Anti-Mullerian hormone dynamics during controlled ovarian hyperstimulation and optimal timing of measurement for outcome prediction.

BACKGROUND Anti-Müllerian hormone (AMH) has been suggested as a marker of ovarian reserve and predictor of ovarian response to controlled ovarian hyperstimulation (COH). Several studies have demonstrated AMH changes during follicular and luteal phases during COH, but not after human chorionic gonadotrophin (hCG) administration. The objectives of this study were to investigate changes in AMH levels during the entire COH cycle and to clarify the regulatory mechanism of AMH secretion. In addition, we analyzed the COH outcome parameters to determine the optimal timing for AMH measurement to predict outcome. METHODS The study included 74 women who underwent in vitro fertilization (IVF) cycles with a GnRH agonist or antagonist protocol. Serum AMH and inhibin B levels were measured at baseline, Day 5 of stimulation (d5), day of hCG administration (dhCG), day of oocyte retrieval (dOPU) and 14 days after oocyte retrieval (dPO14). Follicular fluid (FF) from dominant follicles upon oocyte retrieval were also analyzed for AMH and inhibin B concentrations. AMH levels were analyzed for changes during the cycle and for correlations with COH outcome parameters. RESULTS Serum AMH levels decreased progressively during COH until dhCG, then increased on dOPU and further increased on dPO14. Serum and FF AMH levels and dynamic changes were not different between the GnRH agonist and antagonist cycles. Serum AMH levels on every sample day and the FF AMH levels were significantly correlated with outcomes of COH, such as dose of gonadotrophins used, estradiol level on dhCG and number of retrieved oocytes; the strength of the relationship was highest for baseline AMH. CONCLUSIONS The results of the present study suggest that changes in the hormonal milieu during stimulation and after the LH surge may affect AMH secretion. Serum AMH levels during COH are good markers to predict ovarian response, but the baseline serum level seems to be the most predictive marker.