If you smoke only one or two puffs occasionally during the first month of pregnancy, it often has no effect on the fetus and the pregnancy can continue. However, if smoking in large doses for a long period of time may lead to fetal malformations, such as causing anencephaly, or causing the fetus to develop congenital heart disease. Smoking in large quantities can also lead to miscarriage, premature labor or stillbirth, as well as particularly retarded intrauterine growth. This is the risk of smoking to the fetus itself, so it is advisable to terminate the pregnancy if you smoke heavily or for a long period of time. It is also recommended to protect yourself from second-hand smoke during pregnancy. Pregnant women should also refrain from smoking and drinking alcohol, which is conducive to eugenics. Regular checkups throughout the pregnancy are also very important.