Now that we've covered the what and the why part of the VBAC vs CS decision making process, now I'll move on to the 'how' - how can you help your chances of achieving your desired birth? Well, if you think elective CS is your best option, then the good news is that in your subsequent pregnancy, when your care providers offer you the choice, an elective CS will just be planned for you if you choose this option. Most women in Australia choose to have an elective CS instead of a VBAC. Most women who want a VBAC are usually successful (around 76% success rate) [6].

If you choose VBAC, they will still support you for this decision, but obviously there's a bit more water to go under the bridge before that is achieved! So I'm going to look at the factors that improve success (or don't) rates for VBAC.

First up: the public versus private healthcare sector.

It might surprise you to learn that where you are booked to have your baby has a huge impact on your outcomes. Paying money does not equal better outcomes. It might mean continuity of care (your choice of doctor) and reasonable hospital meals and a hotel stay afterwards. But again, you'll have to decide what's most important to you. 

Now, in the public sector in Victoria, the around 28% of women with a previous CS birth chose to attempt a VBAC, and over half (54.4%) were successful. In the private sector, only 14% of women with a previous CS birth attempt a VBAC, and 43% are successful [7]. Safer Care Victoria, which published this data, attributed these statistic to a "lack of choice, rather than better care". In other words, women aren't given much choice, or they don't have access to care that would allow them the choice. Similarly, it's an incorrect assumption to think that the private sector has a higher risk factor which contributes to lower rates of intention to VBAC and success - in fact, the public sector has more high risk pregnancies. So my first point is - if you want a VBAC, choose the public health care sector, or choose very carefully which obstetrician and private hospital you book with (and ask for recent statistics on VBAC). You can read more about your best options for maternity care here.

Secondly: your history

Perhaps unsurprisingly, your history when it comes to having babies will impact on your likelihood of a successful VBAC. If you've had a baby vaginally before (let's say your first baby was born vaginally, the second was an emergency CS for fetal distress), then your chance of a VBAC is well over 90%. Likewise, having a low-risk, healthy pregnancy increases your luck, and SOL (your body starting labour naturally - you can read my top tips for starting labour naturally here) increase your chances of successful VBAC.

Things that decrease the likelihood of a successful VBAC include previous difficult birth (dystocia), having your labour for VBAC induced (started artificially), maternal, fetal or placental complications in pregnancy, having a BMI above 30, a baby weight of 4kg or more, being an older mum, being short, or having more than one previous CS [1].

Now I do need to point out here, that many of these factors are a bit hard to define. Some will define an older mum as more than 37 years old, some might say it's when you're over 40. I think it comes down to the individual and how healthy they are when they fall pregnant (because a fit, healthy-eating, active 40 year old with no medical conditions probably has more chance of successful VBAC than an obese 35 year old with diabetes and high blood pressure). Likewise, it's impossible to predict the baby's weight before birth. Ultrasounds are notoriously inaccurate, especially the closer to your due date you are (meaning they are quite accurate at estimating size at 20 weeks, but not at 38 weeks). Please don't accept anyone's attempt to tell you your baby is big if it's based on them feeling your baby through your belly (inaccurate), or a one-off ultrasound. If you have an ultrasound in the weeks before your due date that suggests a big baby, please request a formal ultrasound by a skilled sonographer as a second opinion. Also - consider the size of your previous baby/babies - if they were well over 4kg, then chances are this one will be too. Each subsequent baby you have tends to be a little bigger than the last. Likewise, boy babies tend to be bigger than girls, so take that into account too if you know what you're having.

Another really important predictor of success is whether you've laboured before. The thing about labour and cervixes is - if it has dilated before, it will dilate much more efficiently and quickly in a subsequent birth. So if you've never laboured before, then you'll need to have patience in labour, as your cervix is doing everything for the first time. If you dilated to 7cm in your previous labour, then your cervix will dilate quickly to 7cm, then will do the rest of the birth as if it were your first labour/birth. If you laboured to 10cm (fully dilated), then it gets a bit tricky, and depends on the reason for your caesarean. If you were fully dilated, and pushing for hours and hours and your baby got stuck hence the CS, then that might tell you that perhaps babies don't fit very well through your pelvis. BUT, if your baby got stuck and was in the wrong position and got stuck, then you might be successful if your baby is in a good position for birth (and you'll need to hit up spinning babies to get your bub in perfect position!). In any rate, women who've dilated to 7cm or more in a previous birth are more likely to have a VBAC than those that haven't [9].