GPT and gestational diabetes: Specifically, elevated ALT levels had a direct impact on neonatal birth weight (β = 0.0291, 95% CI: 0.0100–0.0635), while GDM had an indirect effect (β = 0.0025, 95% CI: 0.0012–0.0056), with GDM accounting for 8.1% of the mediation effect.