Cigarette smoking does not necessarily lead to fetal malformation, although it may lead to an increased probability of fetal malformation. Cigarettes contain harmful components to the human body, such as carbon monoxide, nicotine, etc., and pregnancy is a relatively special period of time for women, during this period if the pregnant woman smokes or is exposed to second-hand smoke, these harmful substances may pass through the placenta on the growth and development of the fetus to affect, for example, the brain will affect the development, and may even lead to fetal deformity or other abnormal conditions. Moreover, the carbon monoxide and tar in cigarettes are carcinogenic, and if a pregnant woman smokes for a long period of time or is exposed to smoking, she may also increase her chances of developing cancer, which will have an adverse effect on her health and the growth and development of her fetus. For the sake of their own health and the healthy development of the fetus, it is recommended that pregnant women do not smoke, but also to stay away from the second-hand smoke environment. Usually to scientific and reasonable diet, do not favor picky food, but also to ensure adequate sleep, do not stay up late. If there is any discomfort during pregnancy, you should go to a regular hospital in time.