It is possible for a pregnant woman with hepatitis B to transmit the virus to her baby. During pregnancy, if the DNA quantification of the hepatitis B virus in the bloodstream is high, it may cross the placental barrier and enter the baby’s bloodstream, so that the baby may also get hepatitis B. The quantification of hepatitis B virus is usually high at this time, and the patient is often a major triple-positive, and the DNA quantification of hepatitis B virus is usually greater than 10^6copies/ml, so measures should be taken to reduce the risk of the baby getting hepatitis B from the womb. This can be achieved by taking oral tenofovir or propofol tenofovir, two oral anti-hepatitis B virus drugs that have no effect on the fetus. It is not practical to apply other drugs at this time, because the anti-hepatitis B virus entecavir is more effective, but may cause fetal malformations.