Predictive value of fasting bile acids and liver enzymes for perinatal outcomes in intrahepatic cholestasis of pregnancy

Objective: To investigate the value of fasting bile acid (FBA) levels and liver enzymes [aspartate aminotransferase (AST) and alanine aminotransferase (ALT)] in predicting adverse perinatal outcomes in intrahepatic cholestasis of pregnancy (ICP). Materials and Methods: This retrospective study included 296 pregnant women diagnosed with ICP between 2020 and 2025. Patients were classified as having mild (FBA 10-40 μmol/L, n=223) or severe ICP (FBA >40 μmol/L, n=73). Clinical, laboratory, and neonatal outcomes were compared; receiver operating characteristic (ROC) analysis was performed to evaluate the predictive value of FBA for meconium passage; and patients who received ursodeoxycholic acid (UDCA) therapy were compared with those who did not. Results: Compared with the mild ICP group, patients with severe ICP had earlier gestational ages at diagnosis and at delivery, and lower birth weight and neonatal pH (all p<0.05). FBA levels were significantly associated with fetal growth restriction (p=0.042), preterm birth (p=0.003), neonatal intensive care unit (NICU) admission (p<0.001), and meconium passage (p<0.001). AST was associated only with NICU admission and meconium passage, whereas ALT showed no significant association with perinatal complications. The median FBA level was significantly higher in patients with meconium passage (105 vs. 20 μmol/L; p<0.001). ROC analysis identified an FBA cut-off of 88.45 μmol/L (area under the curve=0.694), with 57.1% sensitivity and 81.3% specificity. Conclusion: FBA is the strongest predictor of adverse perinatal outcomes in ICP. AST provides complementary prognostic information, whereas ALT has limited predictive value. Clinical management should be guided by FBA-based risk stratification and individualized timing of delivery.