In China, with the implementation of the Maternal and Child Health Law, the Law on Prevention and Control of Infectious Diseases, and the prevention of mother-to-child transmission of AIDS, syphilis, and hepatitis B, the rate of hepatitis B virus infection among twelve-year-olds in China is not high. 1. Pregnancy: at present, pregnant women during pregnancy are routinely tested for hepatitis B markers, and pregnant women with hepatitis B who are eligible for antiviral treatment are given antiviral treatment in late pregnancy with informed consent. 2. Newborns: newborns born to HBsAg-negative pregnant women should be injected with hepatitis B vaccine according to the immunization procedure after birth, and newborns born to HBsAg-positive pregnant women should be immunized with hepatitis B immunoglobulin and hepatitis B vaccine as early as possible after birth. 3. Follow-up: 1~2 months after the completion of the last dose of hepatitis B vaccine, the newborns will be tested for hepatitis B serological markers to know whether the prevention is successful or not. With the above work, the rate of hepatitis B virus infection at the age of twelve is not high in China at present, but attention should be paid to the need for regular review.