Inhibin activity of preovulatory follicles of gonadotropin-treated and untreated women.

In order to determine whether treatment of endocrinologically normal women with human menopausal gonadotropin (hMG) and human chorionic gonadotropin (hCG) led to alternations in follicular fluid inhibin activity and steroids, both inhibin activity and steroid levels were measured in follicular fluid of 10 follicles of 9 women treated with hMG/hCG and in follicular fluid of 15 preovulatory follicles of 15 untreated women. The women were given 150 IU hMG daily from day 3 until the serum estrogen levels were greater than 300 pg/ml, at which time hMG was discontinued and 10,000 IU hCG was given 50 hours later. Follicular fluid was aspirated from all visible follicles 36 hours after hCG. Women treated with hMG/hCG had multiple (two to five) follicles containing 1.5 to 4.5 ml of follicular fluid and a mature oocyte and elevated serum estrogen (400 to 800 pg/ml) on the day after hCG treatment. At the time of follicular fluid recovery, there was more inhibin activity (204 +/- 14 U/10 ml) in the hMG/hCG-stimulated follicles than in unstimulated follicles of a control group of women (65 +/- 14, mean +/- standard error, P less than 0.05). Follicular fluid from follicles of hMG/hCG-treated women had lower estrogen and progesterone levels, compared with normal preovulatory women. These data show that treatment of patients with hMG/hCG is associated with elevated follicular fluid inhibin activity.