Attempts to programme ovulation with exogenous oestrogens and LH-RH analogue.

An attempt was made to programme ovulation in women on a predetermined day of the menstrual cycle by treatment used to induce ovulation in anovulatory sterility. At laparotomy for elective sterilization the ovaries were observed to assess the occurrence of ruptured follicles and ovulation. Histological analysis of ovaries and endometrium was performed, and ova were recovered from some women. Several regimens were tested but ovulation seldom occurred as planned. Clomiphene citrate, human chorionic gonadotrophin (HCG), synthetic luteinizing hormone releasing hormone (LH-RH), and ethinyloestradiol were ineffective. Human menopausal gonadotrophin followed by HCG was more effective, but multiple ovulations occurred. When one single injection of a potent long-acting LH-RH analogue was given on day 13 of the cycle to 10 women pretreated with ethinyloestradiol signs of recent ovulation were observed on day 15 in seven and on day 16 in two.