Conflicting evidence for continuous glucose monitoring in gestational diabetes: current challenges and the imperative for individual participant data meta-analysis.

BACKGROUND

The incidence of gestational diabetes mellitus (GDM) is rising along with rates of obesity and type 2 diabetes. GDM is associated with an increased risk of various short- and long-term complications for both mother and child, including type 2 diabetes. Managing GDM requires a multidisciplinary approach that includes dietary guidance, promoting regular physical activity, and performing self-monitoring of blood glucose (SMBG). Continuous glucose monitoring (CGM) has transformed pregnancy care in women with type 1 diabetes and is increasingly being proposed as a strategy to improve glycaemic management in GDM. By capturing postprandial glucose excursions, glycaemic variability, and time in range, CGM provides a more detailed picture of glycaemia and has raised expectations of improved metabolic control and pregnancy outcomes.

MAIN BODY: Despite these theoretical advantages, evidence for CGM in GDM remains conflicting. More recently, several large randomized controlled trials (RCT's) show conflicting data: some studies show modest improvements in glycaemic measures, whereas others report no clear benefit for key maternal or neonatal outcomes, leaving the clinical value and cost-effectiveness of CGM unclear. A major limitation is the absence of validated CGM-based glycaemic targets specific to GDM, and current guidelines offer little direction beyond conventional SMBG guidelines. Future research should prioritize adequately powered large RCT's representing a broad population, and, importantly, individual participant data meta-analyses to reconcile inconsistent findings, identify subgroups most likely to benefit, establish pregnancy-specific CGM thresholds, and evaluate the impact on both obstetric outcomes and long-term postpartum metabolic risk.

CONCLUSIONS

This ongoing debate underscores the need to critically appraise the role of CGM in GDM, summarize results from completed RCT's and meta-analyses, recognize key methodological and clinical evidence gaps, and outline the steps required for CGM to become fully integrated into standard GDM care.