Cervical cerclage refers to a variety of procedures that use sutures or synthetic tape to reinforce the cervix during pregnancy in women with a history of a short cervix. The cervix is the lower part of the uterus that opens to the vagina.
Cervical cerclage can be done through the vagina (transvaginal cervical cerclage) or, less commonly, through the abdomen (transabdominal cervical cerclage).
Your health care provider might recommend cervical cerclage if your cervix is at risk of opening before your baby is ready to be born or, in some cases, if your cervix begins to open too early. However, cervical cerclage isn’t appropriate for everyone. It can cause serious side effects and doesn’t always work. Some women who have a cerclage placed for a short cervix might experience preterm labour. Understand the risks of cervical cerclage and whether the procedure might benefit you and your baby.
Why it's done
Before pregnancy, the cervix is closed, long and firm. During pregnancy, the cervix gradually softens, decreases in length (effaces) and opens (dilates) in preparation for birth. If you have an incompetent or short cervix, however, your cervix might begin to open too soon. As a result, you could experience pregnancy loss or give birth prematurely.
Your health care provider might recommend cervical cerclage during pregnancy to prevent premature birth if you have:
- A history of second trimester pregnancy loss related to painless cervical dilation in the absence of labour or placental abruption (history-indicated cervical cerclage)
- Prior cerclage due to painless cervical dilation in the second trimester
- Painless cervical dilation diagnosed during the second trimester
- A short cervical length (less than 25 millimetres) before 24 weeks of pregnancy, in a singleton pregnancy
Cervical cerclage isn’t appropriate for everyone at risk of premature birth. Your health care provider might not recommend a cervical cerclage if you have:
- Active vaginal bleeding
- Active preterm labour
- An intrauterine infection
- Preterm premature rupture of membranes — when the fluid-filled membrane that surrounds and cushions the baby during pregnancy (amniotic sac) leaks or breaks before week 37 of pregnancy
- Twin or higher order pregnancy
- A foetal anomaly incompatible with life
- Prolapsed foetal membranes — a condition in which the amniotic sac protrudes through the opening of the cervix
Risks associated with cervical cerclage include:
- Inflammation of the foetal membranes due to a bacterial infection
- Vaginal bleeding
- A tear in the cervix (cervical laceration)
- Preterm premature rupture of the membranes — when the fluid-filled membrane that surrounds and cushions the baby during pregnancy (amniotic sac) leaks or breaks before week 37 of pregnancy
- Suture displacement
After receiving a cervical cerclage, contact your health care provider immediately if you have leakage of fluid from your vagina, a sign of preterm premature rupture of membranes. Your health care provider will recommend removing the cervical cerclage early if you have preterm premature rupture of membranes or if you have symptoms that suggest a uterine infection.
How you prepare
Before cervical cerclage, your health care provider will do an ultrasound to check your baby’s vital signs and rule out any major birth defects. Your health care provider might take a swab of your cervical secretions or do amniocentesis — a procedure in which a sample of amniotic fluid is removed from the uterus — to check for infection. If you have an infection, a cerclage won’t be placed.
Ideally, a history-indicated cervical cerclage is done between weeks 12 and 14 of pregnancy. However, cervical cerclage can be done up until week 23 of pregnancy if a pelvic exam or ultrasound shows that your cervix is beginning to open. Cervical cerclage is typically avoided after week 24 of pregnancy due to the risk of rupturing the amniotic sac and triggering premature birth.
What you can expect
Cervical cerclage is typically done as an outpatient procedure at a hospital or surgery centre under regional or general anaesthesia. Most cervical cerclage procedures are done through the vagina.
Cervical cerclage might be done through the abdomen if transvaginal cerclage is unsuccessful or anatomically difficult due to an extremely short, lacerated or scarred cervix.
During the procedure
During transvaginal cervical cerclage, your health care provider will insert a speculum into your vagina and grasp your cervix with ring forceps. He or she might use ultrasound for guidance. Your health care provider will likely use the McDonald operation or the Shirodkar operation. Data suggests no significant difference in outcomes between the two methods.
During the McDonald operation, your health care provider will use a needle to put stitches around the outside of your cervix. Next, he or she will tie the ends of the sutures to close your cervix.
During the Shirodkar operation, your health care provider will use ring forceps to pull your cervix toward him or her while pulling back the side walls of your vagina. Next, he or she will make small incisions in your cervix where it meets your vaginal tissue. Then, he or she will pass a needle with tape through the incisions and tie your cervix closed. Your health care provider might use stitches to reposition vaginal tissue affected by the incisions.
During transabdominal cervical cerclage, your health care provider will make an abdominal incision. He or she might elevate your uterus to gain better access to your cervix. Next, your health care provider will use a needle to place tape around the narrow passage connecting the lower part of your uterus to your cervix and tie your cervix closed. Then he or she will set your uterus back into place and close the incision. The procedure also can be done laparoscopically.
After the procedure
After cervical cerclage, your health care provider will do an ultrasound to check your baby’s well-being.
You might experience some spotting, cramps and painful urination for a few days. Acetaminophen (Tylenol, others) is recommended for pain or discomfort. If your health care provider used stitches to reposition vaginal tissue affected by incisions in your cervix, you might notice passage of the material in two to three weeks as the stitches dissolve.
If you had history-indicated cervical cerclage, you’ll likely be able to go home after you recover from the anaesthetic. As a precaution, your health care provider might recommend avoiding sex for a few weeks or more, depending on the reason for the cerclage.
If you had cervical cerclage because your cervix had already begun to open or an ultrasound showed that your cervix is short, you might need to remain in the hospital for observation. As a precaution, your health care provider might recommend limiting physical activity and sex until delivery.
Your health care provider will continue to monitor you closely for signs or symptoms of preterm labour.
Cervical cerclage removal
A transvaginal cervical cerclage is typically removed at around week 37 of pregnancy — or at the start of preterm labour.
A McDonald cerclage can usually be removed in a health care provider’s office without anaesthetic, while a Shirodkar cerclage might need to be removed in a hospital or surgery centre. After having a transvaginal cervical cerclage removed, you’ll typically be able to resume your usual activities as you wait for labour to begin naturally.
If you expect to have a C-section and plan to have children in the future, you might choose to leave a Shirodkar cerclage in place throughout your pregnancy and after the baby is born. However, it’s possible that the cerclage could affect your future fertility. Consult your health care provider about your options.
If you had a transabdominal cervical cerclage, you’ll need to have another abdominal incision to remove the cerclage. As a result, a C-section is typically recommended. Your baby will be delivered through an incision made above the cerclage. During the C-section, you can choose to have the cerclage removed or leave it in place for future pregnancies.
The effectiveness of cervical cerclage is a topic of debate.
Research suggests that cervical cerclage reduces the risk of premature birth in women with proven cervical insufficiency.
However, the timing of cervical cerclage can also affect the outcome. Emergency cervical cerclage done in the presence of advanced cervical change and prolapsed membranes has a poorer outcome.