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The SCIENCE of BIRTH - What facilitates labour and what gets in the way...

The shape of the pelvis, cocktail of hormones and powerful muscles of the uterus are designed to all work together harmoniously to bring our baby into the world, if we let them do their job...



As the saying goes: where the mind leads, the body follows i.e. what we put in our mind has a direct impact on the body. For example, smelling or seeing some delicious food being prepared or even just hearing about it might make you salivate or your stomach rumble. The same mind-body connection exists in childbirth: when we approach birth feeling fearful and expecting it to be painful, our bodies tense up, releasing the stress hormone adrenaline in preparation for ‘Fight or Flight’. And when our muscles are tense when we are trying to use them, we often experience pain which then causes more fear and so on. This is known as the Fear-Tension-Pain cycle. ⠀⠀⠀⠀⠀⠀⠀⠀⠀


So what causes the initial FEAR? So much of the deep-rooted fear that many of us have around birth is based on beliefs we have from our own upbringing and negative stories in the media (the very unrealistic and dramatic One Born Every Minute TV show, for example). It’s not our fault that we have been conditioned to fear birth, simply sadly a product of our time and culture BUT the good news is that this unhelpful cycle can absolutely be broken with techniques like Hypnobirthing which work on:⠀


- Addressing the FEAR i.e. Reframing the negative ideas that we take as facts, and creating new positive beliefs in pregnancy and birth. Being informed and prepared, about the process of birth and your choices and options can also help alleviate that fear.

- Addressing the TENSION i.e. Learning techniques to ensure muscles are as relaxed as possible and there is plenty of blood flow and oxygen to the uterus, helping each contraction to be as effective as possible. ⠀

 “When you change the way you see birth, the way you birth will change.” Marie Mogan ⠀⠀⠀⠀⠀⠀⠀


To put it simply, the uterus has two main layers of muscles: One runs vertically up and over the top of the uterus (the end finishing near the rib cage at full term) and one runs horizontally, forming bands or hoops around the growing baby and placenta.

- In PREGNANCY, the upper vertical muscles remain relaxed allowing for the baby to grow, while the horizontal muscles are contracted, holding the baby in and the cervix shut. 

- In LABOUR, their roles reverse: During a contraction, the vertical muscles contract and shorten, drawing the horizontal round muscles upwards to allow the cervix to thin and gradually open (to 10cm eventually). 

So we have two sets of muscles working beautifully together… why then do some women experience pain? 

If we are fearful or stressed, this activates our flight or fight response (see below) and has a direct effect on the body: we tense up. Vertical muscles are now pulling on TENSE horizontal muscles, rather than relaxed ones.  So we now have two sets of muscles working against each other, causing discomfort and pain. It’s a bit like trying to straighten your arm with both your biceps and triceps contracted… Really hard work! 

Breathing and relaxation techniques help keep the body and mind calm and relaxed, bringing plenty of oxygen and blood flow to the uterus muscles so they can work as a dream team, like they are designed to.


THE HORMONES: Oxytocin and Adrenaline

- The guest of honour: OXYTOCIN fuels labour by bringing on contractions. It also produces beta-endorphins, our very own painkiller - apparently FOUR times more powerful than morphine! Oxytocin is called the love or shy hormone as it is produced when we feel safe and loved e.g. during sex, when we have a cuddle, during birth and breastfeeding. Encouraging an oxytocin-friendly environment is really important in labour, as without it contractions may slow down or even stop. Think about where you would like to be having sex for example - it's likely that things like bright lights, interruptions and being observed would have an impact on the experience!

- The party crasher: ADRENALINE is the enemy of Oxytocin as we cannot produce both Oxytocin and Adrenaline at the same time. Adrenaline activates our ‘Fight or Flight’ mechanism, raising the heart rate and directing the oxygen/blood flow away from the uterus, to our arms and legs ready for fight or flight i.e. useless if we are trying to birth our baby! Adrenaline is produced when we feel stressed, fearful or tired so again minimising disruptions, conversations and creating a birth environment when you feel safe and relaxed can really help. Of course during labour there may be some situations where you do experience stress or fear - for example when transitioning from home to hospital, but you can get oxytocin production going again by taking your birth environment with you and using your breathing and relaxation techniques.

Tip for the journey to the hospital/birth centre: Sit at the back of the car with sunglasses/eye mask on, Headphones in with hypnobirthing or a relaxing playlist, lavender oil sprayed on a tissue and your water bottle to keep yourself in your zone

Book a free chat about Hypnobirthing here - absolutely no obligation to sign up afterwards of course!

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