Pregnant woman wondering how does hypnobirthing work

The science of hypnobirthing & how it works

‘Hypno-whaaat?’ is a fairly standard response when people hear what I do! There is a healthy dose of scepticism surrounding what admittedly sounds like some bonkers alternative way of chanting your way through labour, completely out of it. I often think that hypnobirthing needs a good re-branding so as not to lose people at the outset! Nothing about the weird name makes it clear that the science of hypnobirthing is super-simple and actually presents you with evidence-based ways to stack the odds in favour of a smooth & more comfortable birth.

Rather than any pendulum swinging or making you cluck like a chicken, what you will find is really enjoyable tools and techniques that are grounded in basic neuroscience & the physiology & mechanics of how the uterine muscles actually work during labour & birth.

Birth partners are usually the most cynical when they arrive at classes as they are often just coming along in support & wondering what on earth they’ve been signed up for! Let me tell you, they are often my biggest converts, when they realise how logical & common-sense it all is, and just how involved and integral they can be in positively influencing how birth goes…

The positive implications of preparing birth partners well for a supportive role in birth, both with regards to them having ways to manage their own stress levels during the birth & in being a more active participant is well documented and hypnobirthing certainly fits that bill! Check out more on this from The Fatherhood Institute.

So, how does hypnobirthing work?

There are two very simple & logical purposes to the ‘hypno’ bit of hypnobirthing:

  • 1
    Using positive reinforcement to reduce anxieties and build up your confidence in your capabilities
The word Fear in the dictionary to represent fear of birth

You may or may not have realised that women’s fears of what might happen during birth, expectations that it might be very painful, thoughts of all those things that can go wrong are totally LEARNT? It might be a little lightbulb moment when it’s pointed out that there is not one other mammal on this earth that DOUBTS it’s ability to give birth (or one that has such apparent difficulty with a completely physiological, involuntary action of the body!).

Nope, our doubts & worries come from years of hearing horror stories, seeing dramatic scenes of emergency and agony on TV/in movies and from a general cultural shift in society that has moved birth away from being a normal life event towards birth being a viewed as a ‘risky’ medical event.

The trouble is, that when we are frightened or anxious (and often this is a subconscious thing when it comes to birth) our bodies respond! Our minds are very much connected to our bodies and there’s no better example than the fight or flight response. When we are faced with a threat, whether it is real (such as someone jumping out at us from a dark alley) or just perceived (watching that horror movie from behind a cushion), certain hormones kick in and flood our bodies to help us deal with the threat.

One of the most notable hormones here is adrenaline, which acts to redirect our blood supply to where it’s needed – the legs (for fighting the threat) and the arms (for flight from the threat). You will at times I’m sure have noticed your heart racing, muscles tense up, skin tingling, hands getting clammy, & your senses sharpen when you’ve had a fright – this is the adrenaline surging through your body and the blood being pumped to where it’s needed most.

A pregnant deer standing on grass

Now, when a deer out in the wild is about to give birth she will instinctively choose somewhere that feels safe & private. But, if she hears or senses a potential danger nearby then the whole birthing process stops! Why would her body want to hurry up and birth her baby if there’s a predator around? The deer’s fight or flight response kicks in to ensure she can handle the threat effectively. Adrenaline redirects her blood supply to the legs for escape, which means that none of the lovely oxygen & resources it carries will be going to non-essential organs such as the uterus.

Not only that, but adrenaline acts to actively suppress one of the most vital hormones required for labour – oxytocin! Oxytocin is needed in huge amounts during labour & is responsible for producing & maintaining the contractions that open the cervix and move the baby down the birth canal. For this deer, her body’s survival response to fear has a very important function in slowing down or shutting down her labour. It may just save her & her baby’s life.

As women in labour, however, we are unlikely to find ourselves in a situation where the fight or flight response is a useful survival response! I hope you won’t be running anywhere or fighting with your midwife!! But we are mammals, and our minds & bodies interact in the very same way. It is unfortunate that what separates us from other mammals is our big old brains - our ability to overthink things, to try to rationalise things rather listen to our instincts.

Chemical depiction of oxytocin - The science of hypnobirthing

And years of negative input that almost programs us from a young age to expect the worst from birth tends to create a bit of a self-fulfilling cycle where anything from lurking little niggles of worry to full-blown dread of labour & birth throws the hormonal balance out on the day. If we don’t address it, fear can totally sabotage a birth experience.


