Objective:

To evaluate the potential of continuous glucose monitoring (CGM) for diagnosing gestational diabetes mellitus (GDM) and its association with specific pregnancy outcomes such as maternal and neonatal health.

Key Findings:

• CGM metrics differentiated patients who developed GDM from those who did not, with statistical significance.
• Higher mean glucose levels and greater glucose variability were observed as early as 13 to 14 weeks’ gestation in patients later diagnosed with GDM.
• CGM-derived glucose patterns were linked to adverse neonatal outcomes, including large-for-gestational-age infants and neonatal hypoglycemia.
• Some studies indicated CGM-detected glucose excursions correlated better with birth weight centiles than standard OGTT testing.
• Randomized trials showed mixed results regarding CGM's impact on clinical outcomes, with some showing benefits and others not.

Interpretation:

While CGM shows promise in identifying GDM and correlating with adverse outcomes, it has not been validated as a replacement for OGTT due to differences in measurement and the urgent need for standardized diagnostic thresholds.

Limitations:

• Reliance on observational data for diagnostic performance, which may not be generalizable.
• Heterogeneity in study design and CGM devices, including variations in technology and methodology.
• Lack of outcome-based diagnostic thresholds, which complicates clinical application.
• Many randomized trials were not powered to detect differences in clinical outcomes, limiting the strength of the findings.

Conclusion:

CGM may complement existing screening strategies but requires further validation in randomized controlled trials before being used diagnostically. Current evidence is insufficient to support CGM as a standalone diagnostic test for GDM, highlighting the need for more robust studies.