Total bile acid concentrations and adverse perinatal outcomes in chinese intrahepatic cholestasis of pregnancy including asymptomatic hypercholanemia of pregnancy: a retrospective cohort study.

backgroundEvidence concerning the association between excessive total bile acid (TBA) concentrations and adverse perinatal outcomes in the recent Chinese guidelines for intrahepatic cholestasis of pregnancy (C-ICP), which recommend including asymptomatic hypercholanemia of pregnancy (AHP) in ICP management, is insufficient. This study aims to investigate the association between adverse perinatal outcomes and maternal TBA concentrations in patients with C-ICP and compare differences in adverse perinatal outcomes between AHP and ICP subgroups in different TBA concentrations.

methodsThis retrospective cohort study included pregnant individuals with C-ICP (n = 957) who delivered and had regular antenatal examination records available at a hospital in Guangzhou, China, from January 2015 to December 2024. Participants were grouped according to TBA concentrations (low mild (LM), high mild (HM), severe (S), and extremely severe (ES)) and then sub-grouped into AHP and ICP subgroups within each TBA concentration group.

resultsMultivariate logistic regression models showed that the risk of adverse perinatal outcomes (including preterm birth, indicated preterm birth, meconium-stained amniotic fluid, and admission to the neonatology department) increased with TBA concentration. Compared to the LM group, the rate of adverse perinatal outcomes increased significantly from the S group onwards, reaching its highest rate in the ES group (preterm birth: P-trend < 0.001; indicated preterm birth: P-trend < 0.001; meconium-stained amniotic fluid: P-trend = 0.037; admission to the neonatology department: P-trend < 0.001; gestational age at delivery: P-trend < 0.001; birth weight of newborn: P-trend < 0.001). However, within the ES group, there was no significant difference in the risk of adverse perinatal outcomes between the AHP subgroup and the ICP subgroups. (preterm birth: odds ratio (OR) 0.41, 95% confidence interval (CI) 0.09-2.00; indicated preterm birth: OR 0.75, 95% CI 0.14-4.06; meconium-stained amniotic fluid: OR 0.56, 95% CI 0.14-2.19; admission to the neonatology department: OR 1.65, 95% CI 0.39-7.04; gestational age at delivery: β 0.65, 95% CI - 0.42-1.72; and birth weight of newborn: β 101.7, 95% CI - 129.05-332.45).

conclusionWe recommend TBA screening in prenatal care for all pregnant women, not just for those with pruritus. In addition, the AHP population can be followed with ICP-equivalent clinical management, which is indicated when TBA concentration is ≥ 100 μmol/L, as it increases the risk of adverse perinatal outcomes.