GPT and gestational diabetes: The ZJU index exhibited superior predictive ability for GDM, with an area under the curve (AUC) of 0.802 (95% CI: 0.72–0.88), significantly outperforming single biomarkers: TG (AUC = 0.781, 95% CI: 0.70–0.86), FPG (AUC = 0.659, 95% CI: 0.56–0.76), ALT/AST (AUC = 0.648, 95% CI: 0.55–0.75), and HDL (AUC = 0.603, 95% CI: 0.50–0.71).