Background: Polycystic ovary syndrome (PCOS) often induces reduced ovulation, infertility and hyperandrogenism. Many PCOS cases manifest different degrees of obesity. The increased body mass index (BMI) may interfere with a successful reproduction. The purpose of this study was to assess the effect of increasing BMI on anti-Mullerian hormone (AMH) gene expression in granulosa cells and also biochemical factors among PCOS cases.

Materials and Methods: This cross-sectional study was carried out on 80 patients (mean age 20-35 y with PCOS or other non-PCOS infertility disorders) referred to Tabriz-Alzahra Fertility Center.  Based on obesity degree and its signs, the cases were divided to four groups. In the same day of isolating oocytes, granulosa cells and serum were taken for gene expression   and the analysis of biochemistry factors, respectively.  

Results: AMH gene expression level were higher in PCOS compared to normal cases (P<0.05). While increasing BMI in the patients didn’t show a significant decrease of AMH gene expression (r=-0.07), a significant positive correlation was observed between AMH and insulin resistance (r= 0.34, P<0.05).

Conclusion: AMH gene expression in PCOS cases is affected by the disease phenotype. Insulin resistance plays an important role in increasing serum AMH.