Smelling tobacco is not recommended for pregnant women. The smell of tobacco can be harmful to pregnant women. Some studies have pointed out that the smell of tobacco has tar, ammonia, nicotine, suspended particles, PM2.5, polonium-210 and other harmful chemicals, especially nicotine in the smoke, which has a significant detrimental effect on the reproductive function, sperm, eggs and embryos, such as it will lead to low intellectual development of the fetus, teratogenicity, carcinogenicity and so on. Pregnant women are advised not to smoke or smell smoke during the whole period of pregnancy. They should pay attention to rest, eat a reasonable diet, and also eat a variety of high-protein foods to supplement the nutritional needs of the body. Pregnant women should go to the hospital regularly for obstetric examination to assess the growth and development of the fetus, and go to the hospital at any time if they feel uncomfortable.