What is the management for pruritus in the second trimester of pregnancy?

Management of Pruritus in Pregnancy During Second Trimester

For pruritus during the second trimester of pregnancy, first rule out intrahepatic cholestasis of pregnancy (ICP) with serum bile acid testing, then treat with ursodeoxycholic acid (10-15 mg/kg/day) if ICP is confirmed, or use low to mid-potency topical corticosteroids for symptomatic relief if ICP is excluded.

Diagnostic Approach

Initial Evaluation

• Conduct a thorough assessment to differentiate between:
  • Pregnancy-specific dermatoses
  • Pre-existing skin conditions
  • Benign hormonal changes

Key Diagnostic Steps

1. Laboratory testing:

   • Serum bile acid levels (most sensitive indicator for ICP)
   • Liver function tests (ALT, AST, bilirubin, GGT)
   • Prothrombin time/INR if coagulopathy suspected 1

2. Physical examination findings to note:

   • Distribution of pruritus (generalized vs. localized)
   • Presence or absence of rash
   • Excoriations from scratching 1

3. Important clinical patterns:

   • ICP: Pruritus without primary rash (may have excoriations), often affects palms and soles, worse at night 1
   • Atopic eruption of pregnancy (AEP): Eczematous rash on face, neck, flexural areas 1
   • Polymorphic eruption of pregnancy (PEP): Urticarial papules and plaques on abdomen and proximal thighs 1
   • Pemphigoid gestationis: Vesicles and bullae 1

Management Algorithm

If ICP is Suspected or Confirmed (Bile acids ≥10 μmol/L)

1. First-line treatment:

   • Ursodeoxycholic acid (UDCA) 10-15 mg/kg/day in divided doses 1
   • UDCA improves pruritus in 67-80% of patients and may reduce adverse fetal outcomes 1

2. For refractory pruritus:

   • Increase UDCA dose up to 25 mg/kg/day 1
   • Consider adding:
     • S-adenosyl-L-methionine (may have additive effect with UDCA) 1
     • Rifampicin (for severe cases) 1
     • Cholestyramine (caution: may exacerbate vitamin K deficiency) 1

3. Monitoring:

   • Serial bile acid measurements
   • Liver function tests
   • Fetal monitoring based on bile acid levels 1

If ICP is Excluded (Normal bile acids)

1. For mild to moderate pruritus:

   • Low to mid-potency topical corticosteroids (e.g., hydrocortisone)
   • Apply to affected areas up to 3-4 times daily 2
   • Avoid extensive use of high-potency corticosteroids (associated with low birth weight) 3

2. Supportive measures:

   • Mild soaps and lukewarm water for bathing
   • Topical emollients (safe but efficacy unknown) 1
   • Cool compresses
   • Loose-fitting cotton clothing

3. For moderate to severe symptoms:

   • Oral antihistamines (considered safe in pregnancy) 4
   • Oatmeal baths

Special Considerations

Risk Stratification Based on Bile Acid Levels

• <40 μmol/L: Lower risk, similar fetal outcomes to women without ICP 1
• 40-99 μmol/L: Moderate risk (0.3% IUFD risk) 1
• ≥100 μmol/L: High risk (3.4% IUFD risk) - requires closer monitoring 1

Important Caveats

• Pruritus can precede laboratory abnormalities by several weeks - repeat testing if clinical suspicion remains high 5
• If initial bile acid testing is normal but pruritus persists, repeat testing in 1-2 weeks 5
• Persistent symptoms or abnormal liver tests beyond 6 weeks postpartum warrant evaluation for underlying chronic liver disease 1

Fetal Considerations

• ICP and pemphigoid gestationis are associated with adverse fetal outcomes including prematurity and stillbirth 6
• Other pregnancy-specific dermatoses (AEP, PEP) typically do not affect the fetus 4

By following this systematic approach, clinicians can effectively diagnose and manage pruritus during the second trimester of pregnancy, ensuring optimal outcomes for both mother and fetus.