Circulating miR ‐342‐3p as a biomarker for diagnosing gestational diabetes mellitus and predicting adverse perinatal outcomes: A retrospective cohort study

AIMS: This study evaluated the clinical utility of circulating miR-342-3p for diagnosing gestational diabetes mellitus (GDM) and predicting adverse perinatal outcomes (APOs). METHODS: A retrospective cohort of 261 GDM women (the GDM group) and 261 propensity score-matched healthy controls (the Normal group) was analyzed. Circulating miR-342-3p levels were quantified by RT-qPCR, and diagnostic and predictive performances were assessed using receiver operating characteristic curves. Correlations with fasting plasma glucose (FPG), 2-h postprandial glucose (2hPG), and Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) were evaluated by Spearman's analysis. Logistic regression was used to analyze the independent association between circulating miR-342-3p expression and APOs. RESULTS: Circulating miR-342-3p was significantly elevated in GDM patients versus controls and demonstrated early diagnostic potential for GDM (AUC = 0.835). In GDM patients, miR-342-3p levels showed moderate positive correlations with FPG, 2hPG, and HOMA-IR (r = 0.780, 0.578, 0.613). miR-342-3p levels were elevated in both the GDM-APOs and the Normal-APOs groups compared with their respective non-APO subgroups. Circulating miR-342-3p yielded AUCs of 0.697 and 0.599 for predicting APOs in the GDM and Normal groups, respectively. After adjusting for pre-pregnancy BMI, parity, FPG, and 2hPG, the ORs for APOs per unit increase in miR-342-3p were 1.338 in the GDM group and 2.284 in the Normal group. CONCLUSION: Circulating miR-342-3p may serve as a valuable adjunctive biomarker for early GDM screening. Across both GDM and non-GDM populations, circulating miR-342-3p is significantly associated with APOs, suggesting cross-population applicability, though GDM status may modulate the strength of this association.