Cesarean delivery after elective induction in nulliparous women: the physician effect.

Objective: The purpose of this study was to assess the contribution of the individual physician to the probability of cesarean delivery among nulliparous women who undergo elective induction.

Study Design: A cohort study compared spontaneous labor and elective induction for all term, singleton, and cephalic nulliparous gestations over 2 years (1999-2000) at a large metropolitan hospital (n = 3215). Bivariate analysis was used to identify significant variables that were related to cesarean delivery. Logistic regression analysis was used to calculate the adjusted risk of cesarean delivery and to assess the independent effect of individual physician practice on cesarean delivery. Physician effect was evaluated in terms of its relative contribution to the explanatory power of the logistic regression model to predict cesarean delivery.

Results: The adjusted odds ratio for cesarean delivery with elective induction was 1.78 (95% CI, 1.39, 2.27). Using forward stepwise regression, the individual physician was a significant independent risk factor in the model with an R square statistic increase from 0.194 to 0.249 when the physician statistic was added to the final model.

Conclusion: Nulliparous women are at a significant increased risk of cesarean delivery if elective induction is performed. The individual physician has a contributing effect to this increased risk.