It is well known that smoking during pregnancy has obvious risks to the health of the fetus and newborn, and to the future development of infants and children. Smoking is very common in the United States, with over 42 million estimated smokers. The prevalence of smoking among women is about 15 to 16 percent. About 11% of American women still smoke in the last trimester of pregnancy. In China, the number of deaths caused by smoking has exceeded 1 million each year. The current smoking rate among women in China is 2.4 percent, with 13 million people. Smoking among women has become a topic that cannot be ignored in the health field. Reports have found that the more mothers smoke, the more their babies lose weight. Also, the risk of spontaneous abortion, fetal death and neonatal death increases directly with maternal smoking. Long-term growth and development surveys have concluded that smoking during pregnancy affects physical growth, mental development and behavioral characteristics of children up to at least age 11. It is clear that smoking is harmful to health. All people are many people are very afraid of AIDS and do not know when to do the test after having high-risk behavior, which causes great harm to physical and mental health and seriously affects work, study and life. The following is provided in the form of science and technology to the majority of friends, hope to bring you help. You should quit smoking. For women who are planning to become pregnant, quitting smoking can be very helpful to the health of the fetus and newborn, as well as the future development of the infant. The respiratory side effects of smoking include reduced lung function, increased respiratory symptoms in infancy, and increased risk of childhood asthma and COPD. Some studies have shown that pregnant women who smoke can reduce the respiratory effects of maternal smoking on their infants if they quit early in pregnancy. Recently, to study the effects of vitamin C on the respiratory system of infants born to mothers who smoked during pregnancy, McEvoy and his colleagues conducted a randomized, double-blind, placebo-controlled clinical study and published their findings in the journal JAMA. The researchers randomized 159 women who smoked during pregnancy to a placebo group (n = 83) and a vitamin C group (n = 76) and looked at respiratory symptoms in infants born to mothers in both groups. It was found that infants born to mothers in the vitamin C group had significantly better lung function in the first week of life than infants born to mothers in the placebo group. The prevalence of asthma was also significantly lower in the vitamin C group than in the placebo group during the first year of life and was similar to that of infants born to nonsmoking mothers. However, there was no significant difference in lung function between the vitamin C group and the placebo group 1 year after birth. Thus, for women who smoked during pregnancy, vitamin C could be a way to mitigate the harms of smoking and protect the health of the newborn as well as the future development of the infant. However, there is still no definitive answer as to whether vitamin C supplementation can completely reverse the effects of maternal smoking during pregnancy on the fetus or newborn. However, quitting smoking remains a top goal for women who are preparing to become pregnant and who smoke. By quitting, mothers-to-be can effectively protect their children’s health by preventing fetal and neonatal exposure to tobacco. This is more effective than any amount of vitamin C.