The effect on the fetus of a major triplet carrier depends on the size of the virus. If the viral DNA quantification is less than 10^5 U/ml, the chance of intrauterine infection from the mother to the fetus is very low, less than 1%. If the viral load is 10^8 U/ml, the chance of intrauterine infection is close to 5%. However, for hepatitis B carriers with a high viral load, oral antiviral medication can be administered during the 6th month of pregnancy, and the hepatitis B vaccine and hepatitis B immunoglobulin can be administered intramuscularly after the birth of the child, which protects the fetus from hepatitis B infection by a two-pronged approach, and provides nearly 99% protection against hepatitis B in the fetus. If the liver function is abnormal, especially if the total bile acid is elevated, the bile acid can cause sudden fetal death and miscarriage through the placenta, so the liver function should be monitored regularly during pregnancy in patients with hepatitis B.