Lack of utility of standard labor curves in the prediction of progression during labor induction.

Abstract

This study was undertaken to determine whether patients undergoing labor induction can be reliably evaluated by means of standard labor assessment curves. In this retrospective chart review of 123 patients who underwent cervical ripening and induction of labor, Friedman's standard labor curves were used for comparison. Statistical analysis was performed with the Student t test. Nulliparous and parous patients undergoing cervical ripening spent more time in active-phase labor than standard expectations of labor progression would indicate (12.7 +/- 7.8 vs 5. 9 +/- 3.4 hours for nulliparous women, P <.001; 7.9 +/- 6.4 vs 2.5 +/- 1.5 hours for parous women, P <.001). Nulliparous and parous patients who were delivered vaginally spent more time in active labor than did their respective standard historical control populations (10.3 +/- 8.0 vs 5.9 +/- 3.4 hours for nulliparous women, P <.001; 7.0 +/- 6.0 vs 2.5 +/- 1.5 hours for parous women, P <. 001). Standard methods for the evaluation of labor adequacy and prediction of the likelihood of vaginal delivery may not apply to patients undergoing cervical ripening.