Can IHCP Lead to Preterm Delivery?
Yes, intrahepatic cholestasis of pregnancy (ICP) is definitively associated with preterm delivery, both spontaneous and iatrogenic, and this represents a significant fetal complication of the condition. 1
Direct Association with Preterm Delivery
ICP carries substantial risk for the fetus, with preterm delivery being one of the three major complications alongside meconium-stained amniotic fluid and stillbirth. 1 This association is well-established across multiple authoritative guidelines and represents a core feature of the disease's natural history. 1, 2
The preterm delivery risk manifests in two distinct ways:
- Spontaneous preterm delivery occurs as a direct consequence of the disease process itself 2, 3
- Iatrogenic preterm delivery is recommended as part of evidence-based management to prevent stillbirth, particularly in severe cases 1
Management-Related Preterm Delivery
The Society for Maternal-Fetal Medicine provides clear, algorithmic guidance on timing of delivery that necessarily involves preterm birth in many cases:
For Severe ICP (Bile Acids ≥100 μmol/L):
- Delivery at 36 0/7 weeks is strongly recommended (GRADE 1B), as stillbirth risk increases substantially at this gestational age 1
- This represents planned preterm delivery to prevent fetal mortality 1
For Moderate ICP (Bile Acids <100 μmol/L):
- Delivery between 36 0/7 and 39 0/7 weeks is recommended (GRADE 1C) 1
- Women with bile acids 40-99 μmol/L should be delivered toward the earlier end of this range 1
- Women with bile acids <40 μmol/L can be managed toward 39 weeks 1
Earlier Preterm Delivery (34-36 weeks):
Delivery between 34-36 weeks should be considered for women with bile acids ≥100 μmol/L who have: 1
- Excruciating, unremitting pruritus unrelieved by pharmacotherapy
- History of stillbirth before 36 weeks from ICP in a previous pregnancy
- Preexisting or acute hepatic disease with worsening function
Supporting Fetal Lung Maturity
Antenatal corticosteroids for fetal lung maturity are strongly recommended (GRADE 1A) for all patients delivering before 37 0/7 weeks if not previously administered. 1 This recommendation acknowledges that preterm delivery is an expected management strategy for ICP.
Clinical Context
The mechanism underlying spontaneous preterm delivery in ICP relates to bile acid toxicity effects, including increased fetal gut motility leading to meconium passage and potential triggering of labor. 1 The American College of Obstetricians and Gynecologists recommends delivery at 36-37 weeks or at diagnosis if after 37 weeks, explicitly balancing the risks of iatrogenic prematurity against stillbirth risk. 1
Important caveat: Preterm delivery at <37 weeks is strongly recommended AGAINST (GRADE 1B) in patients with only clinical suspicion of ICP without laboratory confirmation of elevated bile acids. 1 Diagnostic certainty is essential before subjecting the fetus to prematurity risks.
The preterm delivery rate in ICP is substantial enough that recent improvements in perinatal outcomes are attributed to "late preterm or early-term delivery" combined with intensive fetal surveillance. 1