Trends in anti-Mullerian hormone concentrations across different stages of pregnancy in women with polycystic ovary syndrome

Research question: What are the trends in anti-Mullerian hormone (AMH) concentrations from pre-conception to the third trimester of pregnancy in women with polycystic ovary syndrome (PCOS)? Design: Observational study including cross-sectional and longitudinal data analysis. The Beckman Coulter AMH Gen II Assay was used to determine AMH levels longitudinally before pregnancy from 52 women with PCOS and 51 controls during all trimesters. Differences in AMH levels across successive stages of pregnancy were examined with the Wilcoxon signed-rank test for paired values. Linear regression models, adjusted for body-mass index (BMI), gestational and maternal age were used to compare AMH levels of PCOS and controls. Results: AMH levels decreased significantly (all P < 0.05) from pre-pregnancy level throughout each trimester in women with PCOS and healthy controls. After adjusting for maternal age, gestational age and maternal BMI, AMH levels before pregnancy were 1.89 (95% CI 1.46 to 2.44; P < 0.0001) times higher among women with PCOS compared with controls (median 766 versus 2.67 ng/ml). During the first trimester, AMH levels were 1.61 (95% CI 1.22 to 2.13; P = 0.001) times higher among women with PCOS compared with controls (median 5.33 versus 2.48 ng/ml). Differences in AMH levels between women with PCOS and controls in the second trimester (1.68 times higher; 95% CI 0.94 to 3.01; median: 5.50 versus 2.20 ng/ml) and the third trimester (1.45 times higher; 95% CI 1.01 to 2.07; median: 1.36 versus 1.06 ng/ml) were not statistically significant. Conclusion: These findings indicate a pregnancy-associated AMH-decline independent of pre-pregnancy elevated AMH levels.