What is cervical insufficiency? It is the painless dilatation of the cervix in the middle of pregnancy that eventually leads to miscarriage, and in some cases, to preterm labor. Other factors such as infection, bleeding, placental abruption, etc. need to be ruled out for late miscarriage. Risk factors for cervical insufficiency include intrauterine estrogen exposure (which is very rare in our country); abnormal uterine development that predisposes to cervical insufficiency; polycystic ovary PCOS; multiple dilation, uterine evacuation, birth trauma, cervical laceration, post-cervical conization, etc. that predispose to cervical insufficiency. Lack of objective gold standard for diagnosis The classical textbook diagnosis is the unresisted passage of the cervical 8-dilator rod during non-pregnancy. However, foreign studies have shown that this is not the gold standard for diagnosis, as it has been found that many menstruating women can pass a No. 7 or No. 8 dilator rod without resistance during non-pregnancy, so it is not the gold standard by international standards. Other tests, such as iodine oil hysterosalpingography and endocervical resistance measurement, do not allow a definitive determination of full cervical function during non-pregnancy. At present, the diagnosis of cervical function is mainly a clinical diagnosis, but there is no objective gold standard. Cervical function is not a concept of “complete” or “absent”, but varies in degree, manifesting itself in different conditions of miscarriage, as well as in some influencing factors such as insidious vaginitis, intrauterine infection, strain, multiple births, etc., which may induce cervical insufficiency and aggravate its manifestation. However, there is a lack of objective means of diagnosis and ultrasound can help us to determine and understand the condition of cervical function. In a typical ultrasound presentation of cervical insufficiency, the anterior and posterior lips of the cervix are not actually shortened, and later contractions can be accompanied by shortening of the cervix. Treatment options Conservative methods, mainly activity restriction and bed rest, are available. There are also newer methods such as cervical braces, but the clinical efficacy is not clear. Surgical treatment with annuloplasty: there are two approaches: transvaginal and transabdominal, commonly used are transvaginal MacDonald and Shirodkar, both of which have been used clinically since the 1960s and have been found to have similar efficacy in the treatment of cervical insufficiency. The transabdominal approach is generally recommended after a failed transvaginal procedure, open or transabdominal, provided that delivery by cesarean section is performed. It is very difficult to manage if midtrimester induction of labor is required due to fetal factors. MacDonald procedure: transvaginal, without pushing up the bladder, simple operation and low risk of injury. The disadvantage is the low position of the ligature. Shirodkar’s procedure: the vaginal wall of the fornix needs to be incised and the bladder pushed upwards, the position is high and the loop is performed as close as possible to the level of the main ligament, the operation is relatively difficult, the risk of bleeding and injury is high and anesthesia is needed to remove the loop. Because the results of both procedures are similar, it is preferred to do the MacDonald procedure. Indication and timing of annuloplasty Based on a typical history of more than 1 painless midtrimester abortion or a history of previous annuloplasty, other factors need to be excluded. –Prophylactic annuloplasty. No history of late miscarriage in mid-pregnancy, but clinical finding that the fetal sac has protruded into the vagina or that the internal and external cervical opening has dilated on ultrasound images, while excluding infection as a result. –Therapeutic IUD (emergency or rescue IUD). With a history of late miscarriage or preterm labor, this ultrasound monitoring of the cervical length with a significant shortening of the cervical canal of less than 25 mm, IUDs can significantly improve the preterm labor rate. Perioperative management The importance of screening for vaginitis is particularly emphasized in the preoperative preparation. Circumcision is mainly a matter of infection and it is very important to screen for infection. In case of emergency annuloplasty, individuals recommend not to perform it immediately, but to perform the procedure when the inflammation is drained and the culture of vaginal and cervical secretions is negative and there is no vaginitis or contractions. If there is an obvious infection, the procedure should be done with caution. Prophylactic IUDs may be considered for appropriate delay of the procedure if the placenta is in a low-set condition. Specifically on the question of whether to use contraction inhibitors in the perioperative period, the guidelines and the British guidelines suggest that they can be used without them, but in my own clinical practice, a little is applied prophylactically and not routinely. Antibiotics are also not recommended by either guideline and are applied for the presence of inflammation, at the discretion of the individual in clinical practice. Neither progesterone nor activity restriction is explicitly recommended. Special emphasis is placed on individualized management of cervical insufficiency, where infection prevention and informed patient consent are important. When to remove stitches, without abnormalities 36-37 weeks. Or if there are significant prodromal-like contractions, the stitches should be removed promptly to prevent cervical laceration. Cervical cerclage and premature rupture of membranes PPROM If premature rupture of membranes occurs after cerclage, it is recommended to remove the stitches promptly to abandon the fetus in the anovulatory stage. If it reaches the viable stage, it is recommended to consider removing the stitches after promoting fetal lung maturation, monitoring for infection, and applying antibiotics to prevent infection, as appropriate. This is because the main complication is the problem of infection. A history of 1 or more typical late miscarriages may be considered for circumcision, but is it always necessary? A British study showed that there was no significant difference in the rate of preterm birth before 33 weeks between those with a history of 1 late miscarriage and those without, and the same was true for 2. Only for those with a history of 3 or more, there was a significant difference between those with and without an IUD. Clinical practice still depends on the individual pregnant woman, and the doctor’s personal experience. Those who do not do it must be monitored closely by ultrasound for cervical length and if there are changes in the cervix. It was found that for those with a history of preterm labor or late miscarriage, routine monitoring of cervical length starting at 16 weeks of ultrasound can avoid about 50% of surgical interventions. Special reminder: cervical shortening is not the same as cervical insufficiency Cervical shortening can be due to insufficiency or other factors such as hyperinflation, inflammation, contractions, developmental problems, etc. It must be treated with caution and carefully analyzed. Those with cervical shortening alone, without a history of preterm birth, underwent annuloplasty and expectation, and the study found that annuloplasty did not significantly reduce the rate of preterm birth before 33 weeks. The analysis showed a significant increase in the preterm birth rate with different cervical length shortening, and in those without a history of preterm birth, ring ligation did not significantly reduce the incidence of preterm birth. However, in those with a history of preterm birth and late miscarriage, IUDs significantly reduced the incidence of preterm birth. Thus, cervical shortening in the absence of a history of preterm labor or complete miscarriage is not a definite indication for IUDs; a history of preterm labor or late miscarriage is an indication for IUDs; and cervical shortening alone in multiple pregnancies is not an indication for IUDs, and IUDs did not significantly reduce the incidence of preterm labor. Other non-indicated conditions, such as a history of cervical surgery, such as after LEEP surgery or biopsy, did not reduce the incidence of preterm birth by routine performing loop ligation. A history of multiple dilation and congenital developmental abnormalities are high-risk pregnancies for cervical insufficiency, and education on the prevention and control of preterm labor is recommended, as well as transvaginal ultrasound monitoring of the cervix, and surgery if significant cervical changes occur or if cervical insufficiency is identified. In conclusion, there is no objective gold standard for the clinical diagnosis of cervical insufficiency. Circumcision has some efficacy, but it is important to strictly control the indications for circumcision to reduce adverse outcomes. Clear indications are: 1 history of preterm labor or late miscarriage with shortened cervix, 2 clinical ultrasound suggesting an open internal and external cervical opening and visible amniotic sac. Vaginal surgery is preferred for annuloplasty. Attention to individualized management, informed consent of the pregnant woman, and clinical experience of the surgeon are very important.