Pregnancy smell of coal, if not for a long time, or smell a few hours, pregnant women appear brief dizziness, nausea and other discomfort, will not lead to fetal malformation do not worry. If you smell gas for a long time, it will have a certain effect on the fetus, because smelling gas for a long time can easily cause carbon monoxide poisoning, causing symptoms such as hypoxia in pregnant women, which can also lead to intrauterine hypoxia in the fetus, which can easily affect fetal brain development and lead to fetal malformations in serious cases. If you have gas poisoning during pregnancy, it is best to have regular maternity checks, such as Down’s syndrome screening and 4D ultrasound, to determine whether the fetus is developing normally, and if the fetus is developing normally, don’t worry. It is best to pay attention to indoor window ventilation during pregnancy, if the indoor smell of gas is best not to live, pregnancy is a special period, if improper care will affect the baby’s development.