The role of continuous glucose monitoring (CGM) in pregnancy remains under evaluation due to variability across prior studies. A systematic review and meta-analysis published in Diabetes, Obesity and Metabolism assessed randomized controlled trials (RCTs) comparing CGM with self-monitoring of blood glucose (SMBG) in pregnant women with gestational diabetes mellitus (GDM) and pregestational diabetes.

Electronic databases were searched to identify RCTs evaluating different CGM modalities, including real-time, flash, and retrospective systems. Diabetes subtypes and CGM modalities were analyzed separately. Primary outcomes included neonatal intensive-care unit (NICU) admission and large-for-gestational-age (LGA) infants, while secondary outcomes included additional neonatal and maternal outcomes along with glycemic metrics.

Seventeen RCTs were included, comprising 13 studies in GDM and 4 in pregestational diabetes. In GDM, real-time CGM showed lower NICU admission rates compared with SMBG (OR 0.55; 95% CI 0.34-0.90; p=0.02; I²=0%). Trial sequential analysis indicated limited information size despite evidence of effect. Retrospective CGM in GDM showed a lower risk of LGA (OR 0.46; 95% CI 0.22-0.98; p=0.048; I²=0%). Other maternal and neonatal outcomes, including birthweight, macrosomia, cesarean delivery, hypertensive disorders, neonatal hypoglycemia, and preterm birth, showed no significant differences. No measurable benefit was observed for any CGM modality in pregestational diabetes.

Real-time CGM demonstrated reductions in NICU admissions in GDM, while most other outcomes remained similar across monitoring strategies. Current evidence remains limited by information size, supporting the need for further RCTs.