Development of a nomogram for prediction of vaginal birth after cesarean delivery

Obstet Gynecol. 2007 Apr;109(4):806-12. doi: 10.1097/01.AOG.0000259312.36053.02.


Objective: To develop a model based on factors available at the first prenatal visit that predicts chance of successful vaginal birth after cesarean delivery (VBAC) for individual patients who undergo a trial of labor.

Methods: All women with one prior low transverse cesarean who underwent a trial of labor at term with a vertex singleton gestation were identified from a concurrently collected database of deliveries at 19 academic centers during a 4-year period. Using factors identifiable at the first prenatal visit, we analyzed different classification techniques in an effort to develop a meaningful prediction model for VBAC success. After development and cross-validation, this model was represented by a graphic nomogram.

Results: Seven-thousand six hundred sixty women were available for analysis. The prediction model is based on a multivariable logistic regression, including the variables of maternal age, body mass index, ethnicity, prior vaginal delivery, the occurrence of a VBAC, and a potentially recurrent indication for the cesarean delivery. After analyzing the model with cross-validation techniques, it was found to be both accurate and discriminating.

Conclusion: A predictive nomogram, which incorporates six variables easily ascertainable at the first prenatal visit, has been developed that allows the determination of a patient-specific chance for successful VBAC for those women who undertake trial of labor.

Level of evidence: II.

Publication types

  • Multicenter Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Adolescent
  • Adult
  • Body Mass Index
  • Contraindications
  • Female
  • Forecasting
  • Humans
  • Maternal Age
  • Nomograms*
  • Pregnancy
  • Pregnancy Complications
  • ROC Curve
  • Racial Groups
  • Retrospective Studies
  • Trial of Labor*
  • Vaginal Birth after Cesarean* / adverse effects