Vaginal birth after caesarean (VBAC) in Sydney: Honest review of the evidence
If you have had a caesarean and are wondering about your next birth, you have probably noticed how much noise there can be when you begin to consider your choices.
This is a plain, evidence-based overview of planning a vaginal birth after caesarean, a VBAC, written by a Registered and Endorsed midwife in Sydney. It will not tell you what to do. It will show you what the evidence says, where that evidence is shakier than it is often made to sound, and the questions that keep you at the centre of your own care.
What is a VBAC?
A VBAC is a vaginal birth after a previous caesarean. After one caesarean, your next birth is broadly a choice between two reasonable paths: a planned VBAC (planning to labour and birth vaginally, which ends either in a vaginal birth or, if needed, an unplanned caesarean), or a planned repeat caesarean (a booked surgical birth). Neither is automatically safer. They carry different risks, some during this birth and some for the pregnancies that come after. The right choice is the one that fits your history, your circumstances, and what matters to you.
How likely is a vaginal birth after caesarean?
More likely than many women assume. Most women who plan a VBAC and go into labour do birth vaginally. Somewhere between 6 to 8 in every 10 women planning a VBAC will have a vaginal birth, which means about 2 to 4 in 10 will need a caesarean. The major guidelines do not agree on a single figure, landing anywhere from about 60 to 80 per cent, and that spread is itself a useful reminder: this is an estimate, not a promise.
Some things point toward a vaginal birth, in particular a previous vaginal birth (the strongest single factor), a first caesarean for a one-off reason such as the baby's position, and going into labour on your own. Other factors, such as induction of labour, can lower the chance of a vaginal birth, so they are worth understanding properly before you agree to them.
One word of caution about online "VBAC success calculators": the original, widely used calculator scored women lower simply for being Black or Hispanic, a bias with no basis in biology that was only removed in 2021. These tools can feed a conversation, but they should never decide your birth, and they tend to be least accurate exactly when they discourage you.
Understanding the risks in proportion
The serious risk specific to a VBAC is the caesarean scar coming apart in labour, known as uterine rupture. It is real, and it is uncommon, and it deserves to be understood properly rather than feared vaguely.
In spontaneous labour, with one previous lower-segment caesarean, uterine rupture happens in about 1 in 200 women, around 5 in every 1,000. Said the other way, about 995 in 1,000 will not experience it. On the scale doctors use to describe risk, that sits in the "uncommon" range. Two things push it higher: induction of labour (around 1 in 370), and induction late in pregnancy (as high as around 1 in 56). This is a large part of why letting labour start on its own matters.
It also helps to know the difference between absolute and relative risk. Absolute risk is the real chance something happens to you, for example "about 5 in 1,000." Relative risk compares two options, for example "twice as likely," and on its own it tells you very little. "Double the risk" might mean a rise from 1 in 1,000 to 2 in 1,000, which is tiny, or from 1 in 10 to 2 in 10, which is not. So whenever you are told something changes your risk, the question that cuts through it is: "from what, to what, in actual numbers?"
The part that often gets left out: future pregnancies
Most VBAC conversations stay fixed on this birth. But if you might want more children, the bigger picture matters. Every caesarean adds a scar, and the risks build with each one. In particular, the placenta can grow abnormally into the scar, a condition called placenta accreta, which is a leading cause of major bleeding and emergency hysterectomy. In women who also have a low-lying placenta, the chance of accreta rises sharply with each caesarean. A vaginal birth avoids adding another scar, so for a woman planning a larger family, a VBAC's biggest benefit may be for the babies still to come.
What actually helps your chances of a vaginal birth
No matter your starting point, there are evidence-based things that genuinely shift the odds and protect your experience whatever the day brings. Most of them come down to one idea: staying out of the cascade of unnecessary interventions, and keeping your body and mind in the best state to do what they are built to do.
The biggest levers are continuity of care and support in labour. The same known midwife through pregnancy and birth is linked to more vaginal births and to women feeling more in control. Continuous one-to-one support in labour, whether from a midwife or a doula, makes a vaginal birth more likely with no downside. Beyond that: understand your last birth first, choose a care provider and a place that genuinely support physiological birth, let labour start on its own where you safely can, stay home and supported in early labour rather than being admitted too soon, and stay upright and mobile.
Choosing your care in Sydney
In Australia, informed consent is not a form you sign. It is your right to be given honest information, the benefits, the real risks, and the alternatives, and then to say yes or no in your own time. You can accept or decline any intervention, for any reason, and you can change your mind at any point, including in labour.
That makes your choice of care provider one of the most important decisions you will make. It is reasonable to ask any provider how they feel about VBAC, what their usual practice is, how many of the women planning a VBAC with them have a vaginal birth, and whether you can have a known midwife with you one-to-one. How those questions are answered, with warmth and real numbers, or with vague reassurance, tells you a great deal.
A free guide to take this further
Planning a VBAC: the free guide.
This article is a starting point. The full guide goes deeper into your real chances, the risks in proportion, what genuinely helps, and how monitoring, epidurals and consent really work, in plain language, with every figure sourced. It is free, and it is written to keep you at the centre of your own care.
If you would like to go further still, a Birth Review and Debrief can help you make sense of a previous caesarean before you plan the next birth, and a VBAC Birth Preparation Workshop in Paddington covers the evidence, your history, and the decisions ahead in a full day. You are welcome to start with the free guide and see where it takes you.
Jennifer Hazi is a Registered and Endorsed Midwife in private practice in Paddington, Sydney, and available Australia-wide via telehealth. This article is general information, not personal clinical advice. Always discuss your own situation with your midwife or doctor.
References:
RANZCOG 2025, Birth after caesarean (C-Obs 38), version 4.1, RANZCOG, Melbourne.
RCOG 2015, Understanding how risk is discussed in healthcare, RCOG, London.
Queensland Health 2015, Vaginal birth after caesarean section (VBAC), Queensland Clinical Guideline MN15.12, Brisbane.
ACOG 2019, 'ACOG Practice Bulletin No. 205: vaginal birth after cesarean delivery', Obstetrics & Gynecology, vol. 133, no. 2, pp. e110–e127.
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Silver, RM, et al. 2006, 'Maternal morbidity associated with multiple repeat cesarean deliveries', Obstetrics & Gynecology, vol. 107, no. 6, pp. 1226–1232.
ACOG & SMFM 2018, 'Obstetric Care Consensus No. 7: placenta accreta spectrum', Obstetrics & Gynecology, vol. 132, no. 6, pp. e259–e275.
Rogers v Whitaker [1992] HCA 58; (1992) 175 CLR 479, High Court of Australia.
ACSQHC 2019, Australian Charter of Healthcare Rights, 2nd edn, ACSQHC, Sydney.
WHO 2018, WHO recommendations: intrapartum care for a positive childbirth experience, WHO, Geneva.
