Cerclage is one of the surgical procedures in gynecology and consists, in the broadest sense, of surgical closure of the cervix in cases of cervical insufficiency (insufficient closure of the cervix during pregnancy). The painless softening and shortening of an insufficient cervix (cervix) can lead to late abortion (late miscarriage) or preterm delivery without labor and thus unnoticed by the mother. Causes of cervical insufficiency include ascending infections, a genetically determined change in connective tissue, or premature cervical maturation due to hormonal imbalances. The tissue changes underlying cervical insufficiency have a complicating influence on the performance of a cerclage. There are several surgical procedures. These are selected according to the clinical situations:
- Prophylactic cerclage/early total cervical closure (FTMV) according to Saling – procedure performed in case of a stressed history (three or more late miscarriages as well as premature births due to cervical insufficiency) in the 13th-16th week of pregnancy.
- “Urgent cerclage” – Therapeutic cerclage – procedure performed when the cervix (cervix) is shortened from normal 40-50 mm to ≤ 25 mm.
- Emergency cerclage – therapeutic cerclage – procedure performed in case of premature opening of the cervix or prolapsed amniotic sac (prolapse of the amniotic sac from the cervix with the risk of premature rupture).
“Therapeutic cerclage” is used to prevent late miscarriage, for example, premature opening of the cervix or prolapse of the amniotic sac (prolapse of the amniotic sac). The “prophylactic cerclage” (FTMV) is controversial. It was shown that such an intervention did not provide any advantage over systematic vaginal sonographic monitoring of patients based on history alone. Overall, the performance of cerclage needs to be carefully considered, as the benefits both in therapeutic, but especially in prophylactic cerclage, are not clear. The FTMV procedure is discussed in a separate article.
Indications (areas of application)
Cerclage is indicated for:
- Amniotic sac prolapse
- Shortening of the cervix uteri (neck of the uterus)
- Premature opening of the cervix
Contraindications
- Bacterial vaginosis (inflammation of the vagina caused by bacteria, for example).
- Bleeding
- Missed Abortion – intrauterine fetal death (IUFT; death of the baby in utero without “giving birth”).
- V. a. Amniotic infection syndrome (English : amniotic infection syndrome, abbreviated: AIS) – intrauterine (“inside the uterus“) infection, i.e. endogenous, pre- and subpartum (occurring before or under/during birth) infection of the amniotic cavity and its fetus with the risk of sepsis (blood poisoning) for the child.
- Premature rupture of the membranes
- Cervicitis (inflammation of the cervix)
Before surgery
Before the operation, a detailed explanation must be given regarding the risks of the procedure. Among the most important contents are premature induction of labor due to manipulation, injury to the amniotic sac and increased risk of infection. The information also includes the prospects of success compared to the conservative approach (no surgery, but intensive monitoring). For planning the procedure, a vaginal sonography is performed beforehand (ultrasound examination by means of a transducer through the vagina/vagina), which serves to assess the condition of the cervix (cervix; length, width of the cervical canal, opening of the inner cervix?, funnel formation?). Furthermore, sonographic assessment of the pregnancy (fetometry/measurement of the fetus, i.e. the unborn child) is also performed. Prior to surgery, vaginal swabs (vaginal swabs) are taken for bacteriological or mycological examination to rule out infections, such as mycosis (fungal infection) or bacterial infection. In the event of a positive smear result, appropriate antifungal or antibiotic therapy is initiated according to the resistogram (taking antibiotic resistance into account). In case of negative smears, prophylactic antibiotic administration with amoxicillin (3 x 2 g/d i.v.) or cephalosporins (e. g.e.g., cefazolin 3 x 1.5 g/d i.v.). Furthermore, close monitoring of laboratory inflammatory parameters (e.g., CRP, C-reactive protein) is also performed. In case of emergency cerclage with labor, drug tocolysis (labor inhibition) is performed.
Surgical procedures
Cerclage can be performed under general anesthesia (“general anesthesia“) or spinal anesthesia (spinal form of regional anesthesia). During the procedure, the patient is in the lithotomy position: she lies on her back with her legs bent at the hip joint by 90°, with the knees bent and the lower legs resting on supports so that the legs are spread apart by about 50°-60°. After disinfection of the surgical area, the patient is covered with sterile drapes. With the help of specula (gynecological instrument; used to unfold the vagina, thus making the vaginal skin and the cervix visible and accessible) and organ grasping forceps, the surgeon exposes or straightens the cervix uteri. Two methods are available for performing cerclage:
- McDonald’s method – In the so-called “bloodless” McDonald’s method, a tobacco bag suture is placed through the cervix with a nonabsorbable (nondissolvable) suture. The surgeon starts at 12 o’clock and passes the suture through the tissue at 9 o’clock, 6 o’clock and 3 o’clock, then stitches out again at 12 o’clock. This suture is then united and pulled tightly closed, and the ends of the resulting tobacco bag suture are cut long to facilitate later removal. Finally, the vagina is disinfected with PVP iodine solution.
- Method according to Shirodkar – In the “bloody” method according to Shirodkar, the suture is passed directly under the vaginal skin enveloping the cervix. For this purpose, an approximately 2-3 cm split of the vaginal skin on the anterior and posterior cervical wall is necessary. This is also called anterior and posterior colpotomy (vaginal incision). The surgeon starts after pushing up the bladder through a speculum at 12 o’clock, i.e. the unabsorbable suture is inserted there and carried out at 6 o’clock (i.e. on the opposite side), the suture is passed once on the left side and once on the right side, so that a suture runs on both sides of the cervical opening. Then, the two ends of the suture brought out at 6 o’clock are knotted tightly and the anterior and posterior colpotomies are closed. Again, the suture ends are left long and the surgical area is disinfected with PVP iodine solution.
After surgery
Postoperatively, close monitoring of the condition of the pregnancy (sonography) and laboratory inflammatory values (eg, CRP, C-reactive protein) should be performed. The surgical area should be inspected in a controlling manner and the condition of the cervix uteri assessed by vaginal sonography. Antibiotic therapy is continued, and any tocolysis (labor inhibition) started should also be continued for a maximum of 48 hours postoperatively. Release of the cerclage is usually done after the completed 37th week of pregnancy. Reasons for early removal of the cerclage include refractory labor or colpitis or cervicitis.
Possible complications
- Triggering premature labor
- Amniotic infection syndrome, the rare consequence of which may be endotoxin shock (release of systemic substances that lead to circulatory collapse and organ failure) or sepsis (blood poisoning).
- Complication of anesthesia (anesthesia and anesthesia).
- Premature rupture of the membranes
- Vesicovaginal fistula – Non-pysiological connection between the vagina and urinary bladder as a result of surgical injury to tissue.
