Did you know?

The first successful cervical cerclage was reported by Shirodkar in 1955. However, because this procedure often resulted in significant blood loss and the sutures were difficult to remove, doctors searched for alternative methods.

The McDonald cerclage, introduced in 1957, had success rates comparable to the Shirodkar procedure-and also minimized the amount of cutting and blood loss, the length of surgery, and the difficulty in removing the sutures. For these reasons, many doctors prefer the McDonald method. Others use a modified Shirodkar approach, which is easier and safer than the original technique.

If your care provider suspects that you have an insufficient cervix, he or she may recommend reinforcement of the cervix with use of a procedure called cervical cerclage. Before the cervix is surgically reinforced the doctor will check for fetal abnormalities by performing an ultrasound.

How Is a Cerclage Performed?

A cerclage is performed in an operating room, with the patient under anesthesia. The doctor approaches the cervix through the vagina. A band of sutures (stitches, thread or like material) is sewn around the cervix to keep it closed. The suture is placed close to the internal os (the end of the cervix that opens into the uterus).

A transabdominal cerclage is a special type of cerclage requiring an incision in the abdominal wall. This technique may be used when there's not enough cervical tissue to hold the suture or when a previously placed cerclage was unsuccessful. For a woman with a history of multiple pregnancy losses, a doctor may place an abdominal cerclage before pregnancy.

When Is a Cerclage Performed?

Most cerclages are performed during the second trimester of pregnancy (between 13 and 26 weeks of pregnancy), but they can be placed at other times as well, depending on the reason for the cerclage. For example:

  • Elective cerclages are usually placed around the 15th week of pregnancy, usually because of complications during a past pregnancy.
  • Urgent cerclages are placed when an ultrasound exam shows a short, dilated cervix.
  • Emergency or ?heroic? cerclages are usually placed between the 16th and 24th week of pregnancy if the cervix is dilated more than 2 cm and already effaced, or if the membranes (bag of waters) can be seen in the vagina at the external os (the cervical opening in the vagina).

What Are the Potential Complications?

Elective cerclages are relatively safe. Urgent or emergency cerclages have a higher risk of complications, including rupture of the membranes surrounding the baby, uterine contractions, and infection inside the uterus. If infection occurs, the suture is removed and labor is induced to deliver the baby immediately. For mothers who undergo an emergency cerclage, there is also the risk that the procedure will only prolong the pregnancy to 23 or 24 weeks. At this age, babies have a very high risk of long-term problems.

Studies have shown that women who require a cervical cerclage are at an increased risk for preterm labor and generally require more hospitalization during their pregnancies.

What Happens Afterwards?

Placing the cerclage is just the first in a series of steps that may be necessary to ensure the success of the procedure and your pregnancy. After the operation, your doctor may prescribe medication to stop your uterus from contracting. You may take this medicine for a day or two. After discharge from the hospital, your doctor will want to see you regularly to assess for preterm labor.

Infection is a concern after any surgical procedure. If you've had an urgent or heroic cerclage, the risk of infection is increased. This is because the vagina contains bacteria that are not found inside the uterus. When the bag of waters hangs down into the vagina, there is an increased risk of bacterial infection inside the uterus and within the amniotic sac holding the baby. Your doctor may prescribe antibiotics to reduce the risk of infection. If an infection is found within the bag of waters, the pregnancy should be terminated in order to prevent serious health consequences to the mother.

The suture is generally removed around the 35th to 37th week of pregnancy, when the baby has reached full term. An abdominal cerclage cannot be removed, and women who have abdominal cerclages will need C-sections to deliver.

What Happens Afterwards?

Placing the cerclage is just the first in a series of steps that may be necessary to ensure the success of the procedure and your pregnancy. After the operation, your doctor may prescribe medication to stop your uterus from contracting. You may take this medicine for a day or two. After discharge from the hospital, your doctor will want to see you regularly to assess for preterm labor.

Infection is a concern after any surgical procedure. If you've had an urgent or heroic cerclage, the risk of infection is increased. This is because the vagina contains bacteria that are not found inside the uterus. When the bag of waters hangs down into the vagina, there is an increased risk of bacterial infection inside the uterus and within the amniotic sac holding the baby. Your doctor may prescribe antibiotics to reduce the risk of infection. If an infection is found within the bag of waters, the pregnancy should be terminated in order to prevent serious health consequences to the mother.

The suture is generally removed around the 35th to 37th week of pregnancy, when the baby has reached full term. An abdominal cerclage cannot be removed, and women who have abdominal cerclages will need C-sections to deliver.

How Successful Is Cerclage?

No single treatment or combination of procedures for an insufficient cervix can guarantee a successful pregnancy. The most that doctors can do is minimize the risk to you and your baby. As a general rule, cerclages work best when they are placed early in pregnancy and when the cervix is longer and thicker.

Rates for carrying the pregnancy to term after cerclage vary from 85 to 90 percent, depending on the type of cerclage used. (Success rates are calculated by comparing the number of pregnancies delivered at or close to term with the total number of procedures performed.) In general, elective cerclage has the highest success rate, emergency cerclage has the lowest, and urgent cerclage falls somewhere in between. The transabdominal cerclage is rarely performed and an overall success rate has not been calculated.

While a number of studies have shown good results after cerclage, no high quality study has shown that women who undergo cerclage have significantly better outcomes that those who go on bed rest.