Root canal treatment is generally not recommended in pregnancy, but if the toothache is severe or the tooth is severely damaged, fillings can be done in the middle 4-6 months of pregnancy, early and late pregnancy may lead to miscarriage and preterm labor and other conditions. In early pregnancy, the fetus has just landed on the bed, and the hormone fluctuation in the pregnant woman’s body is large, the fetus is unstable as well as the pregnant woman may have early pregnancy reaction such as vomiting, it is not suitable for root canal treatment this kind of traumatic surgery, if the use of root canal treatment, the pregnant woman due to the pain and too much tension is likely to lead to preterm miscarriage or miscarriage and other situations. In late pregnancy, the fetus is fully developed. The pain as well as the psychological pressure during root canal treatment may cause the uterine muscles to contract, leading to the early birth of the fetus and the risk of preterm labor, which may be complicated with a series of adverse effects, and so it is not recommended to have the treatment in late pregnancy either. If the toothache is very severe or the tooth is extremely damaged, treatment is recommended in mid-pregnancy when the fetus and the pregnant woman are relatively stable, but a complete evaluation by the doctor is required before determining whether or not to treat.