Incompetent Cervix - Symptom & Treatment

An incompetent cervix will cause miscarriage at about the 20th week of pregnancy. An incompetent cervix thins and widens prematurely, usually between the third and thirteenth week of pregnancy. During pregnancy, while the uterus is enlarging, the cervix must remain closed.

There are many circular muscle fibers surrounding the cervix, especially the internal cervical os, which normally keep it tightly closed throughout pregnancy despite the continuous recurrence of Braxton Hicks' contractions. The condition can be treated with bed rest, medication and cervical cerclage surgery. Incompetent cervix accounts for up to 25 percent of all second trimester miscarriages.

The muscle surrounding the internal os may have been damaged so that it is incapable of keeping the cervix closed during pregnancy. The internal cervical os will then start to open soon after -the 14th week, and by about the 20th week of pregnancy the cervix will be about 2-3 cm dilated. At this stage the membranes, or bag of waters, will bulge through the cervix and will eventually break. Incompetent cervix is suspected when a woman has three consecutive spontaneous pregnancy losses during the second trimester (the fourth, fifth and sixth months of the pregnancy).

Causes and symptoms of Incompetent Cervix

The main causes of incompetent cervix are given below. Some factors that can contribute to the chance of a woman having an incompetent cervix include trauma to the cervix, physical abnormality of the cervix, or having been exposed to the drug diethylstilbestrol (DES) in the mother's womb. Some women have cervical incompetence for no obvious reason.

During a particularly difficult or rapid labor, or where a baby is unduly large, the muscle fibers of-the internal cervical os may occasionally be damaged and the next pregnancy miscarries at about the 20th week.

When the cervix is injured by excessive or forceful dilatation at an operation for the treatment of painful periods, or to perform an abortion, the circular muscular fibers around the internal cervical os may be damaged sufficiently to render the cervix incompetent in the next pregnancy. Fortunately this is relatively rare with the advent of prostaglandins etc. to facilitate these procedures.

Other major Causes and Complications of Incompetent Cervix are :

  • Previous surgery on the cervix
  • Damage during a difficult birth
  • Malformed cervix or uterus from a birth defect
  • Previous trauma to the cervix, such as a D&C (dilation and curettage) from a termination or a miscarriage
  • DES (Diethylstilbestrol) exposure

Common Sign and Symptoms of Incompetent Cervix are :

  • pelvic heaviness, discomfort, and lots of discharge.
  • Weakening from the previous childbirth,
  • surgery, or late pregnancy termination
  • inability to dilate can result from surgical trauma for which a colposcopy and cryosurgery is an alternative.

Very few women suffer from an incompetent cervix where there is no history or previous operation or pregnancy. In some cases, a pregnancy ends with miscarriage due to a spontaneous incompetent cervix, and no reason for the condition can be found. A future pregnancy has a high chance of developing an incompetent cervix without precautionary treatment to prevent cervical widening.