CGM-derived metrics can help identify GDM earlier than standard clinical risk indicators. Findings published in Diabetes Research and Clinical Practice demonstrate strong predictive performance of key glycemic metrics during the second trimester.

This prospective multi-ethnic cohort included 167 pregnant participants with at least 3 days of CGM use between 18 and 24 weeks’ gestation. All participants underwent 75-gram oral glucose tolerance testing at 24 to 28 weeks. Predictive performance was assessed using area-under-the-receiver-operating-characteristic-curve (AUROC) analyses with repeated cross-validation.

GDM developed in 18% of participants. The strongest predictive markers were %Time-above-7.8 mmol/L (%TA7.8) and the Hyper-Glycemic Risk Index (Hyper-GRI), each achieving AUROC values of 0.862. J-index, SD, and MAGE also exceeded AUROC 0.80, indicating high predictive strength. Accuracy was greater in individuals with body mass index (BMI) <23 kg/m² than in those with higher BMI. Incorporating CGM metrics into a model with maternal age, pre-pregnancy BMI, occupation, ethnicity, history of GDM, and family history improved predictive performance to a maximum AUROC of 0.895.

These results support the role of CGM for earlier identification of high-risk glycemic profiles, allowing more timely intervention to protect maternal and fetal outcomes.