Liver enzymes as predictors of gestational diabetes: a meta-analysis

Gestational diabetes mellitus (GDM) is a metabolic disorder of pregnant women that develops during their second or third trimester. As an important organ in carbohydrate and lipid metabolism, the liver may play a role in GDM pathophysiology. This meta-analysis examined the conflicting relationship between liver enzyme levels and GDM risk while emphasizing the probable use of liver enzymes as a biomarker for early detection and prevention of GDM.

Literature from PubMed, EBSCO, Google Scholar, and ScienceDirect was systematically reviewed through August 2025. A total of seven studies were included after meeting the inclusion criteria. The pooled data were converted to mean and SD, then analyzed with the random-effects model to estimate ORs with 95% CIs. ROC curves were generated to determine the AUC and evaluate the diagnostic performance of liver enzymes. Subgroup analyses were made based on ethnicity and timing of the enzyme test.

ALT (SMD = 1.11; 95% CI: 0.72–1.49; p < 0.00001) and GGT (SMD = 0.79; 95% CI: 0.48–1.09; p < 0.00001) levels were markedly elevated in women who developed GDM. AST did not differ significantly between the GDM and non-GDM groups (SMD = -0.15; 95% CI: -0.66–0.37; p = 0.57). However, there is high heterogeneity in all three analyses. Subgroup analyses showed ALT levels to be significantly elevated among Asian women with GDM (SMD = 0.92; 95% CI: 0.49–1.35; p < 0.0001) and among women who were assessed during early pregnancy (SMD = 1.29; 95% CI: 0.88–1.69; p < 0.00001). ROC curve analyses revealed that ALT (AUC = 0.755) and GGT (AUC = 0.778) have a fair ability to differentiate GDM cases.

This meta-analysis further elaborated the potential of ALT and GGT enzyme tests during early pregnancy as markers for identifying women at risk. However, AST did not have a significant correlation in this case. These findings further suggest the need to evaluate the connection between hepatic alterations and the onset of GDM.