Are the changes in diagnostic criteria for gestational diabetes mellitus reflected in perinatal outcomes? A retrospective assessment

Background Gestational diabetes mellitus (GDM) is glucose intolerance first diagnosed during pregnancy not due to overt diabetes. Recent changes to the diagnostic guidelines have been shown to increase the apparent occurrence of GDM. Aim The aim of this study was to compare retrospectively the neonatal outcomes between groups defined using the new and old criteria to assess the impact of guideline changes on pregnancy outcomes. Methods The study was of singleton babies delivered of 641 women, who had oral glucose tolerance testing and pregnancy care at a single tertiary centre between 2011 and 2015. Results Compared to the population of women not now considered to have GDM by International Association of Diabetes and Pregnancy Study Groups criteria (two‐hour glucose concentration ≤8.4 mmol/L), neonates born to women with the new lower fasting criterion (5.1–5.4 mmol/L) and/or the new 60‐min group (glucose ≥10 mmol/L) combined were significantly more likely to have birthweight ≥90th percentile (22% vs 5%, P