CERVICAL INCOMPETENCE, ULTRASOUND DIAGNOSIS, TREATMENT AND FOLLOW-UP

Abstract
Cervical incompetence has been the source of increasing controversy. Debate has raged over whether the entity actually exists. Controversy also exists concerning whether prophylactic cerclage is ever indicated or whether cerclage are only indicated when a short cervical measurement is obtained on transvaginal ultrasonography. We posit that cervical incompetence is not a categoric but rather a continuous variable, meaning that there are various degrees in the competency of the cervix. A short cervical length measurement in the late second or early third trimester seems to be useful in the prediction of preterm birth. In a prior study of 80 women we noted that placement of a cerclage resulted in a statistically significant increase in cervical length postoperatively. While the degree of lengthening immediately after the cerclage placement was not predictive of term delivery, a progressive shortening of the cervix after the cerclage was predictive of preterm birth. Until adequate randomized trials are conducted we suggest that serial transvaginal ultrasonographic measurements of cervical length be performed in women with risk factors for cervical incompetence and early preterm delivery. Those women truly at high risk of preterm delivery in whom a short cervical length (i.e., < 15-25 mm) is observed should undergo cerclage placement.

Key words
Preterm birth, cerclage, cervical incompetence, cervical length, transvaginal ultrasound.

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