What is a VBAC?
VBAC stands for vaginal birth after caesarean. It is possible for many women to have a vaginal birth after having a previous caesarean birth.
However, there are pros and cons to VBAC. There are also some situations where it is not considered a safe option.
What are the pros if a VBAC is successful?
- Avoid major abdominal surgery, which carries a small risk of complications
- Usually a shorter recovery period and shorter stay in hospital
- Higher chance of another successful VBAC in future pregnancies (whereas a repeat caesarean means all future births are likely to be by caesarean. The risk of complications for a caesarean is low, but it increases with the number of caesareans you have).
What are the risks?
The most common problem is that you end up needing an emergency caesarean in labour. Emergency caesareans have a higher risk of complications compared to planned caesareans.
A less common, but very serious, risk of VBAC is uterine scar rupture.
- The scar on your uterus is a “weak” point. It can tear open from the force of contractions.
- After 1 previous caesarean, the risk of scar rupture is approximately 1-in-200.
- If a hormone drip (syntocinon) is used to increase contractions, the risk of rupture also increases
- Risks to you after a scar rupture include dangerous bleeding and a small risk of hysterectomy
- Risks to your baby include a 1-in-500 risk of brain damage or death. This is higher than the risk to your baby of a planned caesarean section (1-in-1000 risk of brain damage or death).
When is a VBAC not considered safe?
- You have had two or more previous caesareans (the risk of scar rupture increases with each caesarean)
- Previous “classical” caesarean section, or other major surgery to your uterus (e.g. removal of large fibroids)
- You need a caesarean for other reasons, e.g. a placenta praevia
What factors affect the chance of having a successful VBAC?
- Whether or not you have had a previous vaginal birth
- Whether or not you go into labour spontaneously
- The time since your previous caesarean
- Other pregnancy complications
How will my labour be different?
- Ideally, you will go into labour and progress steadily on your own. We have fewer options available to safely induce labour. Also, we need to be much more cautious if your labour stops progressing.
- Continuous CTG monitoring of your baby’s heartbeat is strongly recommended throughout labour. The first sign of a uterine rupture is usually a sudden change in the baby’s heartbeat. The sooner we identify a rupture, the sooner we can act on it and hopefully reduce the severity of any complications.
- An intravenous cannula is often recommended at the start of labour. We can take blood ready to crossmatch and connect the cannula to a drip rapidly in an emergency.
As always, this information is only intended as a general guide. It does not replace advice from your doctor with a full assessment of your particular circumstances and individual needs. Please discuss your birth plan in detail with your own obstetrician.