Smoking during pregnancy has a certain effect on the fetus, but if all the results of the maternity test are normal, the child can continue to have, without too much anxiety. However, care should be taken to avoid continuing to smoke, as well as avoiding second-hand smoke, developing good dietary and living habits, paying attention to hygiene, relaxing, and going to the hospital for regular checkups. Tobacco contains more than 400 kinds of harmful substances, including nicotine, cyanide compounds, carbon trioxide and other substances that are more harmful to the human body. Whether you actively smoke during pregnancy or passively inhale second-hand smoke, you may increase the risk of miscarriage, preterm labor, fetal anoxia and malformation, tic disorders, asthma and other diseases. Smoking a lot of harmful substances will act on the endings of blood vessels, so that blood vessels constriction, affecting the exchange of oxygen between the fetus and the mother, compared to normal non-smoking pregnant women, will greatly increase the incidence of intrauterine asphyxia of the fetus. In conclusion, smoking during pregnancy is more harmful to mother and baby, but if the pregnancy test is comprehensive and the test results are not abnormal, the fetus can be delivered normally.