Simplified gestational diabetes screening with a triaging fasting plasma glucose reduces the burden of oral glucose tolerance tests during pregnancy - A large tertiary comparative cohort study

Aims: The study aimed to evaluate the impact of a simplified screening approach for gestational diabetes (GDM) compared to conventional screening on OGTT rates, GDM prevalence, and perinatal outcomes. Method: A retrospective comparative cohort study included singleton births from 20 weeks' gestation. Pregnancies without diagnostic glucose results from 13 weeks' gestation or incomplete screenings were excluded. Simplified screening consisted of a triaging fasting plasma glucose (FPG), where only those with FPG levels between 4.7 and 5.0 mmol/L proceeded to the 2hr 75 g oral glucose tolerance test (OGTT). The study period was divided into conventional screening (1st January 2019-30th June 2020) and simplified screening (1st January 2021-31st December 2021). Results: Out of 15,138 pregnancies, 12,035 met the inclusion criteria: 7385 underwent conventional and 4650 underwent simplified screening. In the simplified group, 82.9 % avoided an OGTT. The simplified screening group also had a lower GDM prevalence compared to the conventional group ((18.7 % vs. 21.7 %, p < 0.001). Perinatal outcomes, including the rate of large-for-gestational-age infants, were similar between the groups. Conclusion: The simplified GDM screening strategy for significantly reduced OGTTs by over 80% without impacting perinatal outcomes. It suggests that prospective studies are necessary to further evaluate this approach.