Chronic Hepatitis B in Pregnancy: Diagnosis and Management
All pregnant women must be screened for HBsAg in the first trimester, and those with HBV DNA >200,000 IU/mL or who are HBeAg-positive should receive tenofovir disoproxil fumarate starting at 24-28 weeks gestation through 12 weeks postpartum to prevent mother-to-child transmission. 1
Diagnosis and Screening
Universal Screening Protocol
- Screen all pregnant women for HBsAg at the initial prenatal visit 1
- If previous triple-panel testing (HBsAg, anti-HBs, anti-HBc) was documented negative, screen with HBsAg alone 2
- For unknown status at delivery, test immediately upon admission to the birthing facility 2
Diagnostic Workup for HBsAg-Positive Women
Once HBsAg-positive status is confirmed, obtain:
- HBV DNA viral load (critical for treatment decisions) 3, 2
- HBeAg status 1
- Liver biochemical tests (ALT/AST) 4
- Assessment of liver fibrosis status 4
The 2023 EASL guidelines provide the most comprehensive and recent framework, establishing clear viral load thresholds that directly impact clinical management.
Antiviral Treatment During Pregnancy
Treatment Indications
Start tenofovir disoproxil fumarate (TDF) at 24-28 weeks gestation in:
- HBV DNA >200,000 IU/mL (>5.3 log₁₀ IU/mL) 1
- HBeAg-positive pregnant women (regardless of viral load) 1
- Advanced fibrosis or cirrhosis (continue if already on treatment; initiate if not) 1
Dosing and Duration
- TDF 300 mg daily or tenofovir alafenamide (TAF) 25 mg daily 2
- Continue through 12 weeks postpartum 1
- TDF is the first-line agent with extensive safety data 2, 4, 5
Critical Caveat
Do NOT administer hepatitis B immunoglobulin (HBIG) to pregnant women - it is ineffective at reducing mother-to-child transmission regardless of maternal viral load 1. This represents a key pitfall where outdated practices persist.
Delivery Management
Mode of Delivery
- Vaginal delivery is recommended - cesarean section does NOT reduce HBV transmission when neonatal immunoprophylaxis is provided 1
- Exception: Consider cesarean only in Asian HBeAg-positive women with HBV DNA >7 log₁₀ copies/mL (6.14 log₁₀ IU/mL) who did NOT receive antiviral therapy 1
- Base delivery decisions on obstetric indications, not HBV status 2, 5
Invasive Prenatal Testing
- Counsel HBeAg-positive women or those with HBV DNA >5.3 log₁₀ IU/mL about increased transmission risk with amniocentesis 1
- Prefer non-invasive prenatal testing when available 1
- If amniocentesis necessary, can proceed after informed consent 2, 5
Neonatal Management
All infants born to HBsAg-positive mothers must receive:
- HBV vaccine within 12 hours of birth 1, 2, 5
- HBIG within 12 hours of birth 1, 2, 5
- This applies regardless of whether mother received antiviral therapy 2, 5
Breastfeeding
Breastfeeding is safe and should be encouraged in all HBsAg-positive mothers, including those on TDF treatment 1. The only contraindications are:
Postpartum Monitoring
For Mothers on Antiviral Therapy
- Monitor ALT every 1-3 months for 6 months postpartum 4
- Watch for hepatitis flares after delivery and after TDF discontinuation 4, 6
- Women with cirrhosis should continue TDF indefinitely 1
For Infants
- Complete HBV vaccination series per schedule 4
- Serologic testing at 9-12 months of age to confirm immunity (anti-HBs) and absence of infection (HBsAg negative) 4
Key Algorithmic Approach
- First trimester: Screen all women for HBsAg
- If HBsAg-positive: Check HBV DNA and HBeAg
- If HBV DNA >200,000 IU/mL OR HBeAg-positive: Start TDF at 24-28 weeks
- At delivery: Administer HBV vaccine + HBIG to infant within 12 hours
- Postpartum: Continue TDF for 12 weeks (unless cirrhosis—then indefinitely)
- Monitor: ALT every 1-3 months for 6 months; infant serology at 9-12 months
This evidence-based approach, primarily from the 2023 EASL guidelines with 100% consensus on key recommendations, provides the clearest pathway to preventing mother-to-child transmission while maintaining maternal and infant safety.