Does breastfeeding require a delay in Hepatitis B (Hep B) vaccination?

From the Guidelines

No, breastfeeding does not require a delay in Hepatitis B (Hep B) vaccination. According to the most recent and highest quality study, infants born to HBsAg-positive mothers can be breastfed immediately after birth, and the HepB vaccine series should be completed according to the recommended schedule 1. The study emphasizes that infants who are born to HBsAg-positive mothers and receive postexposure prophylaxis may be breastfed beginning immediately after birth.

Key Points

• The HepB vaccine is considered safe during breastfeeding and does not affect milk production or harm the nursing infant.
• Breastfeeding mothers can receive the vaccine at any time without interrupting breastfeeding.
• The vaccine contains no live virus, only proteins that stimulate immunity against the hepatitis B virus.
• These proteins do not pass into breast milk in significant amounts, and even if they did, they would be digested in the baby's stomach and would not cause infection or harm.
• Vaccination during breastfeeding actually provides an added benefit, as it helps protect the mother from hepatitis B infection, which in turn reduces the risk of transmission to the baby through close contact.

Recommendations

• Infants born to HBsAg-positive mothers should receive HepB vaccine and HBIG within 12 hours of birth, administered at different injection sites.
• The final dose in the series should not be administered before age 24 weeks (164 days).
• Postvaccination serologic testing for anti-HBs and HBsAg should be performed after completion of the vaccine series at age 9–12 months.
• HBsAg-negative infants with anti-HBs levels ≥10 mIU/mL are protected and need no further medical management, as stated in the study 1.

Breastfeeding and Vaccination

• Infants born to mothers with unknown HBsAg status may be breastfed beginning immediately after birth, as mentioned in the study 1.
• Breastfeeding does not interfere with the immunogenicity of the HepB vaccine, and the vaccine does not affect milk production or harm the nursing infant.

From the Research

Hepatitis B Vaccination and Breastfeeding

• The studies 2, 3, 4 suggest that breastfeeding does not increase the risk of Hepatitis B (HBV) infection in infants who have received proper immunoprophylaxis at birth.
• A meta-analysis 2 found that the difference in risk of HBV infection between breastfed and formula-fed infants was -0.8% (95% confidence interval: -1.6%, 0.1%).
• Another study 3 found that breastfeeding was not associated with HBV infection in children, adjusting for the effect of maternal HBeAg status and other factors.
• A more recent meta-analysis 4 also found no significant difference in the risk of HBV infection between breastfed and non-breastfed infants after proper immunoprophylaxis.

Timing of Hepatitis B Vaccination

• The American Academy of Pediatrics and the Centers for Disease Control and Prevention recommend delaying the initiation of hepatitis B immunization beyond the first week of life for premature infants at low risk for hepatitis B infection, particularly in newborns weighing <1700 g at birth 5.
• However, the studies do not suggest that breastfeeding requires a delay in Hepatitis B vaccination, as long as the infant has received immunoprophylaxis at birth 6, 4.
• In fact, the Society for Maternal-Fetal Medicine recommends that individuals with HBV infection can breastfeed as long as the infant has received immunoprophylaxis at birth 6.

Breastfeeding and HBV Transmission

• The studies 2, 3, 4 consistently show that breastfeeding does not increase the risk of HBV transmission from mother to child, as long as the infant has received proper immunoprophylaxis.
• The results suggest that mothers carrying HBV can breastfeed their babies after proper immunoprophylaxis in the infants 4.