VBAC Calculator
Calculate probability of successful Vaginal Birth After Cesarean Section
VBAC Risk Assessment
Personal Information
Younger age generally increases success rate
Ethnicity affects success probability based on research data
Body Mass Index (Pre-pregnancy)
Obstetric History
Prior vaginal delivery significantly increases VBAC success rate
Previous successful VBAC greatly increases chances
Recurring reasons (e.g., cephalopelvic disproportion) may decrease success rate
VBAC Assessment Results
Assessment Summary
Age: 0 years
Ethnicity: white
BMI: 0.0 kg/m²
Prior vaginal delivery: no
VBAC history: no
Recurring indication: no
Medical Disclaimer
This calculator provides estimates based on research data and should not replace professional medical advice. Always consult with your healthcare provider about delivery options and risks.
Risk Factors Analysis
Example Case
Case: Sarah, 32 years old
Age: 32 years
Ethnicity: White
Pre-pregnancy BMI: 24.5 kg/m²
Prior vaginal delivery: Yes (first child)
VBAC history: No
Recurring indication: No (previous C-section due to breech presentation)
Assessment Result
VBAC Score: 75.2
Success Probability: 86.04%
Risk Category: High Success Rate
VBAC vs Repeat C-Section
VBAC Benefits
- • Shorter recovery time
- • Lower infection risk
- • Avoid major surgery
- • Reduce future pregnancy risks
VBAC Risks
- • Uterine rupture (~0.5-1%)
- • Emergency C-section need
- • Potential blood transfusion
- • Hysterectomy (rare)
Key Success Factors
Prior successful vaginal delivery
Previous successful VBAC
Younger maternal age
Normal pre-pregnancy BMI
Non-recurring C-section indication
Spontaneous labor onset
Understanding VBAC (Vaginal Birth After Cesarean)
What is VBAC?
VBAC stands for Vaginal Birth After Cesarean Section. It refers to delivering a baby vaginally after having had a previous delivery by cesarean section. TOLAC (Trial of Labor After Cesarean) describes the attempt to have a vaginal delivery, while VBAC is the successful outcome.
Who is a Good Candidate?
- •Previous low transverse uterine incision
- •No history of uterine rupture
- •Clinically adequate pelvis
- •No other uterine scars
Grobman Model
This calculator uses the Grobman prediction model, which was developed to estimate the probability of successful VBAC based on maternal characteristics and obstetric history. The model was validated in large studies and provides reliable risk assessment.
Success Rates
- Overall VBAC success rate: 60-80%
- With prior vaginal delivery: 85-90%
- With prior VBAC: 90-95%
- Without prior vaginal delivery: 60-70%
Important: These are statistical estimates. Individual outcomes may vary significantly.