Sonographic evaluation of the uterine cervix.

Ultrasonographic evaluation of the uterine cervix has been shown to help predict patients who may be at an increased risk for preterm delivery. The use of ultrasound in at-risk patients may improve the selection of those needing obstetric intervention, which therefore, may improve outcome and lower overall health care costs. Cervical competence, once thought to be a categorical variable, should now be thought of as a continuous variable, as the shortest cervical lengths are found in those women with a history of very early preterm delivery (> 24 weeks). Adjunctive tests, such as fetal fibronectin Bishop scoring and bacterial vaginosis may help to improve the accuracy of prediction of preterm birth; therefore a multifaceted risk approach to preterm birth is suggested in this article.