Objective   To explore the effect of antiviral therapy during pregnancy on the physical growth and development of infants born to women infected with hepatitis B virus (HBV) in Guangzhou.

  Methods   A prospective cohort study was conducted for a follow up in the infants born to HBsAg-positive women recruited from May 2018 to August 2021. Children born to HBV-infected women who received antiviral therapy during pregnancy were classified as exposure group, while children born to HBV-infected mothers who received no antiviral therapy during pregnancy were classified as control group. Generalized estimating equation was used to analyze the effects of antiviral treatment during pregnancy on infant weight and length development.

  Results  A total of 663 infants born to HBV-infected women were included in this study, of whom 115 (17.35%) were divided into the exposure group and 548 (82.65%) were divided into the control group. There were no significant differences in incidences of underweight, stunting and wasting between exposure group and control group at age 1, 3, 6 and 12 months（P＞0.05）. There were no significant differences between the two groups in Z-score for age/weight, Z-score for age/length, and Z-score for length/weight. And the difference with the WHO reference standard was not statistically significant. The age/length Z-score was 0.585 times higher in the infants in exposure group than in the infants in control group (P=0.021).

  Conclusion  The antiviral treatment during pregnancy of HBV-infected women had no effect on the body weight and length of their babies in infancy.