Simplified Bishop score including parity predicts successful induction of labor.

Objective: Our objectives were to confirm the predictiveness of parity for successful labor induction and propose an improvement in the Bishop's score to take parity into account and simultaneously simplify the original Bishop score.

Study Design: Retrospective study of 326 deliveries induced by oxytocin and amniotomy before prostaglandins between January 1, 1987, and June 30, 1988. We conducted a univariate and then a multivariate analysis of the relation between successful labor induction - defined by vaginal delivery- and the components of Bishop's score and parity.