Abstract

Objectives: Adverse neonatal outcomes and risk factors associated with an abnormal 50-gram glucose challenge test (GCT) in pregnant women without a diagnosis of gestational diabetes mellitus (GDM) are not well described. We sought to examine the prevalence and associated risk factors for adverse neonatal outcomes among such a cohort in southern Thailand. Methods: We retrospectively collected data from three community hospitals in southern Thailand on pregnant women who delivered between January 2018 and December 2020 with abnormal 50-g GCT and normal 100-g OGT between 24 and 28 weeks of gestation. Obstetric outcome parameters and associated risk factors were collected from review of 822 patients medical records. Risk variables associated with adverse outcomes were investigated using univariate and multivariate logistic regression analyses. Results: Of maternal outcomes, the results showed that cesarean delivery was highly prevalent (46%), followed by postpartum hemorrhage (4.9%), and shoulder dystocia (3.8%). The three most prevalent neonatal outcomes were large-for-gestational-age (LGA) infants (33.8%), neonatal hypoglycemia (33.2%), and respiratory distress syndrome (RDS) (32.7%). The results of logistic regression analysis indicated that significant risks for LGA were pre-pregnancy body mass index >25 kg/m² (adjusted odds ratio (AOR), 1.83; 95% confidence interval (CI), 1.30–2.56) and total weight gain greater than the recommendation (AOR, 1.54; 95% CI, 1.11–2.14); significant risks for neonatal hypoglycemia were advanced maternal age (AOR, 2.05; 95% CI, 1.17–3.60), operative delivery (AOR, 2.33; 95% CI, 1.37–3.34), and neonatal RDS (AOR, 1.84; 95% CI, 1.12–3.03). Significant risks for neonatal RDS were total weight gain more than recommended (AOR, 1.46; 95% CI, 1.05–2.04) and preterm birth (AOR, 1.89; 95% CI, 1.07–3.36). Conclusion: Closer surveillance is needed for pregnant women with an abnormal 50-g GCT but without a diagnosis of GDM, particularly those with identified risk factors, due to the higher risk of adverse neonatal outcomes including hypoglycemia, LGA, and RDS.