If a woman has a short cervix, or if she has undergone a cervical conization procedure before pregnancy, she may have a short cervix during pregnancy, resulting in cervical insufficiency and causing preterm labor or preterm delivery. For women who are considered to have cervical insufficiency due to a short cervix detected by ultrasound in the middle of pregnancy, cervical cerclage is often considered to be the appropriate treatment to preserve the pregnancy, with a success rate of about 50%. This is because in many women with cervical insufficiency, even if they undergo cervical ligation, they may still have preterm labor and fail to keep the baby, so it is not always possible to keep the baby after cervical ligation. After cervical cerclage, as long as the cervix does not shorten further and the opening of the uterus does not widen, as well as the signs of labor with contractions, it means that the pregnancy is successfully preserved, and the survival rate of the fetus will increase significantly with the increase of the gestational weeks. As long as the fetus can be preserved until about 34 weeks of pregnancy, the complications will be significantly reduced even if the fetus is born prematurely, and the survival rate of the fetus will be significantly increased, and the complications in the postpartum period will also be reduced. Therefore, for women with cervical insufficiency, cervical cerclage is the preferred treatment for fetal preservation.