women on a low-dose oral contraceptive (30 mcg ethinyl-estradiol (EE)/75 mcg gestodene), the first two months of pill-intake were monitored extensively with diagnostic ultrasound. The study revealed that only one ultrasound investigation was needed during the first week of pill intake to discover all relevant cases of residual ovarian activity. Follow-up investigations are needed to quantify this activity more specifically.