Sonographic cervical length as a predictor of type of delivery after induced labor.

PURPOSE: This study was undertaken to evaluate the comparative value of sonographic cervical length and the Bishop score in predicting the type of delivery after induced labor.

METHODS

The Bishop score was determined by digital examination and cervical length by transvaginal sonography in 177 women.

RESULTS

The best cut-off points for predicting type of delivery found with ROC curves were 25.2 mm for cervical length and 5 for the Bishop score. The Bishop score was not predictive of type of delivery. Cervical length was related to type of delivery in women with Bishop score ≤5. A logistic regression model showed that only cervical length ≥25.2 mm, parity, and body mass index significantly predicted the likelihood of cesarean delivery.

CONCLUSIONS

Our study suggests that both Bishop score and sonographic cervical length can contribute to predicting type of delivery after labor induction, but cervical length is a better predictor of the risk of cesarean delivery.