In China, perinatal mother-to-child transmission is one of the important transmission routes of hepatitis B. Interruption of mother-to-child transmission is the source of hepatitis B prevention. The main maternal-infant interruption measure currently used and widely accepted is combined immunotherapy, i.e., high potency hepatitis B immunoglobulin (HBIG) injection and regular hepatitis B vaccination (0, 1, and 6 months) immediately after the birth of a newborn. However, this does not completely interrupt mother-to-child transmission, and about 90% of children with failed interruptions have HBeAg-positive mothers. This shows that serum HBV-DNA load in pregnant patients is one of the key factors in mother-to-child transmission, and effective antiviral therapy can significantly reduce the incidence of mother-to-child transmission of hepatitis B virus. One study showed that antiviral treatment with lamivudine or telbivudine in late pregnancy (28-32 weeks) significantly reduced the rate of HBsAg positivity in infants without an increase in adverse effects. Therefore, pregnant patients (especially those with HBV-DNA > 106 copies/ml) can be treated with lamivudine (100 mg/d) or telbivudine (600 mg/d) for mother-to-child transmission blockade from 28-32 weeks of gestation, provided that the benefits and risks associated with drug administration are fully understood and the pros and cons are weighed. There is no standardized time to discontinue the drug after the end of pregnancy, but in general, for perinatal MTCT only, it can be discontinued 1-3 months after delivery. However, it has been suggested that the following discontinuation criteria should be adopted: if the patient has a low baseline viral load (<104 copies/ml), discontinuation may be considered 6 months after delivery; if the patient has a high baseline viral load (≥104 copies/ml), treatment should be continued until the general patient discontinuation criteria for antiviral therapy are met.