Cervical insufficiency, also known as endocervical atresia and cervical laxity, refers to the inability of the cervix to maintain pregnancy to full term due to anatomical or functional defects in the absence of contractions. In general, the diagnosis can be made clearly based on the medical history, clinical manifestations and relevant clinical auxiliary examinations. 1. Judgment of cervical insufficiency 1. Judgment according to medical history A clear history of cervical injury or repeated spontaneous miscarriage in the middle of pregnancy, with miscarriage mostly occurring in the same gestational week, without obvious abdominal pain and contractions, and rapid progress of labor; 2. Judgment according to clinical manifestations If early painless dilatation of the cervix occurs in the middle or late pregnancy, accompanied by expansion of the gestational sac into the vagina, and physical examination reveals old lacerations of the cervix, short vaginal segment of the cervix, and dilatation of the uterine orifice, the diagnosis can be made. (1) cervical examination: during non-pregnancy cervical palpation, the isthmus of the cervix is short and flaccid, and a No. 8 Hegar dilator can be used to pass the endocervix without resistance, which is a simple method to diagnose cervical insufficiency; (2) ultrasonography: it is the most common and effective method to diagnose cervical insufficiency during pregnancy. (2) ultrasonography: it is the most common and effective method to diagnose cervical insufficiency in pregnancy. In mid-pregnancy, cervical insufficiency can be ruled out if the diameter of the endocervix is ≤19 mm, and the diagnosis can be confirmed if the diameter is ≥23 mm; (3) hysterosalpingogram: the width of the cervical canal at the level of the endocervix is >0.6 cm, and the angle of the lower uterine segment of the cervical canal disappears. Treatment of cervical insufficiency Once the diagnosis of cervical insufficiency is confirmed, active measures should be taken to treat it. Common treatment methods are as follows: 1, general treatment: such as the usual activities should be limited, avoid sexual intercourse, prolonged standing or lifting heavy objects, avoid increasing the pelvic pressure, prohibit smoking, and patients in the middle of pregnancy should be absolutely bed rest, fetal preservation treatment; 2, drug treatment: according to the time of pregnancy can be applied salbutamol, ampoule, detroterone, magnesium sulfate and other contraction inhibitors, or according to the condition of the use of glucocorticoids and 3.Surgical treatment: It is a more effective treatment, mainly transvaginal cervical cerclage and laparoscopic cervical cerclage, which is usually performed around the fourth month of pregnancy to strengthen the tension of the cervical canal as much as possible and prevent the extension of the lower uterus and the dilatation of the cervical opening.