The Prevalence of Insulin Resistance and Its Association With Thyroid-Stimulating Hormone and Obesity in Infertile Women With Different Polycystic Ovary Syndrome Phenotypes

The aim of this study was to investigate the prevalence of insulin resistance (IR) according to the phenotypic subgroups of polycystic ovary syndrome (PCOS) and to determine the associations of TSH levels and body mass index (BMI) with IR in infertile women with PCOS. In this cross-sectional study, we included 400 infertile women with a diagnosis of PCOS according to Rotterdam criteria who were referred to the infertility clinic of amir-al-Momenin University Hospital from April 2018- to January 2020. They were classified into four different phenotypic subgroups according to ESHRE guidelines. The homeostasis model (HOMA-IR) was used to measure IR. The prevalence of insulin resistance was 39.3% in infertile women with PCOS. Among women with PCOS, the commonest phenotype was type I (68%), with type II (18.2%), type III (8.8%), and type IV (5%), respectively. Furthermore, there was no significant difference in the prevalence of IR among different phenotypes of PCOS. Logistic regression analysis showed that the chance of insulin resistance was higher in overweight (OR: 1.76, 95% CI: 1.07, 2.88, P=0.024) and obese PCOS women (OR: 3.25, 95% CI: 1.86, 5.67, P<0.001) compared with those who were normal or underweight. Moreover, the chance of IR was higher in PCOS women with TSH ≥2.5 μIU/ml as compared with those who had TSH <2.5 μIU/ml (OR: 2.00, 95% CI: 1.18, 3.40, P<0.001). Insulin resistance is a prevalent disorder among infertile Iranian women with PCOS BMI, and serum levels of TSH ≥2.5 μIU/ml are independent predictors of IR.