Early-onset GDM linked to adverse pregnancy outcomes

Gestational diabetes mellitus (GDM) diagnosed early by oral glucose tolerance test (OGTT) at 18 to 20 gestational weeks predicts maternal and neonatal metabolic disorders as well as pregnancy outcomes, a study has found.

In this prospective cohort study, each of the 522 participants underwent two OGTTs: an early OGTT at 18 to 20 gestational weeks and a standard OGTT at 24 to 28 gestational weeks. The authors analysed the reproducibility between early and standard OGTT. They also compared the maternal and neonatal metabolic disorders and pregnancy outcomes across groups.

All participants completed both the early and standard OGTTs. Glucose values in the early OGTT were not significantly different from those in the standard OGTT (fasting: 4.31±0.41 vs 4.29±0.37 mmol/L; p=0.360; 1-hour: 7.68±1.71 vs 7.66±1.59 mmol/L; p=0.826; 2-hour: 6.69±1.47 vs 6.71±1.39 mmol/L; p=0.800). Early and standard OGTT results had a reproducibility of 74.9 percent.

Glycated haemoglobin, C-peptide, and homeostasis model assessment of insulin resistance in the late gestational period were higher among pregnant women in the GDM group. Neonates born to these mothers were also at greater risk of being large for gestational age (odds ratio [OR], 3.665, 95 percent confidence interval [CI], 1.006–11.91) and more prone to neonatal hyperinsulinaemia (OR, 3.652, 95 percent CI, 1.152–10.533).

“Further randomized controlled trials on the therapeutic efficacy for early-onset GDM will confirm the significance of early screening for GDM.