VBAC v.1

VBAC Risk Score for Successful Vaginal Delivery (Flamm Model) is used to assess women in labor with history of caesarean section delivery for the likelihood of a successful vaginal delivery.

Syeeda S Farruque

models@cambiocds.com

© Cambio Healthcare Systems

This tool assists in planning the labour of pregnant women as to whether they can safely have a vaginal delivery or not.

The tool has a score range between 0-10 across 5 variables: Maternal age < 40 years: No - 0; Yes - 2 Vaginal birth history: 0 to 4 Reason other than failure to progress for first cesarean delivery: No - 0; Yes - 1 Cervical effacement at admission: 0 to 2 Cervical dilation ≥ 4 cm at admission: No - 0; Yes - 1 Score interpretation: Score % of women with successful vaginal delivery 0 - 2 49 3 60 4 67 5 77 6 89 7 93 8 - 10 95

As a cervical examination is required to assess the score, the tool can only be used after labour has started and the patient has been admitted. Although a high VBAC indicates likely successful vaginal delivery, a low score would not necessarily indicate that vaginal delivery might fail, the clinician should use their informed judgement

Ref. 1: Flamm BL, Geiger AM. Vaginal birth after cesarean delivery: an admission Ref. 2: Dinsmoor MJ, Brock EL. Predicting failed trial of labor after primary cesarean

OBSERVATION.basic_demographic.v1, OBSERVATION.vbac.v1, EVALUATION.vbac_risk_assessment.v1