OBJECTIVE: To estimate the feasibility and immunogenicity of an accelerated hepatitis B vaccination schedule of 0, 1, and 4 months in high-risk pregnant women.
METHODS: We conducted a prospective clinical trial of high-risk pregnant women who were hepatitis B surface antigen-negative at presentation for prenatal care. A detailed questionnaire was administered and eligible women received a hepatitis B vaccine intramuscularly on a 0-, 1-, and 4-month schedule. Adverse reactions and hepatitis B surface antigen seroconversion rates were documented. Factors influencing seroconversion were determined.
RESULTS: Two hundred high-risk pregnant women were enrolled; 84% completed the three-dose vaccine series. Seroconversion (hepatitis B surface antigen 10 milli-international units/mL or greater) after one dose was 56% (95% confidence interval [CI], 49–63%), 77% (95% CI, 71–83%) after two doses, and 90% (95% CI, 85–94%) after completing three doses. Body mass index was inversely associated with seroconversion rates (P<.001). There was no single body mass index above which seroconversion did not occur. There were no serious adverse events; injection site discomfort was the most prevalent complaint (10.5%).
CONCLUSION: An accelerated hepatitis B vaccination schedule at 0, 1, and 4 months in high-risk pregnant women is effective, practical, and well tolerated. This accelerated vaccine strategy can be completed during the course of pregnancy and provides another means of decreasing hepatitis B virus disease and transmission.
LEVEL OF EVIDENCE: II