Mullerian-Inhibiting Substance/Anti-Mullerian Hormone as a Predictor of Preterm Birth in Polycystic Ovary Syndrome

Context: There is increasing evidence for Mullerian-inhibiting substance (MIS)/anti-Mullerian hormone (AMH) physiologic activity in the human uterus, so it is relevant to study how MIS/AMH levels impact pregnancy. Objective: To investigate the association of MIS/AMH levels with the risk of adverse obstetric outcomes. Design: Retrospective cohort study. Setting: Academic fertility center. Patients: Women who became pregnant through in vitro fertilization between January 2012 and October 2016. Exclusion criteria were: oocyte donation, gestational carrier, multiple gestations, miscarriage before 20 weeks, or medically indicated preterm deliveries. Interventions: None. Main Outcome Measures: Therewere two primary outcomes, pretermbirth and cesarean delivery for arrest of labor. Because MIS/AMH level is highly skewed by certain infertility diagnoses, the preterm birth analysis was stratified by polycystic ovary syndrome (PCOS) diagnosis, and the cesarean delivery for arrest of labor analysis was stratified by diminished ovarian reserve diagnosis. chi(2), Mann-Whitney, and t tests were used as appropriate. A P value of <0.05 was considered statistically significant. Results: Among women with PCOS, those who delivered prematurely had substantially higher MIS/AMH levels (18 vs 6.4 ng/mL, P = 0.003) than did those who delivered at term. At the highest MIS/AMH values, preterm deliveries predominated; above the 90th percentile in women with PCOS, all deliveries were premature. No effect of MIS/AMH level was observed in women without PCOS. We found no association between MIS/AMH values and cesarean delivery for labor arrest. Conclusion: In women with PCOS, substantially elevated MIS/AMH levels are significantly associated with preterm birth, suggesting closer follow-up and further studies to elucidate the underlying mechanisms.