Mitigating the Risks of Cervical Insufficiency

By Cole Douglas Greves, MD, FACOG

As an OB-GYN, I have a tremendous respect for the intricacies of pregnancy and childbirth.

Having a baby can be one of the most amazing and joyous experiences. But for some, it can be a difficult and anxious time. As part of a Maternal-Fetal Medicine group, I am able to help guide women and families through the stress and uncertainties of a high-risk pregnancy — understanding each woman’s unique challenges and providing the appropriate treatment at every step along the way. I also value the partnership with a woman’s primary OB-GYN, with a shared goal of a safe pregnancy and delivery, and a healthy mother and baby.

Affecting about 1 in 100 pregnancies, cervical insufficiency is defined as painless, cervical dilation in the absence of persistent uterine contractions. During pregnancy, the cervix, which is the opening of the uterus into the vagina, normally stays firm and closed until late in the third trimester. In preparation for the baby’s birth, the cervix becomes thinner and softer, shortens and dilates, creating the birth canal for the baby to pass through during delivery. Cervical insufficiency, also known as incompetent cervix, is a condition that occurs when these changes take place too early in the pregnancy. Cervical insufficiency can put expectant mothers at higher risk for pregnancy loss or premature birth.

Because these changes are usually painless, cervical insufficiency often isn’t detected until it’s too late — when it is seen on an ultrasound or when a woman experiences downward pressure in the pelvis that signals dilation and positioning of the fetus into the birth canal. Almost 25 percent of miscarriages in the second trimester are due to cervical insufficiency.

The good news is that there are treatment options available that can help prolong the pregnancy of a woman with cervical insufficiency, ideally to full term. With cerclage, a procedure that can help prevent the cervix from opening too soon, we can mitigate the risks of cervical insufficiency and hopefully keep the baby in place as long as necessary.

Causes Of Cervical Insufficiency

Since there usually is not a definitive cause and effect relationship, it’s difficult to predict who will experience cervical insufficiency. Factors that may cause the condition include:

• Biological makeup and how the cervix interacts with the hormones produced during pregnancy.

• Past cervical trauma, including injury or past cervical surgery, such as surgeries to remove pre-cancerous or cancerous cells. This has become somewhat less common in recent years, as many women are now vaccinated against the human papillomavirus (HPV) that is linked to cervical cancer.

• Genetics also may play a role. If a close family member has had cervical insufficiency, preventive measures may be advised.

The model scenario for diagnosing cervical insufficiency is to spot signs of early cervical change during the mid-pregnancy ultrasound that usually takes place at 18-20 weeks. If cervical insufficiency is suspected, a follow-up transvaginal ultrasound can provide an accurate evaluation of the cervix and its length. Based on what is seen on the ultrasound or if there is a history of cervical insufficiency, a decision will be made either to monitor the situation or move forward with treatment.

Treatment Options For Cervical Insufficiency

Depending on how advanced the cervical insufficiency is, the recommended first option, particularly for a first pregnancy, could be progesterone vaginal suppositories. Progesterone is a hormone that can help stabilize the structure of the cervix and reduce inflammation, potentially preventing cervical insufficiency from progressing.

If progesterone treatment fails, the next step may be transvaginal cervical or abdominal cerclage. Cerclage is a treatment option for cervical insufficiency that can help prevent the cervix from opening too soon. The Center for Maternal-Fetal Medicine at Orlando Health Winnie Palmer Hospital for Women & Babies provides expertise in all types of cerclages and is one of few in Florida to offer transabdominal cerclage.

In a transvaginal cerclage, the weakened cervix is stitched shut and/or reinforced through the opening to the vagina. Usually performed during the 12th to 14th week of pregnancy, a transvaginal cerclage is the preferred method, if possible, since it is less invasive with no abdominal surgical incision needed. A transvaginal cerclage stitch is typically removed around 37 weeks of pregnancy in anticipation of a vaginal delivery.

A transabdominal cerclage is a surgical procedure in which the cervix is accessed through an incision in the lower abdomen. The cervix is then encircled with a stitch to reinforce it and help ensure that it remains closed during the pregnancy. For women who have no cervix or a history of incompetent cervix with previous unsuccessful vaginal cerclage placement, including those who have experienced pregnancy loss, this procedure can be performed prior to pregnancy. If performed during pregnancy, transabdominal cerclage placement will typically be done between the 9th and 14th week. Transabdominal cerclages require a Cesarean section delivery for every pregnancy going forward and are normally kept in place until a woman reaches the end of her childbearing years.

Cerclage can be very effective at helping women with cervical insufficiency maintain or prolong their pregnancies. With regular monitoring throughout the duration of the pregnancy, we can help ensure a successful progression, safe delivery, and healthy mom and baby.

Cole Douglas Greves, MD, FACOG, a board-certified clinical perinatologist, is director of the Fetal Care Center, part of the Center for Maternal-Fetal Medicine at Orlando Health Winnie Palmer Hospital for Women & Babies. Dr. Greves has more than 15 years of experience with cerclage procedures — including those placed transabdominally –which is available at only a handful of hospitals. He also has conducted extensive research in other areas and is a fre- quent presenter at medical conferences and meetings. After earning his medical degree from the University of North Dakota School of Medicine in Grand Forks, Dr. Greves completed his OB-GYN residency at Orlando Health and a fellowship in Maternal-Fetal Medicine at the University of Rochester – Strong Memorial Hospital in Rochester, New York. 

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