(581) Earlier diagnosis of cholestasis is associated with adverse pregnancy outcomes

Intrahepatic cholestasis of pregnancy (IHCP) is associated with adverse pregnancy outcomes including fetal demise, spontaneous preterm labor, and meconium stained amniotic fluid. Studies have yet to determine if IHCP diagnosis earlier in pregnancy is associated with higher rates of adverse outcomes.

Study Design:

Retrospective cohort study of singleton, non-anomalous live gestations complicated by IHCP at Elmhurst Hospital Center from 2005-2019. We compared rates of adverse outcomes in pregnancies complicated by early (< 32 week gestational age) versus late (≥ 32 week gestational age) diagnosis of IHCP. Primary outcome of interest was rates of spontaneous preterm labor resulting in preterm delivery. Our secondary outcomes included rates of iatrogenic preterm birth, meconium stained amniotic fluid, cesarean delivery (CD) for non-reassuring fetal heart tracing (NRFHT), umbilical artery pH < 7.20, and neonatal intensive care unit (NICU) admission. Chi-square and multivariate regression tests determined the strength of association. In all analyses, a p-value < 0.05 and 95% CI not crossing 1.00 indicated statistical significance.

Results:

Of the 1247 pregnancies complicated by IHCP, 241 (19.3%) had early diagnosis and 1006 (80.7%) had late diagnosis of IHCP. Pregnancies with early diagnosis of IHCP had higher peak total bile acid levels, higher rates of prior preterm birth, higher incidence of ursodeoxycholic acid treatment, and were delivered at an earlier gestational age. Earlier diagnosis of IHCP was associated with spontaneous preterm labor, iatrogenic preterm birth, and NICU admission. After adjusting for confounders and baseline differences including peak total bile acid levels, earlier diagnosis of IHCP remained associated with spontaneous preterm labor (OR 1.81; 95% CI 1.11-2.95), iatrogenic preterm birth, (OR 1.59; 95% CI 1.12-2.67), and NICU admission (OR 1.43; 95% CI 1.04-1.95).

Conclusion:

Findings suggests that earlier diagnosis of IHCP is associated with adverse outcomes and that this is not entirely driven by peak total bile acid levels.