Return of ovulation after evacuation of hydatidiform moles

Plasma levels of progesterone, 17 beta-estradiol and prolactin and serum levels of the beta-subunit of human chorionic gonadotropin were measured by radioimmunoassay before evacuation and then weekly after evacuation in 52 patients with complete moles and 15 patients with partial moles. The first menstrual cycle was ovulatory in 20 patients (29.9%) and anovulatory in 36 patients (53.7%). In 11 patients (16.4%) it was uncertain whether they ovulated in the first cycle. There was no difference in the ovulation rate between patients with complete moles and those with partial moles. The ovulation rate in patients with theca-lutein cysts was lower than that in patients without theca-lutein cysts. The preevacuation serum level of the beta-subunit of human chorionic gonadotropin in patients who ovulated in the first cycle was significantly lower than that in patients who did not ovulate, but there was no significant difference in the other hormones. By the sixth week, 12 patients already had the first ovulatory menstrual period and 40% of patients ovulated when the serum level of the beta-subunit of human chorionic gonadotropin was still above 10 mlU/ml. It is recommended that an effective method of contraception be instituted immediately after evacuation of hydatidiform moles.