Cervical insufficiency (CI) means that a woman's cervix opens too early, before the baby is full term. This condition is also called incompetent cervix. The cervix is the opening to the uterus that sits at the top of the vagina. When the cervix is healthy, it thins out and opens at the end of pregnancy when labor begins. The baby then moves through the cervix and birth canal (vagina) to be born.
With CI, the cervix opens without labor starting. Usually the woman has no symptoms. Few women know they have cervical insufficiency until they have a miscarriage
or premature birth
. The woman may give birth to the baby without feeling contractions
If you've had a pregnancy affected by CI, the condition is likely to happen again in later pregnancies.
Medical experts do not always know why incompetent cervix occurs. Theories include damage to the cervix during surgery, injury during a previous birth, and exposure to certain drugs
Cervical length appears to be a factor. The shorter the cervix, the more likely you are to have cervical insufficiency. Ask your health care provider
about having an ultrasound
to check for short cervix.
Providers have not found a reliable way to routinely check all women for cervical insufficiency. If a woman has previously lost a pregnancy in the second or third trimester, vaginal ultrasound during the next pregnancy may help predict if she's at risk for preterm birth
Providers sometimes recommend:
- Bed rest and reduced physical activity. While these methods are common, research has
not proven them to be effective.
- Pelvic rest. This means no sex, tampons or douching.
- Cerclage. The doctor puts a stitch in the cervix to keep it from opening too early. The
stitch is removed at about 37 weeks of pregnancy. Join the discussion group about cerclage on the March of Dimes online community Share Your Story.
Last reviewed April 2012