Definitions and Choices
Delivery options for a woman who had a previous Caesarean delivery are:
| Delivery option | Description |
|---|---|
| Vaginal birth after previous caesarean delivery (VBAC) | Timing: 37 weeks or beyond
Setting: delivery suite that has
Key requirements:
Induction and/or labour augmentation should be proceeded with caution if considered necessary due to increased risk of uterine rupture and caesarean delivery. |
| Elective repeat caesarean section (ERCS) | Timing: after 39 weeks of gestation
Routine practices prior to Caesarean delivery:
If ERCS must be performed <39 weeks → consider maternal corticosteroids to reduce risk of neonatal respiratory distress syndrome |
Decision Making – VBAC vs ERCS
VBAC Suitability and Contraindications
Planned VBAC is suitable for:
- Singleton pregnancy with the baby in cephalic presentation, and
- 37 weeks or beyond, and
- Only had a single previous lower-segment caesarean delivery
Regardless of any previous vaginal birth
Women with two or more prior lower-segment caesarean deliveries may still be offered a planned VBAC, provided they undergo specialised counselling by a senior obstetrician regarding the individual risks and likelihood of success.
Key factors that make VBAC NOT appropriate:
| Absolute contraindications |
|
| Caution + decided by senior obstetricians |
|
Risk and Benefit (VBAC vs ERCS)
| VBAC | ERCS | |
|---|---|---|
| Maternal benefits | 72–75% success rate (the single best predictor of a successful VBAC is a previous vaginal birth, particularly a previous VBAC)
If VBAG is successful:
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| Maternal risks |
VBAC with induction and/or augmented labour has 2-3 fold increased risk of uterine rupture and 1.5 fold increased risk of caesarean delivery |
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| Fetal risks |
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