A U-shaped opening in the endocervix indicates a loose cervix, which usually does not close naturally before delivery. In the absence of a full-term pregnancy, the presence of a U-shaped opening indicates a loose cervical opening. With the prolongation of pregnancy, the uterine pressure on the cervical opening will gradually increase, and the cervical opening may become larger and larger, so it is unlikely to close naturally before delivery, and it can be treated with cervical cerclage, if necessary. It is recommended that once a patient finds out that she has a U-shaped cervical opening, she should not be too anxious, avoid heavy physical labor, ensure adequate nutrition, and consult a doctor in time to complete the relevant examinations and then carry out standardized treatment.