An incompetent cervix, also called an insufficient cervix, is a condition that occurs when weak cervical tissue causes or contributes to premature birth or the loss of an otherwise healthy pregnancy.
Before pregnancy, your cervix — the lower part of the uterus that connects to the vagina — is normally closed and rigid. As pregnancy progresses and you prepare to give birth, the cervix gradually softens, decreases in length (effaces) and opens (dilates). If you have an incompetent cervix, your cervix might begin to open too soon — causing you to give birth too early.
An incompetent cervix can be difficult to diagnose and, as a result, treat. If your cervix begins to open early, your health care provider might recommend preventive medication during pregnancy, frequent ultrasounds or a procedure that closes the cervix with strong sutures (cervical cerclage).