Glucometer Versus Standard Enzymatic Method for Gestational Diabetes Mellitus: A Systematic Review for Diagnostic Test Accuracy

BACKGROUND: Gestational diabetes mellitus (GDM) is a major obstetric complication associated with adverse maternal and neonatal outcomes. Although the oral glucose tolerance test (OGTT) remains the diagnostic gold standard, its implementation is often constrained by logistical, financial, and infrastructural limitations, particularly in low- and middle-income countries. Point-of-care (POC) glucometers offer a rapid and accessible alternative; however, their diagnostic accuracy in pregnant populations remains uncertain. METHODS: This systematic review followed the Joanna Briggs Institute (JBI) methodology for diagnostic test accuracy reviews. Electronic databases including PubMed, EMBASE, and the Cochrane Library, as well as gray literature sources, were searched for studies published from 2013 to March 2025. Eligible studies included pregnant women screened for GDM using POC glucometers compared with OGTT as the reference standard. Data on diagnostic performance and methodological quality were extracted and assessed using JBI and QUADAS-2 tools. Due to substantial heterogeneity, findings were synthesized narratively. RESULTS: Six studies comprising 2,856 pregnant women were included. Reported sensitivity ranged from 27.0% to 100%, while specificity ranged from 31.5% to 98.8%. Diagnostic performance varied widely depending on device type, enzymatic method, calibration of diagnostic thresholds, and pre-analytical handling. Studies employing validated enzymatic methods and calibrated capillary thresholds demonstrated higher accuracy, whereas unadjusted cut-offs and inconsistent procedures were associated with poor performance. CONCLUSION: POC glucometers may serve as alternative tools for GDM diagnosis in resource-constrained settings; however, their reliability is highly dependent on procedural rigor and threshold validation. Further standardized, high-quality studies are required before routine clinical adoption can be recommended.