Acute Glucose Load, Inflammation, Oxidative Stress, Nonenzymatic Glycation, and Screening for Gestational Diabetes.

Aims: To investigate if oral glucose tolerance test (OGTT) associates with changes in maternal symptoms (ie, flushing, sweating), blood nonenzymatic advanced glycation end products (AGE), acute-phase reactive inflammatory markers, and oxidative stress.

Methods: Prospective case-control study of patients screened for gestational diabetes mellitus (GDM). One hundred nonfasting, second-trimester consecutive pregnant women allocated to either 50 g OGTT or water. Five women who had a 3-hour fasting 100 g OGTT also enrolled. Maternal serum glucose, AGE, soluble receptor for AGE (sRAGE), interleukin (IL)-6, and C-reactive protein (CRP) were immunoassayed. Total radical-trapping antioxidant parameter (TRAP) estimated with antioxidant capacityperoxyl assay. Data corrected for gestational age and maternal body mass index.

Results: During 50 g OGTT there was a decrease in systolic blood pressure not accompanied by the onset of adverse clinical symptoms. There was a decrease in serum glucose levels 1 hour after water (P = .019) but not glucose ingestion. Serum CRP (P = .001) but not IL-6 was increased. The AGE, sRAGE, and TRAP levels remained unchanged. Similar results were seen during 100 g OGTT, except serum glucose was significantly elevated after 1 hour.

Conclusion: Results suggest screening tools for gestational diabetes are safe and clinically well tolerated during pregnancy.

Clinical Trial Registration: ClinicalTrials.gov NCT03029546.