Bishop Score

Excerpt

The Bishop score, introduced by Edward Bishop in 1964, is a cervical assessment system used to predict the success of labor induction. This scoring system evaluates several clinical parameters of the cervix, including dilation, effacement, position, consistency, and the fetal head's station in the pelvis. Each parameter is assigned a score, with the total score ranging from 0 to 13. Some experts have also implemented a modified Bishop score, in which cervical length may be used instead of effacement, and the highest score is 12. Although the precise criteria defining a cervix as favorable or unfavorable for induction have not been established, many studies have used a score of >8 using the traditional Bishop scoring system to indicate a favorable cervix or a score of ≥5 using a modified Bishop score, particularly in multiparous women at term with uncomplicated pregnancies.

The Bishop score is commonly used during digital cervical examinations at the time of induction to determine whether cervical ripening is necessary. Some studies have suggested that the Bishop score may not be as predictive of induction failure with newer cervical ripening strategies. Despite being a subjective assessment method, the Bishop score remains the standard technique for assessing the cervix before labor induction. Various mechanical and pharmacological interventions may be used in patients whose Bishop score indicates cervical ripening is necessary. This system is valued for its simplicity and effectiveness in predicting vaginal delivery, helping reduce the risks associated with emergency cesarean deliveries, which carry high morbidity and mortality for both mother and fetus. In recent years, transvaginal ultrasonography has emerged as an alternative for cervical evaluation. Studies have shown that cervical length measurements obtained through transvaginal ultrasonography can be a sensitive predictor of successful labor induction. However, research comparing transvaginal ultrasonography and the Bishop score has yielded mixed results, with no clear consensus on the superiority of one method over the other. Nonetheless, the Bishop score continues to be a widely used and trusted tool in obstetrics to determine cervical favorability and guide labor induction strategies.