Early Predictors of Gestational Diabetes Mellitus in IVF-Conceived Pregnancies

Gestational diabetes mellitus (GDM) is associated with adverse maternal and fetal outcomes. This study aimed to identify early and reliable GDM predictors that would enable implementation of preventive and management measures.

The participants were a 28-week prospective cohort of in vitro fertilization (IVF)-conceived pregnant women (≤39 years, body mass index [BMI] 18.5-38 kg/m²) without a known history of diabetes mellitus. Fasting blood samples were analyzed at baseline (pre-IVF) and 12 weeks' gestation for reproductive hormones, glucose, serum insulin, lipids, thyroid function, adiponectin, and lipopolysaccharide-binding protein. At 28 weeks, a 75-g oral glucose tolerance test was used to screen for GDM.

For the overall group at baseline, 22% had BMI ≥30 kg/m², 45% had polycystic ovary syndrome, 16% had hemoglobin A1C of 5.7% to 6.1%, and 14% had a past history of GDM. At 28 weeks of gestation (n = 158), 34 women had developed GDM and 124 had not. Significant baseline predictors of GDM onset included greater BMI (29.0 vs 25.8 kg/m²), older age (34 vs 32 years), higher levels of follicle-stimulating hormone/luteinizing hormone ratio (1.2 vs 1.0), hemoglobin A1C (5.5 vs 5.2%), insulin (10.6 vs 7.1 μIU/mL), homeostatic model assessment of insulin resistance (2.2 vs 1.7), total cholesterol (199 vs 171 mg/dL), and low-density lipoprotein cholesterol (123 vs 105 mg/dL), and lower triglyceride levels (74 vs 76 mg/dL). Significant 12-week GDM predictors included greater maternal weight gain (delta: 3.4 vs 1.5 kg) and higher levels of insulin (11.3 vs 7.6 μIU/mL), triglycerides (178 vs 120 mg/dL), and homeostatic model assessment of insulin resistance (2.3 vs 1.5). Twelve-week BMI is a predictor of GDM following adjustment for polycystic ovary syndrome status and maternal age.

While preconception maternal BMI, age, and follicle-stimulating hormone/luteinizing hormone ratio are predictors of subsequent development of GDM, early IVF-conceived gestational weight gain is the best predictor of GDM onset.