The normal thickness of the uterine scar is 0.3cm or more. The scar will be left after the excision of fibroids or uterine cesarean section. After pregnancy, as the fetus grows, the muscle layer at the uterine scar becomes less elastic and cannot stretch well, and it will become thinner, which in serious cases may lead to rupture of the pre-uterus or rupture of the uterus and pose a threat to the life of the pregnant woman and the fetus. Women who have had a uterine scar should pay attention to proper rest during pregnancy and have ultrasound done dynamically to check the thickness of the muscles in the uterine scar, if the thickness of the muscles in the scar is less than 0.2cm, accidents are likely to occur and appropriate treatment measures should be taken as soon as possible. When a woman has had uterine scar surgery, she needs an interval of more than two years before she can get pregnant.