The Utility of Glycated Hemoglobin, Determined in the Second Trimester of Pregnancy, in Diagnosing Gestational Diabetes

Abstract

Abstract Background and Aims: Gestational diabetes (GD) identifies a pregnancy with high obstetrical risk due to the possible complications that may appear and which are associated with significant perinatal mortality and morbidity. The role of HbA1c in diagnosing GD is still debatable. Our aim was to evaluate the clinical utility of HbA1c assessed in the second trimester of pregnancy (before performing the oral glucose tolerance test - OGTT) in establishing the macrosomia risk, and also for diagnosing GD. Material and methods: This was an observational study on a group of 165 pregnant women followed from the first trimester of pregnancy in whom we measured HbA1c in the second trimester, before running an OGTT with 100 grams of glucose and who delivered at term (37 - 41 weeks of pregnancy). Finally, HbA1c and OGTT were performed only in 132 women, these being the subjects of our study. Results: The average value of HbA1c was 4.85±1.23%. HbA1c was higher in the group having gestational diabetes (6.58±0.74%) in comparison to the group not having GD (4.52±0,80%). The Receiver Operating Characteristic (ROC) curve for HbA1c determined in the second trimester, for diagnosis of GD, has an area under the curve (AUC) of 0.939. Conclusions: HbA1c value could be considered as a sensitive and specific predictive factor in appreciating the macrosomia risk and could be set as an extra criterion in GD diagnosis.