What Does VBAC Mean? (And HBAC, VBA2C?)

VBAC refers to ‘vaginal birth after caesarean’ – and it is exactly what it says on the tin!

Other variations of the acronym you may see include, HBAC ‘home birth after caesarean’ and VBA2C ‘vaginal birth after two caesareans’ (the number will be different depending on the number of previous caesarean births).

Why Do Some Women And Birthing People Choose a VBAC?

Some women may choose a VBAC because there are less risks associated with vaginal birth compared to caesarean birth (more on this below!). Others may want to experience vaginal birth. Or perhaps they have plans for a large family and want to avoid a repeat caesarean and the associated risks of multiple caesareans. The choice of VBAC is likely to be very individual to each woman or birthing person, in the same way that choosing a repeat elective caesarean section is a very individual choice.

What Are the Benefits of a VBAC?

Women and birthing people who plan and have a VBAC avoid the risks associated with the surgery of a caesarean birth. For example, the chance of having a postpartum haemorrhage, a blood clot or an infection is reduced. Physical recovery from a vaginal birth is generally quicker than a caesarean birth too. Immediate skin-to-skin is more achievable following a vaginal birth and babies born vaginally tend to have fewer breathing issues as they transition to life outside the womb. In addition, if having a vaginal birth experience was a priority for someone, there may be a real sense of achievement and a confidence boost following a VBAC.

What Are the Risks of a VBAC?

It is important to remember that no birth is without risk. When we’re looking at VBAC, the most feared and perhaps talked about risk is uterine rupture. Uterine rupture is a rare, but serious complication of pregnancy and childbirth. It is an obstetric emergency, where an opening develops in the wall of the womb and it can happen during pregnancy or in labour. The Royal College of Obstetricians and Gynaecologists (RCOG) in the UK state that the risk of uterine rupture is 0.5% (or 1:200) for women who have had a previous caesarean birth. Women who have not had a previous caesarean can also experience uterine rupture, although it is even more rare at 0.05% (1:2000). The increased chance of uterine rupture for women with a previous caesarean is due to there being a scar on the uterus. The chance of uterine rupture is increased 2-3-fold (this equates to a chance of 1 -1.5%) for women with a previous caesarean when labour is induced or augmented, compared to labours that start spontaneously – which is worth thinking about when planning your VBAC. 

There are differences in risk depending on the planned and actual mode of birth, Hazel Keedle has a great table of these in her book, ‘Birth After Caesarean’. Some women will plan a repeat caesarean, some will plan a VBAC but have an emergency caesarean and some will plan and have a VBAC. Research compared risks including uterine rupture, sepsis, postpartum haemorrhage and adverse outcomes for babies – overall the risk of these complications occurring was low across all modes of birth. There are higher rates of most of the risks for women who plan a VBAC but who have an emergency caesarean. But as Keedle notes, statistics only tell part of the story. Women’s personal experiences of their birth, whatever the mode, may tell a very different story.

What Does UK Guidance Say About VBAC?

The 2015 Royal College of Obstetricians & Gynaecologists (RCOG) green-top guideline ‘Birth after previous Caesarean birth’ notes that the success rate of VBAC is 72-75%. If you’ve also had a previous vaginal birth, the chance of success is even higher at 85-90%. In addition, a previous vaginal birth is also independently associated with a reduced chance of uterine rupture. 

The RCOG say that women planning a VBAC should be advised to birth in a hospital with access to immediate caesarean birth and advanced neonatal resuscitation facilities if needed. They also advise that continuous fetal (CTG) monitoring should be recommended as soon as there are regular contractions. Research has shown that one of the most common signs of uterine rupture is a fetal heart rate abnormality (usually a bradycardia, which is a persistent low heart rate), hence the recommendation for CTG monitoring to be able to immediately identify this occurring. However, we also know that CTG monitoring is associated with an increased likelihood of intervention. Other signs of uterine rupture include abdominal pain (continuous, not coming and going like contractions) and vaginal bleeding. Some women will be completely asymptomatic.

There has not been enough research into the safety or efficacy of VBAC for women who have a history of the following: twin pregnancy, post-dates, antepartum stillbirth, are aged 40 or over or fetal macrosomia (a suspected large baby) – therefore the RCOG advise a ‘cautious approach’ when considering VBAC for women with these circumstances.

The contraindications that exist for vaginal birth are the same for VBAC – so if conditions like placenta praevia (where the placenta has developed in front of the cervix, essentially blocking it) exist, a repeat caesarean birth would be necessary.

Can You Have a VBAC at Home or on a Midwife-Led Unit?

You can absolutely plan to birth at home or on a MLU if you’re planning a VBAC – in the UK we are lucky that you have the right to choose where you birth. It is worth noting that choosing to birth at home or on an MLU is considered ‘out of guidelines’ because as mentioned above, CTG monitoring and birthing on a labour ward are recommended. In the NHS you may be offered an appointment with an obstetrician or a consultant midwife to discuss your options and plans for VBAC if you’re choosing to birth ‘out of guidelines’. 

If you birth at home, there is no access to CTG monitoring – we use intermittent auscultation (that’s if you wish to have any fetal monitoring at all), where we listen to the baby’s heartbeat with a handheld doppler at regular intervals. There is also no immediate access to theatres for surgery or a neonatal unit, access to these is via ambulance transfer from home. If you choose to birth on an MLU it may be on the same site as the labour ward – therefore access to the emergency facilities is closer. There are many benefits however to planning to birth at home or on an MLU – so it is worth weighing up the risks and benefits to help you make your decision. The BRAIN tool can be particularly useful to get your thoughts down on paper. 

How to Decide What Is Right for You

Ultimately, you have to make the choice that feels right and safe to you. If you do plan a VBAC – know that the odds are in your favour! We know that birth is not and will never be without risk. The task is deciding what level of risk is acceptable to you. 

The 0.5% chance of uterine rupture may feel too high for some women to plan a home or MLU birth. For others, the 99.5% chance of not having a uterine rupture, may boost their confidence in planning a home or MLU birth. We know that labouring at home supports the unrestricted, physiological process of birth, but we also know that this won’t feel like the right choice for every woman or birthing person planning a VBAC. 

We would highly recommend reading Hazel Keedle’s book, ‘Birth after Caesarean’ – it has heaps of information in it, useful statistics and personal stories of women who planned a VBAC.

We are very happy to support women & birthing people planning a VBAC at home, so if this is something you’re looking for – get in touch to find out more.

Listen: VBAC – an interview with Dr Hazel Keedle on the Midwives Cauldron Podcast