Filling cavities is usually not recommended during pregnancy, but if a toothache is so severe that it must be filled, it can be done in mid-pregnancy as prescribed by the doctor. If a pregnant woman uses anesthetic drugs during the filling process, it may affect the development of the fetus’s nervous system. If anesthesia is not used, the pregnant woman will feel pain again during the filling, and severe pain will stimulate uterine contractions leading to miscarriage. Especially in early pregnancy, is not conducive to the development of the gestational sac and embryo, once the damage to the gums, periodontal and other tissues caused by inflammation, but also the use of anti-inflammatory drugs to control the infection, is not conducive to the growth and development of the fetus. If a pregnant woman with severe toothache must be filled, it is best to choose in the middle of pregnancy when the fetus is relatively stable, that is, 4 to 6 months of pregnancy to fill. At this time, you can take a simple filling method under the guidance of the doctor, do not blindly use medicine. Pregnant women who have a severe toothache and need to fill a cavity, it is recommended to go to a regular hospital dentistry, operated by a professional doctor, so as not to cause harm to the fetus.