The Risks of Laboring on Your Back
It continues to amaze me that medical staff are still willing to play chicken with lawsuits by continuing to coerce women onto their backs to push in the 2nd stage of labor.
How much avoidable oxygen deprivation during pushing are you willing to accept for your baby? Zero, is what most parents tell me, it’s non-negotiable - but telling me won’t help you. Tell your OB.
If you’re already well informed on the 2nd stage of labor you’ll know that upright positions work with gravity, reduce pain and reduce unnecessary labor stress on your baby. Pushing on your back while holding your breath is like pushing your baby UPHILL due to the shape of the pelvis. Your baby has to go down under the pubic arch and then go up against gravity if you’re on your back. Sustained breath-holding reduces even more oxygen to your baby and affects your cardiac output.
The supine position is linked to stillbirth in pregnancy. So why is it ok in labor? I don’t know any parents who would volunteer to lie in a painful position known to increase complications for mom and baby - just to make their provider more comfortable with their lack of skills of receiving a baby in ANY other position.
Two recent studies will be helpful for you to include in your birth preferences and discuss ahead of time with your provider. Keep in mind your provider could be called away and you may end up with a provider who is NOT on the same page as you. Hopefully as you’re reading this you’re feeling relieved and reassured that your OB practices evidence-based, respectful, safe care or you’ve found a way to access midwife led care.
The first study (Jani et al., 2023) investigates the potential harm to a growth-restricted baby when mom lies on her side or back. Babies that are growth-restricted experience more oxygen deprivation. Ironically some of these labors are induced and mom ends up pushing on her back unaware of the potential harm to her already compromised baby… (FGR = fetal growth restricted, AGA = appropriate gestational age).
This was only for 25 minutes…and mom wasn’t holding her breath to push during this MRI.
Another study from 2021 shows equally worrying figures when women lie on their back in late pregnancy.
The results of this study provide further evidence that even short periods in the supine position (20–30 min) act as a stressor to the fetus.
The authors speculated that their results may be tolerated in a healthy baby but is potentially a major stressor in an unwell baby such as one with growth restriction (Warland & Mitchell, 2014). The data presented in this study show that in healthy late gestation pregnancy, when women lie on their back their baby experiences an estimated 6.2% oxygen reduction, and an average 11% reduction in flood flow to the placenta.
Even with an epidural you can be supported to change position - even upright on all fours is possible depending on how dense your epidural is (can you lift your legs and move them on the bed?). I’ve written about the benefits of having separate epidural birth preferences in the past. Even if you don’t plan to have an epidural it helps to understand how to optimise this tool and minimise potential tradeoffs - in the event you changed your mind on the day.
Birth can be unpredictable - do as much as you can to stack the odds in your favor of things going really well, bring a list of questions to your prenatal visits and don’t try to change your provider’s routine practice. Think about changing providers. Yes you can fire your OB in labor…I don’t recommend it due to the stress it can cause mom but sometimes parents are left with no other choice.
Start writing that list of questions - the links I’ve included throughout will help you have a meaningful discussion with your provider. I hope it goes well so you and your partner can spend the next few weeks feeling excited for your baby’s birth knowing you’ve stacked the odds as much as you can.
As always reach out to me anytime!
Tracy
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