Screening and Management of Cholestasis of Pregnancy
Initial Screening Approach
Any pregnant woman presenting with new-onset pruritus in the second or third trimester should be immediately tested with serum total bile acids and liver transaminases (ALT/AST), using random (non-fasting) samples for convenience. 1, 2
Key Clinical Features to Assess
- Pruritus characteristics: Generalized itching predominantly affecting palms and soles, worse at night, without a primary rash (only excoriations from scratching) 1, 2
- Timing: Typically occurs in late second or third trimester 1, 2
- Physical examination: Absence of rash, vesicles, bullae, or plaques; dark urine and jaundice are uncommon and suggest alternative diagnoses 1
- Risk factors: Prior ICP (up to 90% recurrence risk), family history, pre-existing liver disease (hepatitis C, cirrhosis, gallstones) 1, 2
Essential Laboratory Testing
Order immediately when ICP is suspected: 1, 2
- Total serum bile acids (enzymatic assay preferred; results in 4 hours to 4 days vs. 4-14 days for mass spectrometry) 1, 2
- Liver transaminases (ALT and AST) 1, 2
Diagnostic threshold: Total bile acids >10 μmol/L combined with pruritus confirms ICP 1, 2
Additional testing to exclude alternative diagnoses: 2
- Complete blood count with platelets (exclude HELLP syndrome)
- Coagulation studies and glucose (exclude acute fatty liver of pregnancy)
- Hepatobiliary ultrasound (exclude gallstones/biliary obstruction)
- Thyroid function tests and renal function (if indicated)
Management Algorithm Based on Bile Acid Levels
Treatment Initiation
Start ursodeoxycholic acid (UDCA) 10-15 mg/kg/day in divided doses immediately upon diagnosis, titrating up to maximum 21 mg/kg/day if needed. 1, 2 UDCA improves maternal pruritus, reduces bile acid levels, and decreases adverse outcomes including preterm birth and stillbirth. 2
Fetal Surveillance
Begin antenatal fetal testing at the gestational age when delivery would be performed in response to abnormal results, or immediately if diagnosed later in gestation. 1, 2 Increase frequency with higher bile acid levels, especially ≥100 μmol/L. 2 Place all ICP patients on continuous fetal monitoring during labor. 2
Delivery Timing (Strictly Based on Peak Bile Acid Levels)
Bile acids ≥100 μmol/L: Deliver at 36 0/7 weeks of gestation 1, 2, 3
Bile acids <100 μmol/L: Deliver between 36 0/7 and 39 0/7 weeks of gestation 1, 2
Bile acids <40 μmol/L: Consider delivery at term (39 weeks) 2
Administer antenatal corticosteroids for fetal lung maturity if delivering before 37 0/7 weeks. 1
Critical Management Pitfalls to Avoid
Never deliver before 37 weeks based on clinical suspicion alone without laboratory confirmation of elevated bile acids. 1, 2, 3 This leads to unnecessary preterm deliveries with associated neonatal morbidity. 3
Never assume normal initial labs permanently rule out ICP. 3 Pruritus can precede bile acid elevation by several weeks. 1, 2
Repeat Testing Strategy
If initial bile acids are normal but pruritus persists without alternative explanation, repeat bile acid and transaminase measurements every 1-2 weeks until symptoms resolve or diagnosis is confirmed. 2, 3 Bile acid levels can increase rapidly during pregnancy, particularly near term. 1, 3
Serial weekly testing is not routinely recommended once diagnosis is established, but repeat testing may guide delivery timing in severe cases. 1
Postpartum Follow-Up
Repeat biochemical testing at 4-6 weeks postpartum if symptoms or abnormal laboratory values persist. 1, 2, 3 ICP typically resolves completely after delivery; persistence suggests underlying chronic liver condition (chronic hepatitis, liver fibrosis/cirrhosis, hepatitis C, cholangitis). 1
Refer to hepatology if results remain abnormal at 4-6 weeks postpartum. 1, 2, 3 Some experts advocate routine hepatitis C testing in all ICP patients given the increased risk and availability of effective treatment. 1