Cervical Insufficiency

Cervical insufficiency is a condition that can cause second trimester pregnancy loss or preterm delivery of an extremely premature baby. It occurs when the cervix dilates in a woman who is not in active labor.  Cervical insufficiency can be treated by an operation called cervical cerclage, during which a suture is used to close a dilated cervix.

Cervical insufficiency has been a long-standing interest of Dr. Avick Mitra, director at WakeMed Physician Practices (WPP) – Maternal-Fetal Medicine. He has over 25 years of experience in caring for women with this condition and helping them find hope for having the baby they have always dreamed of having.

“Cervical insufficiency is a treatable condition,” explained Dr. Mitra. “There is never a guarantee, but with a thorough evaluation and appropriate surgery, women who are suffering from cervical insufficiency have an 85 to 90 percent chance of a successful pregnancy that ends when they take home their healthy baby.”

Signs & Symptoms
Often, cervical insufficiency presents no symptoms. However, sometimes subtle indicators can occur, such as increased or mucous vaginal discharge, vaginal spotting or bleeding, increased pelvic pressure, and regular uterine cramps or mild contractions. Because symptoms are subtle or even absent, cervical insufficiency is difficult to diagnose during a woman’s first pregnancy. Sometimes, cervical insufficiency is discovered when a woman goes to the doctor for a routine second trimester ultrasound, and the ultrasound reveals that her cervix is dilated one to two centimeters. Most often, women are unaware that there is a problem at the time of the ultrasound.

Obstetric history can be a very important indicator of cervical insufficiency. Any woman who has suffered from one or more pregnancy losses at 16 to 26 weeks should consult with a maternal-fetal medicine specialist either before getting pregnant again or in the first trimester of the next pregnancy.  Cervical insufficiency is not the cause for all second trimester pregnancy losses. Therefore, a specialist can evaluate a woman’s condition and establish an appropriate plan for the management of her pregnancy. Unfortunately, there are no diagnostic tests that can establish whether a past loss was definitively due to cervical insufficiency.

Risk Factors
The cause of cervical insufficiency is mostly unknown. While women with a history of cervical operations, such as cold knife conization of the cervix or the loop electrosurgical excision procedure (LEEP), have a mildly increased risk for cervical insufficiency, most women with cervical insufficiency have no identifiable risk factors. The majority of women are born with it, and it does not typically affect other family members (there is no strong genetic connection). The most important indicators for cervical insufficiency are a prior 16 to 26 week loss or preterm delivery.

While some women with cervical insufficiency are admitted to the hospital for expected management (rest and observation), the only true treatment for severe cervical insufficiency is cerclage. Transvaginal cerclage is a surgery during which a suture essentially ties and closes the cervix (or keeps the cervix closed in the case of preventative cerclage) in the hopes that a woman can continue her pregnancy to term or near term. While the risks for early, preterm delivery are still present, Dr. Mitra’s personal success rate with the transvaginal cerclage is approximately 90 percent, with the average patient delivering at 33 to 34 weeks of pregnancy.

There are three different circumstances for placement of a transvaginal cerclage:

  • History-Indicated Cerclage: When a woman has a history of one or more pregnancy losses at 16 to 26 weeks, the cerclage procedure can be performed at 12 to 16 weeks as a preventive measure, if the losses were determined to be from cervical insufficency.
  • History- and Ultrasound-Indicated Cerclage: When a woman has a concerning history but it is not definitive, she may be followed closely by doctors during her second trimester via serial cervical surveillance (ultrasound and speculum exam). If there is enough of a change in the length and shape of her cervix during this surveillance, the cerclage procedure can be performed.
  • Exam-Indicated Cerclage: This type of cerclage is an emergency procedure that is performed when a woman is found to have a dilated cervix but is not actively laboring or showing signs of intrauterine infection. Cerclage cannot be performed under these conditions.

After receiving a transvaginal cerclage, a woman will often not need to restrict her activity level. However, under some circumstances (exam-indicated cerclage), a patient may be asked to modify her activity level and take it easy for a few weeks. Typically, she will be able to return to her normal activities at 26 weeks of pregnancy.

The transabdominal cerclage (TAC) is another option reserved for women with the severest cases of cervical insufficiency. Indications for TAC include either:

  • A history of prior failed transvaginal cerclage
  • Cervical anatomy that makes it surgically impossible to place an effective transvaginal cerclage

For TAC, a cerclage is placed around the cervix by going in through the abdomen instead of the vagina. This procedure is preferably performed on non-pregnant women but it can also be placed at 10 to 14 weeks of pregnancy (during pregnancy, there is a small chance of perioperative pregnancy loss). Once a TAC is in place, cesarean delivery is required for all subsequent pregnancies. After a transvaginal cerclage, a woman can still give birth vaginally.

Cerclage at WPP-Maternal-Fetal Medicine
With years of experience in both transvaginal and transabdominal cerclage, Dr. Mitra will consider placing a cerclage (especially emergency, exam-indicated cerclage) on some patients who are not regarded by others to be candidates for the procedure. This includes patients who are at the borders of fetal viability (23 to 25 weeks pregnant) and women who are pregnant with twins. 

“I am fully aware of the prevailing expert opinions,” explained Dr. Mitra. “However, after a thorough preoperative evaluation and extensive counseling about the option of expectant management (bed rest, usually in the hospital until delivery), I will sometimes perform a cerclage procedure, if circumstances are appropriate, on a woman who is up to 26 weeks pregnant or on a woman who is pregnant with twins. I have personal outcome data that indicate successful outcomes under these circumstances are possible. Of course, success under these high-risk circumstances can never be guaranteed.”

Dr. Mitra’s colleagues at WakeMed Physician Practices – Maternal-Fetal Medicine are part of his team of specialists who can consult and treat women with cervical insufficiency. WakeMed Physician Practices - Maternal-Fetal Medicine is located on the WakeMed Raleigh Campus, in Holly Springs and at the WakeMed North Hospital, home of the WakeMed North Family Health & Women’s Hospital. For an appointment, please ask your obstetrician to call for a consultation: 919-350-6002.