Effects of estradiol and FSH on leptin levels in women with pituitary suppression

Purpose: to identify the relationship between serum levels of leptin and the levels of estradiol and follicle-stimulating hormone (FSH) in women with pituitary suppression and to evaluate its possible interference on the reproductive axis. Methods: a total of 64 patients submitted to controlled ovarian hyperstimulation with recombinant FSH for assisted reproduction, due to a male or tubal factor, and 20 patients using estradiol valerate, for endometrial preparation in order to be submitted to oocyte donation treatment were studied. All patients used GnRH analogues before starting treatment in order to avoid premature LH surge. Data were analyzed statistically by the chi(2) test, Student's t-test and the Pearson correlation test, when appropriate, with the level of significance set at p<0,05. Results: it was observed that leptin levels correlated with body mass index (BMI) even though they had not influenced growth rate of these hormones. A positive correlation was observed between estradiol and leptin levels in both groups, as leptin levels increased from 10.42 to 15.68 ng/mL in the FSH group and from 11.09 to 14.5 ng/mL in the estradiol group, following estradiol increase. The growth rate of leptin was higher in women with higher estradiol levels, i.e., who had induced cycles with recombinant FSH, than in those who received estradiol valerate (159.60 +/- 58.01 and 136.73 +/- 34.17, respectively). Conclusion: we may state that leptin correlated with BMI and that both FSH and estradiol do interfere in the regulation of leptin production in women.