So, just like hypnotherapy for fear of flying, or quitting a smoking habit…this side of hypnobirthing helps you break the cycle of negative thoughts that will hold you back & can interfere with the flow of the magical hormones needed to keep your labour progressing & on track. Adrenaline has a lot to answer for in many labours that require intervention, so learning how to keep it at bay is an essential that should be at the top of your birth planning to-do list! A bit more of an in-depth look at the birthing hormones can be found in this article by AIMS.

  • 2
    Practising deep relaxation techniques to help you remain calm & keep your body relaxed during labour & birth

Ok, so we know that when we encounter a stressful situation, our muscles tense up so addressing our worries about labour well ahead of the day itself is mega-valuable. Being able to relax very deeply & on demand (what is sometimes known as getting in ‘the zone’!) is a game-changer when it comes to labour as it helps you keep your mind quiet from distraction & anything that might disrupt your emotional calm (amazing if your circumstances change during labour too) but it also is a vital ingredient for the uterine muscles to work at their most efficient & comfortable!

A pregnant woman doing a strong arm during Bristol Hypnobirthing

The uterus is basically a pair of muscles (like most areas of the body), which are designed to work together very fluidly. A good example of this elsewhere in the body is the bicep & tricep muscles of your arm – in order to bend your arm, your bicep muscle contracts whilst the tricep relaxes….when it’s time to straighten your arm again, these muscle functions reverse & the bicep relaxes whilst it’s the turn of the tricep to contract/work.

Your uterus is made up of vertical muscle fibres (which remain soft and stretchy during pregnancy to accommodate your growing baby), and horizontal loops lower down forming the cervix/neck of the womb (which remain firm during pregnancy to hold your baby in until the time is right). During labour the functions of these muscles reverse, with the vertical muscles starting to contract/work and the horizontal muscles softening.

The way these muscles are designed to work together means that as the vertical muscles contract and draw upwards, they pull gently on the soft and now stretchy cervix so that it thins out and opens  – think of it a little bit like a turtle neck jumper where the neck is slowly drawn down over your head, opening it wider!


When muscles hold tension, it interferes with the fluid way muscle pairs work together, making actions that would normally be very easy & comfortable become very strenuous & uncomfortable. Try wiggling your fingers with relaxed hands – the muscle pairs all work well together and you could do it for quite some time (finger muscles are designed to wiggle!). Now try it again but tense your finger muscles into a claw-hand. It’s not a particularly pleasant experience!

Tense muscles will battle against each other whereas relaxed muscles are able to do their thing much more smoothly & comfortably – and here's the obvious but often overlooked thing….uterine muscles are designed to work together during labour & birth just as finger muscles are designed to wiggle! And if uterine muscles are able to work at their best together, then each contraction is going to be as effective as possible at drawing open that cervix, and likely to be more comfortable too. You can read a bit more about how contractions work in this lovely blog from Gather Birth

Trust me, being able to relax quickly & on demand is a total winner when you’re giving birth to a baby! But this kind of relaxation is a real skill and does have to be learnt & practiced. The techniques you will learn in hypnobirthing work in a conditioning way (hence the ‘hypno’ word again), you are really training your mind & body to relax in the weeks/months leading up to birth so that on the day you do not have to consciously think about what to do – it will be second nature to you. And this will of course be an invaluable life skill well beyond the birth too….

Woman enjoying pregnancy relaxation in Bristol

So, that’s a little whistle-stop delve into what the ‘hypno’ bit of hypnobirthing is all about & how it works so well! Here I’ve really only scratched the surface of the science of hypnobirthing, I can’t cover it all in a blog post! But I’m hoping that you’re getting on board with the fact that it’s not some strange thing to be avoided – it’s skills & information that every pregnant woman should know!  The best way to get yourself totally clued up is to book onto a full course (which of course is a complete antenatal education providing everything you need to know to plan for a positive birth, not just the ‘hypno’ techniques).


I can promise there’s no pendulum swinging, no being under anyone else’s control, no chanting or being made to do anything uncomfortable or cringey during our courses! There’s no weirdness included…just 100% evidence-based & enjoyable tools & techniques that will allow you to help rather than hinder the birth process. What could be more valuable than turning your worries into calm & confidence and feeling empowered to help yourself rather than just ‘winging it’ on one of the biggest days of your life?

Intrigued by the science of hypnobirthing? Want to know more?

1 Comment

  1. […] should definitely also check out my blog post on the science of hypnobirthing for a more detailed look at the physiology of those birthing hormones and the muscles of the […]

Leave a Comment