Approximately 10% of pregnancies nowadays ends in premature delivery. There is 3.3 times more possibility for a pregnant woman to undergo premature labor if she has an incompetent cervix (Source) A narrow neck-like passage that forms the uterus’s lower part and extends to the vagina is called the cervix. If a pregnant woman’s cervix is weak, it starts to widen and thins out before the pregnancy reaches full term, unlike the dilation and effacement that occurs in response to uterine contractions in a normal pregnancy. Therefore, a weak cervix can cause pregnancy loss or can lead to preterm birth. Cervical cerclage is the procedure that helps to prevent the consequences due to cervical weakness. Here is all that you need to know about this procedure.

What Causes Incompetent Cervix?

A weakened or incompetent cervix can be caused by any of the following conditions:

• Previous surgery on the cervix
• Abnormalities of cervix or uterus from a birth defect
• Previous trauma to the cervix, such as a D&C and abortion during the second trimester
• A wrongly conducted abortion can damage the cervix permanently

What Is Cervical Cerclage?

It is a small surgical procedure in which a suture is placed around the incompetent cervix during pregnancy to prevent it from opening due to any pressure as the pregnancy progresses. Most often, the women who need a cervical cerclage in one pregnancy will require it in successive pregnancies.

Wh at Are The Types Of Cervical Cerclage?

There are basically 3 types of cervical cerclage. These are:

1. McDonald cerclage: During this procedure a thick band (5 mm) of permanent stature is placed on the upper part of cervix while there is effacement in the lower part of the cervix McDonald cerclage is generally placed between the 16th to 18th weeks of gestation and is removed at the 37th week of pregnancy. This procedure is not known to cause any hindrance with vaginal delivery
2. Shirodkar cerclage: This procedure is similar to McDonald cerclage but here the stitch pass through the cervix wall so they are not uncovered. This is not a very common procedure and is more difficult to perform than McDonald cerclage but it is known to reduce any kind of infection risk. Shirodkar cerclage sometimes involves the use of permanent stitch to tie the cervix and is left on for a lifetime. Here a C-section delivery becomes imperative
3. Trans abdominal cerclage: This is the most uncommon type of cerclage and is permanent in nature. In this procedure, a band is placed at the very top and outside of cervix, inside the abdomen. It is performed when the cervix is very short to perform other types of cerclage or there is a failure of vaginal cerclage. Since this is a permanent procedure, a C-section is required for childbirth

When Can A Cerclage Be Placed?

Usually, cervical weakness will be detected during the routine tests conducted in the first trimester itself. The most appropriate time for the cervical cerclage procedure is during the 3rd month, usually between the 12th and 14th weeks of gestation (elective cerclage). There may be cases where some pregnant women may develop cervical weakness during later stages of pregnancy. They will require a cervical cerclage which is known as an emergent cerclage and the procedure is performed after the cervix has already started to open up.

What Are The Benefits Of Cervical Cerclage?

• Helps prevent miscarriage
• Helps prevent premature labour due to incompetent cervix
• Has a high success rate especially when done earlier in the pregnancy
• Highly effective when cervical incompetence exists during pregnancy

What Happens During The Cervical Cerclage Procedure?

The doctor administers general, spinal or epidural anesthesia to the pregnant women to manage the pain during the procedure. The doctor will stitch a band consisting of strong thread around the cervix. This thread will be tightened to firmly close and hold the cervix together.

What Can I Expect After The Procedure?

• After the procedure, the pregnant woman will be kept under observation either for few hours or overnight in the hospital to look for any symptoms of preterm labor
• The pregnant woman might be advised bed rest and avoid any kind of physical activity for couple of weeks
• A regular follow-up is necessary with the doctor to monitor the stitch and look for any signs of premature labor
• Doctor will prescribe medicine to avoid any kind of infection or preterm labor
• Immediately after the procedure, a pregnant woman might notice light bleeding and experience mild cramping which is normal and should go away in few days. A pregnant woman will also notice thick vaginal discharge which will continue until the end of the pregnancy

How Long Is The Cerclage Stitch Left In?

Generally, the cervical cerclage is removed at the 37th week of pregnancy. But it can be removed earlier if the water breaks or if the pregnant woman experiences contractions.

Is Cervical Cerclage A Risk-Free Procedure?

Unfortunately, cervical cerclage is not a hundred percent risk-free procedure. Cervical cerclage can set forth a chain of issues that could end in spontaneous abortion or premature labor.

What Are The Risks Associated With A Cervical Cerclage?

Cervical cerclage is a life-saving procedure. Therefore, the necessity outweighs the possible risks involved in this procedure. After the cervical cerclage, about 1-9 % of pregnant women are found to undergo premature delivery. Here are 8 possible risks associated with cervical cerclage:

1. Infection: Chorioamnionitis, the amniotic sac infection, and the infection of the cervix can happen due to cervical cerclage. Specifically, if the cervical cerclage is conducted during the second trimester, the chances of chorioamnionitis is doubled. Some pregnant women also experienced yeast infection after cervical cerclage
2. Premature contraction: If the infection is spread to upper genital tract, it can set off preterm contractions, which end in preterm labor
3. Cervical dystocia: Cervical dystocia refers to the mechanical obstruction of the cervix. The cervix cannot dilate normally as the labor progresses thereby complicating the labor. Cervical cerclage can cause cervical dystocia thereby necessitating a C- section
4. Cervical laceration: If the women get into the labor before removing cervical cerclage, cervical laceration (tearing of the cervix) can happen which increases the chances of excessive bleeding
5. Chances of bladder injury: Sometimes the strong pressure is applied to the cerclage to remove it if it is covered by tissue. Trying to remove the cervical cerclage like this can result in bladder injury. Though this is a rare occurrence
6. Premature and preterm rupture of membrane: Premature breakage of amniotic sac can happen due to cervical cerclage
7. Cervical stenosis: This condition refers to permanent narrowing and closure of the cervix. This can happen as an after effect of cervical cerclage
8. Increase the chances of miscarriage: Infection and other complication that is associated with cervical cerclage can increase the chances of miscarriage

In addition to the above risks, all the risk that associated with local or general anesthesia is relevant to this surgical procedure too.

What Is The Success Rate Of Cervical Cerclage?

A cerclage is considered successful if the patient could able to hold the pregnancy for a full term, that is, for 37 weeks. The success rate of this procedure is about 80–90% in case of elective cerclage, and the success rate is about 40–60% for emergent cerclage (Source)

What Are Alternatives To The Cervical Cerclage Procedure?

Usually, bed rest is the most appropriate alternative to cervical cerclage. It is usually advised to those pregnant women in whom the changes in the cervix are found very late in pregnancy or in cases where cervix has already opened up significantly.