The Efficacy of Two Different Dosages of Hepatitis B Immunoglobulin Combined with Hepatitis B Vaccine in Preventing Mother-to-child Transmission of Hepatitis B Virus: A Prospective Cohort Study

Background/aims: A birth dose of hepatitis B immunoglobulin (HBIG), in combination with hepatitis B vaccine (HepB), is recommended for infants born to hepatitis B surface antigen (HBsAg)-positive mothers. However, the optimal dosage of HBIG remains to be resolved. This prospective cohort study aimed to compare the efficacy of two dosages of HBIG combined with HepB to prevent mother-to-child transmission (MTCT) of HBV.

Methods: From 2009 to 2011, we prospectively enrolled mother-infant pairs with positive maternal HBsAg in China. Infants were assigned to receive one dose of 100 IU or 200 IU HBIG within 12 h of birth according to maternal numbering, followed by completion of the 3-dose 10 μg HepB series. At 7 months, post-vaccination serologic testing (PVST) was performed in 545 and 632 infants in 100 IU and 200 IU HBIG groups, respectively, among whom, 451 and 529 were followed up to 12 months.

Results: Maternal and birth characteristics were comparable between infants in 100 IU and 200 IU HBIG groups. At 7 months, the rates of perinatal infection were 1.5% (8/545) and 1.9% (12/632) in 100 IU and 200 IU HBIG groups, respectively (p = .568). One non-responder infant in 200 IU HBIG group became newly infected at 12 months. The antibody to hepatitis B surface antigen (anti-HBs) positive rates were 98.5% (529/537) and 98.2% (609/620) in 100 IU and 200 IU HBIG groups at 7 months, respectively (p = .704), and the corresponding figures were 98.2% (431/439) and 97.1% (496/511) at 12 months (p = .266). The anti-HBs geometric mean concentrations were comparable between two groups at 7 months (707.95 mIU/mL vs. 602.56 mIU/mL, p = .062) and 12 months (245.47 mIU/mL vs. 229.09 mIU/mL, p = .407).

Conclusions: One birth dose of 100 IU HBIG, combined with the HepB series, might be enough for preventing MTCT of HBV in infants born to HBsAg-positive mothers.