Vaginal Birth After Caesarean (VBAC)

What is a VBAC?

The worldwide rate of caesarean section (CS) is increasing. In Australia, approximately 1/3 of babies are now born by either elective or emergency CS. As such, there are many women who required a CS in a previous pregnancy but who now wish to try for a vaginal delivery in this pregnancy (Vaginal Birth After Caesarean – VBAC). Dr. Colin Walsh is very happy to support this decision if it is your choice and there are no medical reasons which would make this choice unsafe.

Am I suitable to try for a VBAC?

The overall rate of successful VBAC is 70-75%. It is not 100% because there is always the risk of an unexpected problem in labour (unfortunately no woman can be guaranteed a vaginal delivery). Women considering VBAC should meet the following safety criteria:

  • 1 previous caesarean section only
  • Previous CS was a lower transverse scar on the uterus (not a “classical” CS)
  • This baby is in cephalic (head-first) position
  • No other indication for CS in this pregnancy (such as placenta praevia)
  • Informed consent to try for a VBAC

What are the benefits of a successful VBAC?

  • Avoiding another CS and all of the risks inherent in any major surgery
  • Quicker mobilisation and discharge home, to look after the rest of your family
  • High (90%) chance of vaginal delivery for all future children

What are the risks of attempting a VBAC?

  • 20-25% risk of an unsuccessful VBAC, requiring CS
  • 1-in-200 (0.5%) risk of uterine dehiscence (rupture) in labour requiring emergency CS
  • Slightly increased rate of 3rd degree tears in women who have successful VBAC

I am worried about the risk of uterine rupture

Uterine rupture is the most feared complication with VBAC but is thankfully rare. It refers to a situation where the scar on the woman’s uterus opens up during labour. The risk in spontaneous labour is 1-in-200 and in labour requiring oxytocin is 1-in-100.

How will a VBAC affect my labour?

  • Women should have an IV cannula (drip) inserted in case of an emergency CS
  • Fetal wellbeing should be monitored continuously during labour
  • Women have all the usual pain relief options available to them, including an epidural

Help!! I don’t know what to choose!

Don’t worry – you have lots of time. Although the option of VBAC is usually discussed early in pregnancy, this is to give you and your partner plenty of time to weigh up your options. You do not need to make a final decision until 36 weeks or so and an ultrasound scan to determine the baby’s weight and position at that time can be very helpful.

  • FRANZCOG
  • Mater Hospital
  • North Shore Private Hospital
  • The University Of Sydney
  • Royal College Of Obstetricians and Gynaecologists