Maternal and Neonatal Outcomes of Pregnant Women with Abnormal 50 g Glucose Challenge Tests in Nakhon Si Thammarat, Thailand: A Retrospective Study

(1) Background: An abnormal 50 g glucose challenge test (50 g GCT) during pregnancy, even without a diagnosis of gestational diabetes mellitus (GDM), may result in undesirable obstetric and neonatal outcomes. This study sought to evaluate the outcomes in pregnant women with abnormal 50 g GCT in secondary care hospitals in Thailand. (2) Methods: A total of 1129 cases of pregnant women with abnormal 50 g GCT results who delivered between January 2018 and December 2020 at Thasala, Sichon, and Thungsong hospitals were retrospectively reviewed and divided into three groups: abnormal 50 g GCT and normal 100 g oral OGTT (Group 1; n = 397 cases), abnormal 50 g GCT and one abnormal 100 g OGTT value (Group 2; n = 452 cases), and GDM (Group 3; n = 307 cases). (3) Results: Cesarean section rates in group 3 (61.9%) were statistically higher than those in groups 1 (43.6%) and 2 (49.4%) ( p < 0.001). In addition, the highest rate of birth asphyxia was found in group 2 (5.9%), which was significantly higher than that in Groups 1 (1.8%) and 3 (3.3%) ( p = 0.007). (4) Conclusions: Pregnant women with abnormal 50 g GCTs without a diagnosis of GDM had undesirable maternal and neonatal outcomes, as well as those who had GDM, suggesting that healthcare providers should closely monitor them throughout pregnancy and the postpartum period.