Serum Periostin Levels as a Predictor of Gestational Diabetes Mellitus

Background: Gestational diabetes mellitus (GDM) is a common pregnancy complication associated with adverse maternal and neonatal outcomes. The identification of novel biomarkers for GDM remains an important clinical objective. The aim of this study was to investigate whether maternal serum periostin levels measured between 24 and 28 weeks of gestation could serve as a biomarker for the diagnosis of GDM and to evaluate their association with maternal and neonatal outcomes. Methods: This case-control study was conducted at Samsun Training and Research Hospital between January 2024 and February 2025. Serum periostin levels were measured by enzyme-linked immunosorbent assay (ELISA). Results: Serum periostin levels were significantly higher in the GDM group than in the control group (101.4 (53.6) vs. 34.6 (23.9) ng/mL, p < 0.001). Correlation analysis revealed that serum periostin levels were positively correlated with fasting glucose (r = 0.453, p < 0.001), 1-hour oral glucose tolerance test (OGTT) (r = 0.525, p < 0.001), 2-hour OGTT (r = 0.481, p < 0.001), maternal body mass index (BMI) (r = 0.750, p < 0.001), and fetal birth weight (r = 0.351, p < 0.001). Receiver operating characteristic (ROC) curve analysis demonstrated excellent diagnostic performance for serum periostin (area under the curve [AUC] = 0.932, 95% confidence interval [CI]: 0.899–0.966, p < 0.001). The multivariable model showed even higher diagnostic accuracy (AUC = 0.976, 95% CI: 0.957–0.994, p < 0.001). Conclusions: Maternal serum periostin levels are significantly associated with the presence of GDM and adverse perinatal outcomes. These findings suggest that periostin may represent a potentially useful biomarker associated with GDM; however, its role in screening or prediction requires further prospective validation.