Serum 17beta-estradiol. Index of follicular maturation during gonadotropin therapy.

Thirteen patients with hypogonadotropic hypogonadism were treated with human menopausal gonadotropins (hMG) and human chorionic gonadotropin (hCG) to induce ovulation. Daily serum 17beta-estradiol (E2) assays were used to monitor the ovarian response to HMG. Apparent ovulation, documented by basal body temperatures, occurred in 41 of 53 hMG-hCG treatment cycles. Thirteen pregnancies occurred in 8 of the 13 patients. One twin pregnancy resulted. The hyperstimulation syndrome did not occur. Our data indicate that an optimal pregnancy rate with a minimum risk of hyperstimulation can be achieved when ovulation is induced 24 hours after the preovulatory serum E2 concentration has reached 500 to 900 pg/ml. Ovulation is induced by administering 10,000 IU and 5000 IU hCG on successive days. In addition, we now routinely give two or three injections of 2500 IU hCG at subsequent 3- to 4-day intervals to support the corpus luteum.