Smelling fumes while pregnant generally has no effect on the fetus. The fetus absorbs nutrients through the umbilical cord and placenta in the uterine cavity, and pregnant women will not release the fumes to the fetus after smelling the fumes, so there is generally no effect on the fetus. However, prolonged sniffing of fumes will stimulate the respiratory tract of pregnant women, which may cause coughing, sneezing or sore throat and other uncomfortable symptoms, which may have a certain impact on pregnant women. It should be noted that some pregnant women may experience aggravation of pregnancy reactions such as vomiting after being stimulated by fumes, and it is not recommended that pregnant women smell fumes for a long period of time during pregnancy in order to avoid the occurrence of uncomfortable symptoms on their own.