Predicting failure of a vaginal birth attempt after cesarean delivery.
OBJECTIVE
To identify a group of clinical factors that could be used to accurately predict failure in women attempting vaginal birth after cesarean (VBAC).


METHODS
We conducted a planned secondary analysis of a retrospective cohort study of women who were offered VBAC from 1996 to 2000 in 17 community and university hospitals. We collected information about maternal history and outcomes of the index pregnancy. We used univariable and multivariable statistical methods to develop a multivariable prediction model for the outcome of VBAC failure.


RESULTS
A total of 13,706 patients attempted VBAC, with a failure rate of 24.5%. Six variables were significantly associated with VBAC failure in our final logistic regression model: gestational age at delivery, maternal age, maternal race, labor type (spontaneous, augmented, or induced), history of vaginal delivery, and cephalopelvic disproportion or failed induction (combined variable) as prior cesarean indication. The area under the receiver operating characteristics curve is 0.717. To achieve a sensitivity of approximately 75%, a false-positive rate of approximately 40% would result.


CONCLUSIONS
Our results indicate that significant clinical variables (prelabor and labor) cannot reliably predict VBAC failure.


METHODS
II.
Srinivas
Sindhu K
SK
Department of Obstetrics and Gynecology, University of Pennsylvania Health System, Philadelphia, Pennsylvania 19104, USA. ssrinivas@obgyn.upenn.edu
Stamilio
David M
DM
Stevens
Erika J
EJ
Odibo
Anthony O
AO
Peipert
Jeffrey F
JF
Macones
George A
GA
D000293:Adolescent; D000328:Adult; D015331:Cohort Studies; D000075202:Contraindications; D005260:Female; D005544:Forecasting; D005865:Gestational Age; D006801:Humans; D016017:Odds Ratio; D011247:Pregnancy; D012372:ROC Curve; D012189:Retrospective Studies; D014219:Trial of Labor; D016064:Vaginal Birth after Cesarean / Q000009:adverse effects