Outcomes of infants born to women infected with hepatitis B.

BACKGROUND AND OBJECTIVES Perinatal exposure is an important mode of hepatitis B virus (HBV) transmission, resulting in chronic disease in ∼ 90% of infected infants. Immunoprophylaxis recommended for infants born to hepatitis B surface antigen-positive mothers reduces up to 95% of perinatal HBV infections. We sought to identify factors associated with perinatal HBV transmission. METHODS We analyzed prospectively collected data from 5 of 64 US-funded Perinatal Hepatitis B Prevention Programs during 2007-2013. We examined effects of maternal demographic and laboratory results, infant gestational age and birth weight, and immunoprophylactic management on perinatal HBV infection. RESULTS Data from 17,951 mother-infant pairs were analyzed. Among 9252 (51.5%) infants for whom hepatitis B surface antigen testing results were available, 100 (1.1%) acquired perinatal HBV infection. Both hepatitis B (HepB) vaccine and hepatitis B immune globulin were administered within 12 hours of birth for 10,760 (94.9%) of 11,335 infants with information. Perinatal HBV infection was associated with younger maternal age (P = .01), Asian/Pacific Islander race (P < .01), maternal hepatitis B e-antigen positivity (P < .01), maternal antibody to hepatitis B e-antigen negativity (P < .01), maternal viral load ≥ 2000 IU/mL (P = .04), and infant receipt of <3 HepB vaccine doses (P = .01). Four infants born to 429 mothers with viral load testing were infected; all 4 were born to mothers with viral loads in the ninth or tenth decile. CONCLUSIONS Perinatal HBV infection occurred among 1% of infants, most of whom received recommended immunoprophylaxis. Infants at greatest risk of infection were those born to women who were younger, hepatitis B e-antigen positive, or who had a high viral load or those infants who received <3 HepB vaccine doses.