Liver function, HBV serology, and HBV DNA of the children were evaluated at 7–8 months of age. No HBsAg-positive cases were found, and vertical transmission was successfully blocked in 54 infants, for a blocking rate of 100%. A quantitative HBV surface antibody (anti-HBs) test revealed effective vaccination (anti-HBs-positive) in 53 infants in our study, with maximum and minimum titers of 1000 and 127.21 mIU/l, respectively. The effective vaccination rate of the infants in our study was 98.15% (53/54), with no differences between the early-pregnancy treatment and late-pregnancy treatment groups (p > 0.05). Only one infant whose parents were both chronic HBV-infected and whose mother had taken LdT throughout her pregnancy was anti-HBs-negative, and the vaccination failed. After enhanced HBV vaccination at age 8 months, the infant's anti-HBs titer increased to 127.8 mIU/ml at 12 months of age.