Fasting Plasma Glucose and Its Relationship to Anthropometric Phenotype in Women Diagnosed with Gestational Diabetes According to IADPSG Criteria

Background: Gestational diabetes mellitus (GDM) is characterized by new-onset hyperglycemia in pregnancy. According to the International Association of Diabetes and Pregnancy Study Groups (IADPSG) recommendations, GDM may be diagnosed based on repeatedly increased fasting glucose levels in the first trimester, or later, the detection of increased fasting glucose and/or increased glucose levels during a 75 g oral glucose tolerance test (OGTT). The study aimed to assess whether differences may be found between women diagnosed with GDM by fasting glucose or glucose challenge tests in early or late pregnancy. Methods: The retrospective observational study enrolled 418 women diagnosed with GDM in accordance with the IADPSG criteria: early pregnancy fasting plasma glucose (FPG) ≥ 5.1 mmol/L; late pregnancy FPG ≥ 5.1 mmol/L (0 min) and/or postprandial plasma glucose (PPG) ≥ 10.0 mmol/L (60 min), PPG ≥ 8.5 mmol/L (120 min) 75 g OGTT. The analyses included anthropometric parameters at the beginning and during pregnancy, laboratory values of glycated hemoglobin, fructosamine, birth weight measures and the presence of neonatal complications. Results: There were significant differences in body weight (78.3 ± 19.1; 74.0 ± 16.7; 67.2 ± 15.7 kg) and body mass index (BMI) (27.9 ± 6.6; 26.4 ± 5.8; 24.4 ± 5.2 kg/m2) in early pregnancy. Differences were also found in gestational weight gain (9.3 ± 6.8 vs. 12.4 ± 6.9 vs. 11.1 ± 4.7 kg) and the need for insulin therapy (14.7%; 7.1%; 4.0%). The study revealed no difference in the presence of neonatal complications but differences in birth weight (3372.2 ± 552.2 vs. 3415.6 ± 529.0 vs. 3199.0 ± 560.5 g). Conclusions: Gestational diabetes, characterized by FPG ≥ 5.1 mmol/L in early pregnancy, is associated with higher body weight and BMI at the beginning of pregnancy as well as with a higher risk for insulin therapy and increased birth weight