There has not been any study showing that hepatitis B vaccination for pregnant women in the seventh to ninth month will affect fetal development, but hepatitis B vaccination during pregnancy should be avoided as much as possible, which may lead to adverse reactions in the organism. Hepatitis B vaccine is a vaccine used to prevent the organism from being infected with the hepatitis B virus, and China is a large country with hepatitis B. Hepatitis B vaccine is usually administered after birth, and if the adult’s surface antibody to hepatitis B turns negative, he or she can be vaccinated with hepatitis B vaccine under the guidance of a doctor. Usually before pregnancy, you should make sure that you have hepatitis B antibodies, if not, you should try to get vaccinated before pregnancy to prevent hepatitis B virus infection during pregnancy. Although hepatitis B vaccination during pregnancy usually does not affect the fetus, it may lead to a series of adverse reactions such as fever, which may affect the status of the pregnant woman.