Increase in serum leptin concentrations in women undergoing controlled ovarian hyperstimulation for assisted reproduction

The ob gene product might influence the hypothalamopituitary axis and ovarian function directly via specific ovarian receptors. Premenopausal women have higher leptin concentrations compared to postmenopausal controls. In this study, we determined changes in leptin serum concentrations under the influence of supraphysiological estradiol levels during controlled ovarian hyperstimulation In a prospective study of 20 patients undergoing in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI), morning blood samples were collected to determine leptin and estradiol concentrations on day 3 and day 9 of the stimulation cycle and on alternate days until ovulation induction. There was a significant increase in serum leptin concentrations from day 3 to clay 9 (9.87 +/- 1.5 ng/ml on day 3 and 13.8 +/- 2. 1 ng/ml on day 9 respectively). No further increase in leptin was observed until the day of ovulation induction. These data further underline the role of leptin as a hormone of reproduction.