Gonadotropin and estradiol levels during ovarian stimulation in women treated with leuprolide acetate.

Levels of FSH, LH, and estradiol (E2) were measured in the serum of 209 gonadotropin-releasing hormone analogue-treated women and in 202 control subjects during the final 5 days of ovarian stimulation in our in vitro fertilization program. Levels of FSH and E2 in serum of gonadotropin-releasing hormone analogue-treated subjects significantly exceeded control values during the sampling period, whereas LH levels were significantly lower. Concentrations of E2 in serum of gonadotropin-releasing hormone analogue-treated and control subjects were similar when corrected for differences in numbers of follicles aspirated at oocyte retrieval (mean of 8.9 and 7.2 follicles per subject, respectively). Pregnancy rates by diagnostic ultrasound were 18 and 11%, respectively, a statistically significant difference.