Men are not allowed to have children while taking the drug entecavir. Entecavir is an antiviral drug that is mainly used to treat hepatitis B. If a woman wants to get pregnant and have a child, it is best to prepare for pregnancy only after three months of entecavir withdrawal. If she gets pregnant while taking the drug, it is easy to adversely affect the development of the embryo, and it can also lead to malformations. From the point of view of eugenics, women should adjust their bodies during the preparatory period not to take drugs indiscriminately. Also pay attention to avoid the adverse effects of bacteria, viruses, radiation, etc., to maintain a relaxed mood, appropriate exercise to enhance the body’s physical fitness, in preparation for pregnancy. And in the preparation period also need to take a small dose of folic acid tablets, to prevent fetal malformation.