Gestational diabetes mellitus risk factors in women with polycystic ovary syndrome (PCOS).

Objectives: To compare the incidence of gestational diabetes mellitus (GDM) in Iranian infertile women with polycystic ovary syndrome (PCOS) and women without PCOS after pregnancies resulting from either assisted reproductive technology (ART) or spontaneous as well as to determine the risk factors of GDM in PCOS women.

Study Design: In a cross-sectional study, we evaluated medical records of 234 spontaneous pregnant women without PCOS in Akbarabadi Women's Hospital affiliated to Tehran University of Medical Science, Tehran, Iran, along with 234 pregnant women with PCOS and 234 pregnant non-PCOS women with ART conception who were treated at Royan institute, Tehran, Iran, at the same period of time, 2012 to February 2013. Exclusion criteria were as following: maternal age ≥40, family history of diabetes in first-degree relatives, pre-pregnancy diabetes and history of gestational diabetes, history of stillbirth, recurrent miscarriage, birth weight baby ≥4kg (macrosomia), parity >4, Cushing's syndrome, congenital adrenal hyperplasia and overt hypothyroidism. The GDM diagnosis was according to American Diabetes Association (ADA) criteria. Incidence and the risk factors for GDM were evaluated.

Results: The incidence rates of GDM were 44.4%, 29.9% and 7.3% for PCOS ART, non-PCOS ART and non-PCOS spontaneous pregnant women, respectively. Multivariable logistic regression was used for determining risk factors of GDM in PCOS women with adjusted odds ratios for age, parity and hypothyroidism, the results revealed the most important and significant predictors for development of GDM in PCOS women as follow: menstrual irregularity (OR=4.2; 95% CI=1.7-10.6), serum triglycerides level ≥150mg/dL (OR=1.9; 95% CI=1.07-3.6) and pregestational metformin use (OR=0.4; 95% CI=0.2-0.7).

Conclusions: Pregnant Iranian women with a history of infertility and PCOS are at increased risk for developing GDM. It is recommendable to perform screening test for GDM in PCOS women with ART treatment, irregular menses and high serum triglycerides level in the early stage of pregnancy. Pregestational use of metformin can be effective in reducing the occurrence of GDM.