Pregnant women who have "cervical insufficiency" tend to have a premature birth or miscarriage. An improvement on an old procedure might help.
For Angela Norton, the news of a second pregnancy brought both joy and anxiety because her firstborn, Kayla, was premature and weighed just 1.5 pounds at birth.
Angela says, "I had gone to my doctor when I was pregnant with Kayla and he had told me at four months I’d need a cerclage.”
Angela had an insufficient cervix, too weak to support a baby. In a cerclage, doctors stitch up the bottom tip of the cervix to strengthen it.
Dr. Abdulla Al-Khan says, "You’re just taking a string, like a shoelace and you’re just putting it all around the cervix and just tying it in the front.”
Angela's first cerclage was done through the traditional route, vaginally. Because it failed, doctors did the cerclage for her next pregnancy through her abdomen.
Dr. Al-Khan says, "The rationale for abdominal cerclage is placement of the suture. It’s as high as possible. Because putting the stitch at the tip of the cervix may not really do the job. If you want to do it, you need to do it right at the base.”
The procedure can be done with traditional open surgery or laparoscopically, through four small incisions.
Dr. Al-Khan says, "If you do the laparoscopic route, it can be a little longer. So you’re exposing the patient to long anesthesia, but also it’s minimally invasive.”
This time, Angela’s pregnancy was closer to full term. Baby Nathaniel weighed a healthy six pounds.
Angela says, "To have Nathaniel at the month that I did, it was -- it was wonderful.”
Women who have the abdominal cerclage deliver by caesarean section. If they want to have more children, the cerclage sutures stay in place. If not, they're removed. A cerclage is typically placed near the end of the first trimester.
Fast Facts:About 12.3 percent of babies in the U.S. are born prematurely.
Cervical insufficiency, or the inability of the cervix to support and retain the growing fetus, can lead to premature labor. The condition occurs in about one percent of all pregnancies.
A procedure called cerclage is used to reduce the risk of premature birth from cervical insufficiency by tying a suture around the cervix. Cerclage is traditionally performed through the vagina.
Some doctors are now performing cerclage through tiny incisions made in the abdomen. The trans-abdominal approach offers a more secure fix because it provides a tight stitch at the top of the cervix, rather than at the bottom.
A normal pregnancy lasts about 40 weeks. Preterm birth is the delivery of a baby before 37 weeks of pregnancy. Data collected from the U.S. Department of Health and Human Services shows preterm deliveries accounted for 12.3 percent of all births in 2003.
When a baby is born early, the infant’s organs and body systems may not be fully developed. They may have underdeveloped lungs and breathing difficulty. Some may require a respirator to help them breathe. Preterm babies are at risk for bleeding in the brain (intraventricular hemorrhage), a condition that can lead to brain damage. These tiny babies are also at risk for infections, retinopathy (a problem affecting the blood vessels in the eyes, causing vision loss), anemia, feeding problems and trouble regulating body temperature.
The cervix is a muscular canal at the lower end of the uterus. It connects the uterus to the vagina. During pregnancy, the cervix remains closed and holds the fetus inside the uterus. At the end of pregnancy, the cervix begins to thin. As the birth approaches, the cervix begins to stretch and dilate, opening to allow the passage of the fetus into the birth canal.
Cervical insufficiency is the inability of the cervix to support and retain a fetus in the uterus. As the fetus grows, the cervix thins and dilates, causing the membranes to slip through the cervix into the vagina. The membranes rupture and the fetus falls into the birth canal. The birth occurs involuntarily without any signs of contractions – usually in the second trimester or early part of the third trimester.
Research suggests about one percent of all pregnant women have cervical insufficiency. Surgery or trauma to the cervix are risk factors for cervical insufficiency.
Cerclage for Cervical Insufficiency
Cerclage is a procedure to temporarily strengthen the cervix. The procedure is traditionally done through the vagina. Once the cervix is clearly identified, a suture (strong thread) is placed around the cervix and tightened. The suture firmly closes the cervix, and hopefully, prevents the membranes and fetus from slipping into the birth canal.
Some doctors are now performing cerclage through the abdomen. Abdulla Al-Khan, M.D.,OB/GYN at Hackensack University Medical Center, says the transabdominal approach is done through four small incisions – one below the belly button, one on each side, and one just over the bladder. Using viewing scopes for guidance, the cervix is located. The suture is passed around the top of the cervix and tightened.
Al-Khan says the transabdominal approach may provide more support than a vaginally placed cerclage. That’s because going through the abdomen allows doctors to gain access the top of the cervix. When the stitch is placed through the vagina, the closure is at the lower end of the cervix, allowing the weight of the fetus to push on the upper cervix.
Transabdominal cerclage is best done between the 9th and 12th weeks of pregnancy. If done later in the pregnancy, it becomes more difficult for the physician to visualize and avoid vital structures, like the ureters and major blood vessels.
Cerclage prevents the cervix from opening. Research suggests the procedure is 85 to 90 percent successful in preventing preterm birth. In most cases, women who have had a transabdominal cerclage are scheduled for C-section around the 37th week of the pregnancy. (C-section will also be performed if the woman goes into preterm labor.) The stitch can be removed after the baby is delivered. If the woman wants to have more children, doctors may leave the stitch in place. Vaginal birth after cerclage is possible, but the suture must be removed to allow the cervix to open and the baby to pass into the birth canal.
The use of cerclage must be done with careful consideration. There are no clear-cut definitions of who should have the procedure. Cerclage can cause premature contractions, rupture of the membranes, infection, tearing of the cervix and problems with cervical dilation. The American College of Obstetricians and Gynecologists says the benefit of cerclage for women at low to medium risk of second-trimester pregnancy loss has not yet been proven.
Web Resources:American Pregnancy Association Web site
For information on preterm birth or cervical cerclage:
March of Dimes Web site