Early induction of labor in high-risk intrahepatic cholestasis of pregnancy: what are the costs?

Abstract

Purpose: Induction of labor among pregnant women with high levels of total bile acid (TBA) is common among clinicians. We examined, if women with intrahepatic cholestasis of pregnancy (ICP) and TBA ≥ 40 μmol/l have a higher risk of maternal-fetal complications, when labor is induced at 37 weeks of gestation, compared with induction of labor at term in women with low-risk ICP.

Methods: Retrospective cohort study of 16,185 women delivering at Roskilde University Hospital in the period 2006-2011. Women with high-risk ICP (TBA ≥ 40 μmol/l) had labor induced at 37 weeks of gestation; women with low-risk ICP (TBA < 40 μmol/l) at term.

Outcomes: Mode of delivery, duration of induction procedures, highest level of TBA and alanine aminotransferase (ALT) and for the neonates: Apgar scores at 5 min, umbilical cord pHs and SBEs, NICU admissions and birthweights.

Results: The incidences of ICP was 1.2 % (95 % CI 1.05-1.39 %) altogether and for high-risk ICP 0.4 % (95 % CI 0.27-0.46 %). No difference was found in mode of delivery, length of induction of labor nor in neonatal outcomes, except for an expected difference in birthweight. In high-risk ICP, ALT was not raised in 10.3 % (95 % CI 2.5-18.2 %).

Conclusion: Early induction of labor at 37 weeks of gestation seems justified in high-risk ICP, as, except for abbreviating gestational age by 9 days with 296 g smaller babies, induction of labor was not followed by detectable maternal-fetal disadvantages and is favored by an expected major reduction in ICP stillbirth risk.

Keywords: Cesarean section; Induction of labor; Intrahepatic cholestasis of pregnancy; Total bile acid concentration.