BOSTON – A prospective cohort study of women with polycystic ovarian syndrome who developed gestational diabetes mellitus during pregnancy has implicated fasting blood glucose, non–high density lipoprotein, and sex hormone–binding globulin as significant predictive factors for the development of GDM.
“Polycystic ovarian syndrome [PCOS] is the most common reproductive disorder in women of reproductive age and is commonly associated with metabolic disorders including diabetes and obesity. In women with GDM, a history of PCOS is associated with higher incidence of complications and postpregnancy glucose intolerance. Risk factors during early pregnancy in women with PCOS for development of GDM have not been well characterized,” said Dr. Wenyu Huang of Northwestern University, Chicago.
To provide some clarity, Dr. Huang and his colleagues conducted a prospective cohort study. Inclusion criteria were age 18-45 years, diagnosis of PCOS prior to conception, singlet pregnancy, and enrollment during the first trimester. Preexisting chronic disease including diabetes, hypertension, and thyroid, kidney, or cardiovascular disease was grounds for exclusion. The findings were presented at the annual meeting of the Endocrine Society.
The 248 women with PCOS enrolled from 2011 to 2013 from a screened population of 25,000 pregnant women were followed from their first prenatal visit (before week 18) to delivery. Blood was collected at the first visit for analysis of metabolic hormones. A 75-g oral glucose tolerance test (OGTT) was carried out at week 24-28 and diagnosis of GDM was according to 2013 American Diabetes Association OGTT criteria.
Of the 248 women, 75 (30.2%) developed GDM, and 173 (69.8%) women had normal OGTT results. Examination over the same time period early in pregnancy revealed a higher incidence of GDM in women with PCOS.
In a univariate analysis, PCOS patients who developed GDM had higher fasting blood glucose (FBG), Homeostasis Model Assessment-Insulin resistance (HOMA-IR) score, total cholesterol, low-density lipoprotein cholesterol, non-HDL cholesterol, systolic and diastolic blood pressures, and free testosterone index. These patients also had lower levels of sex hormone–binding globulin (SHBG) and higher likelihood of family history of diabetes and earlier delivery.
Multiple logistic regression revealed associations between increased incidence of GDM and FBG greater than or equal to 4.86 mmol/L, non-HDL cholesterol greater than or equal to 2.84 mmol/L, and SHBG greater than or equal to 222 nmol/L. The predictive power of the three factors for the development of GDM in PCOS was relatively strong.
Future studies could aim to validate the prediction model and clarify the pathogenic basis of GDM in PCOS women, according to the researchers .
The study was funded by the Beijing Science Committee. Dr. Huang had no disclosures.