An incompetent cervix (cervical insufficiency, cervical incompetence) is characterized by a weak cervix that results in premature birth or loss of pregnancy. A healthy cervix remains firm and closed until the body begins preparation for birth.
When the cervix is incompetent, connective tissues may be inherently weak or the cervix may dilate too soon. When cervical incompetence causes preterm birth, the baby is delivered between the 16th and 22nd week, thus resulting in prematurity or miscarriage. Risk increases for those with three or more 2nd trimester miscarriages, but the rate of occurrence for a second preterm birth is less than 30%. Risk factors are heightened in those with a short uterus, those with medical or accidental cervical injuries and in women with connective tissue disorders.
Some women experience no symptoms of an incompetent cervix. They only become aware of the problem after a preterm birth. Others have symptoms that last for days or weeks, thus allowing time for a treatment plan that could lower the risk of preterm birth. Those with symptoms may experience:
An incompetent cervix cannot be diagnosed before pregnancy, but abnormalities of the uterus can be discovered through a physical exam and/or imaging. Tests can be performed in the second trimester to evaluate and monitor the pregnancy. They may include:
The treatment for an incompetent cervix depend on the level of risk for preterm delivery.