Anti-Müllerian hormone plasma levels in spontaneous menstrual cycle and during treatment with FSH to induce ovulation

Background: Anti-Müllerian hormone (AMH) is member of the transforming growth factor-β superfamily of growth factors. AMH is detected in serum from women of reproductive age and its levels vary slightly with the menstrual cycle, reaching the peak value in the late follicular phase. The present study was undertaken to assess the effect of controlled ovarian stimulation on AMH secretion by the ovary in healthy women in order to obtain more insight into the relationship between this peptide and gonadal steroids. Methods: Twenty-four normally cycling women attending the infertility clinic volunteered for this study and AMH was measured in blood samples obtained during both spontaneous and FSH-treated cycles. Results: AMH plasma levels did not change significantly from day 2 to day 6 in spontaneous cycles. On the contrary, AMH levels decreased progressively from day 2 to day 6 in FSH-treated cycles. A significant positive correlation was found between the decrease in AMH and the increase in estradiol plasma levels in FSH-treated cycles and between basal AMH and the peak estradiol (E₂) during exogenous FSH administration. Conclusions: The present study demonstrated that AMH plasma levels did not change during the follicular phase of the menstrual cycle and that exogenous FSH administration is followed by a significant reduction in AMH levels which is probably secondary to the gonadotrophin effect on the process of follicular development.