To investigate the effect of telbivudine on mother-to-child blockade of pregnant women infected with hepatitis B virus (HBV) and the influence on the immune response to hepatitis B vaccine of infants.

The pregnant women with HBV DNA > 2.0 × 10⁵ IU/ml during the middle of the pregnancy and their infants were recruited from Beijing Ditan Hospital, Capital Medical University from October 1st, 2017 to December 30th, 2019, among them, 132 patients who were given telbivudine during middle and late pregnancy were collected as study group, and 70 pregnant women who did not take antiviral drugs excluding 3 cases with mother-to-child block failure were collected as control group (67 cases). All the neonates of pregnant women were injected with recombinant hepatitis B vaccine (10 μg) and hepatitis B immunoglobulin (100 IU) within 2 hours after birth, and followed by routine injection of the recombinant hepatitis B vaccine 1 month and 6 months after birth. Microticle chemiluminescence method was used to detect HBV surface antibody (HBsAb) titer in 1-year-old children, and the immune responses of children to hepatitis B vaccine were compared between the two groups by non-parametric rank sum test. The measurement data with normal distribution of the pregnant women and their newborns were analyzed by independent sample t-test and the measurement data without normal distribution were analyzed by non-parametric test; count data were analyzed by Pearson chi-square test or continuously corrected chi-square test.

Among the 202 pregnant women, the mother-to-child blockade failure rates between pregnant women treated with telbivudine or not were significantly different (0 vs. 4.29%: χ² = 5.74, P = 0.017). There were no statistical differences in age (t =-1.62, P = 0.110), number of pregnancies (t = 0.27, P = 0.787), number of births (t = 1.325, P = 0.187), body weight (t = 0.55, P = 0.580), alanine transaminase (ALT) (Z =-0.19, P = 0.850), and HBV DNA load (t = 0.49, P = 0.620), cesarean section rate (χ² = 0.71, P = 0.400) and complications during pregnancy and perinatal period between cases in study group and control group. The difference of HBV DNA load before delivery between the two groups was statistically significant (t = 31.88, P < 0.001). There were no statistical differences in gestational weeks of birth (t = 1.72, P = 0.09), body length (t = 0.39, P = 0.696), birth weight (t =-0.13, P = 0.900), sex ratio (χ² = 0.25, P = 0.620), Apgar score (t = 0.213, P = 0.832) between the two groups of neonates, and no statistical difference in weight (t =-0.20, P = 0.840), ALT (Z =-0.40, P = 0.690) and HBsAb (Z = 0.76, P = 0.450) between the two groups of infants at 1-year-old. No response rate, low response rate and stong response rate to hepatitis B vaccine were 3.79% (5/132), 22.73% (30/132) and 73.48% (97/132) of 1-year-old children in study group, respectively, which were 0 (0/67), 14.93% (10/67) and 85.07% (57/67) in control group, wihout statistical difference (Z =-1.93, P = 0.054).

Telbivudine treatment during pregnancy could significantly improved the successful rate of mother-to-child blockade by reducing maternal HBV DNA load and did not affect the immune response to hepatitis B vaccine of infants.