Plasma oestradiol and progesterone estimation for the monitoring of induction of ovulation with clomiphene and chorionic gonadotrophin.

Two hundred and thirty-five courses of treatment with clomiphene and human chorionic gonadotrophin (HCG) were administered for the induction of ovulation in 75 infertile women (three with primary amenorrhoea, 45 with secondary amenorrhoea and 27 with oligomenorrhoea) of whom 61 had previously been unsuccessfully treated with clomiphene alone. The treatment was monitored by plasma oestradiol estimations on day 15 and day 22 in 103 cycles and by plasma progesterone estimations on day 22 in all 235 cycles. Injections of HCG were given on day 15 and 22. Twenty patients failed to respond to treatment (43 courses). The remaining 55 patients showed no response in 32 courses, deficient responses in 55 cycles and adequate responses in 105 cycles (plasma progesterone level exceeding 10 ng per ml on day 22). The mean values (+/- SD) of plasma oestradiol on day 15, reflecting follicular development, were: 73 +/- 30 pg per ml for cycles with no response; 255 +/- 182 for deficient cycles and 366 +/- 226 pg per ml for adequate cycles. There was a positive correlation (r = 0-57) between day 15 plasma oestradiol and day 22 plasma progesterone values. Increased clomiphene dosage resulted in higher plasma oestradiol and progesterone levels. Thirty-nine pregnancies occurred in 34 out of 55 patients capable of response (62 per cent). The plasma progesterone levels during conception cycles were higher than those in non-conception cycles in the same patients. Monitoring of induction of ovulation by plasma hormone estimations allows detection and correction of inadequate response.