Placental coverage of the endocervical os means that the placenta reaches or completely covers the endocervical os, which is diagnosed as placenta praevia before 28 weeks of gestation and placenta previa before 28 weeks of gestation. Before 28 weeks of pregnancy, the placenta covering the cervical opening is called placenta praevia, and after 28 weeks of pregnancy, the placenta covering the cervical opening is called placenta praevia. Depending on the degree of coverage, it is classified as complete placenta praevia, partial placenta praevia, or borderline placenta praevia, which may result in painless vaginal bleeding in the late stages of pregnancy, and may easily lead to preterm labor or hemorrhagic anemia. When a pregnant woman performs an ultrasound and finds that she has a placenta covering the endocervix, she needs to seek medical treatment promptly to prevent pregnancy accidents. Usually pay attention to adequate rest, reduce the greater emotional stimulation, is conducive to maintaining the stable growth and development of the fetus in the uterus, pregnancy needs to be regular pregnancy checkups in order to detect problems as early as possible.