The power of hormones in pregnancy and labour

Your body does some pretty incredible things during pregnancy, labour, birth and breastfeeding. While you might think of these processes as something your body simply knows how to do, there are some powerful helpers working behind the scenes: your hormones.

There are four key hormones to be aware of during labour, birth and breastfeeding: oxytocin, endorphins, adrenaline and prolactin.

These chemical messengers travel through your bloodstream and play different roles throughout your journey. They help initiate labour, drive your contractions, provide natural pain relief, give you energy as you birth your baby and support breastfeeding and the development of the bond between you and your baby.

Understanding these hormones can help you appreciate what your body is doing and identify ways you can create an environment that supports their natural flow.

Hormones in pregnancy

Oxytocin: your love hormone

Oxytocin is often described as the ‘love hormone’. It is released when you feel loved, cared for and appreciated, and when you experience a deeply positive emotional connection with another person. It is released during everything from a warm embrace to intimacy and orgasm.

It is also one of the main hormones involved in labour. As labour begins, oxytocin signals your uterus to contract and continues to flow as your contractions become stronger, longer and closer together. These contractions help your cervix dilate and your baby move down through your pelvis. As your baby moves towards birth, you may experience an overwhelming urge to push.

Oxytocin reaches its peak around the time you and your baby meet for the first time, helping nature begin that incredible process of falling in love with your baby.

How can you support oxytocin?

Creating a positive environment can help support the natural flow of oxytocin during labour. This may include:

• Trusting in your knowledge of this incredible hormone and your body’s ability to labour and birth
• Creating a birthing environment that is private, warm, safe, relaxing, quiet, loving and positive
• Choosing your birth support people wisely and surrounding yourself with people who love and support you and understand your preferences for labour and birth
• Minimising unnecessary stress, tension or disruption during labour

Fear of labour and birth can affect the release of oxytocin. This may come from hearing negative birth stories, not having enough knowledge about labour and birth, or feeling that you do not have options.

An unfamiliar or stressful environment, noise, concerns about privacy, restrictions on movement or eating and drinking, anxiety, or feeling that you are not being listened to or respected can also make it more difficult to feel relaxed and supported.

Endorphins: your natural pain relief

Endorphins are sometimes known as your ‘happy hormones’. When they are released, they can create feelings of calm and general wellbeing. They are released when you smile and are also responsible for that happy feeling you can experience after exercise.

During labour, your body releases endorphins in response to rising levels of oxytocin and the physical work of contractions. These powerful natural pain-relieving hormones can help you remain calm as labour intensifies.

Endorphins also play a role after birth. They are released during breastfeeding and can help you feel relaxed as you spend time feeding and bonding with your baby.

How can you support your endorphins?

Trusting your body and connecting with the natural process of labour can help support your endorphin response. Comfort measures such as movement, changing positions and using gravity can help you cope with contractions.

Surrounding yourself with people you trust and creating an environment that makes you feel safe and supported can also help.

The same things that may affect oxytocin - including fear, stress, anxiety and feeling unsupported - can also affect your body's natural endorphin response. Some medical interventions or medications may also influence these hormonal processes.

Adrenaline: your response to stress

Adrenaline is often described as the ‘fight or flight’ hormone. When you feel threatened or in danger, your body releases adrenaline to give you the strength and energy to respond. It's an automatic response, for example, if you needed to run away from danger, your body could react before you had time to consciously think about it.

Adrenaline has an important role in labour and birth too. However, high levels of adrenaline during the earlier stages of labour can work against the hormonal environment that helps labour progress. Fear, pain, stress and panic can increase adrenaline levels, which can reduce the release of oxytocin.

This makes sense from your body’s perspective: if you feel threatened, your body prioritises keeping you safe. During labour, however, feeling calm, safe and supported can help create the conditions your body needs to focus on labour and birth.

Adrenaline also has a useful role later in labour, helping provide a burst of energy and alertness as you approach the final stages of birth and meet your baby.

How can you keep adrenaline in check?

Preparing yourself for birth can help reduce fear and uncertainty. Knowledge, confidence and trust in your body can all help you feel more prepared.

You can also:

• Attend childbirth education classes
• Take a tour of your birth facility so the environment is familiar
• Discuss any fears or concerns with your care providers
• Create a plan outlining your preferences for labour and birth
• Ask questions so you understand your options and can make informed decisions
• Communicate openly with your support people about the environment and support you would like during labour
• Stay calm, relaxed and mentally and emotionally prepared for birth

Understanding the relationship between your hormones can also help you see why feeling safe, supported and relaxed can be so important during labour.

Prolactin: your ‘mothering’ hormone

Prolactin is often referred to as the ‘mothering’ hormone. Its levels gradually increase throughout pregnancy and peak after the birth of your baby, where its primary role is to assist with breastmilk production.

Prolactin works alongside oxytocin during breastfeeding, helping to enhance the loving feelings and emotional connection between mother and baby.

How can you support prolactin?

There are several ways you can support the hormonal processes involved in breastfeeding.

• Keeping your baby skin-to-skin on your chest during the first hour after birth, and continuing skin-to-skin contact as much as you like during the first few weeks, can support bonding and breastfeeding
• Demand-feeding your baby can also support milk production. There is no need for a strict routine in the first few months of parenthood
• If you are breastfeeding, seek advice and support when you need it. Having the right information can help build your confidence, and relaxing and enjoying the time you spend with your baby can help create a positive breastfeeding experience
• Your partner can also play an important role by supporting you throughout your breastfeeding journey. Remember, you don’t have to do it alone.
• Most importantly, trust your amazing body. Just as it supports you through labour and birth, it is working to support you and your baby as you learn to breastfeed

There are some things that may affect the release of prolactin. Research has shown that artificial oxytocin used during labour may have an effect on prolactin release. Skin-to-skin contact and frequent breastfeeding can help reduce any impact this may have.

Being separated from your baby or experiencing a delay in breastfeeding after birth can also affect this process. Stress may reduce the release of prolactin, which is another reason why creating a positive, supportive environment can be helpful during your breastfeeding journey.

Working with your hormones

Your hormones are constantly communicating with your body and helping to guide you through pregnancy, labour, birth and breastfeeding.

Oxytocin helps drive labour and supports connection, endorphins provide natural pain relief, adrenaline helps your body respond when you need extra energy and prolactin supports breastfeeding and your developing relationship with your baby.

Understanding these hormones isn't about having a ‘perfect’ birth or controlling every aspect of labour. Rather, it can help you understand the incredible things your body is doing and identify ways to support yourself through the experience.

Feeling safe, informed, supported and connected can help you work with your body’s natural processes as you welcome your baby into the world.

References

The Family Way, Ways to Optimise the Hormonal Physiology of Childbearing, https://thefamilyway.com/wp-content/uploads/2017/02/WaysToOptomize.pdf

National Partnership for Women & Families, Hormonal Physiology of Childbearing, http://www.nationalpartnership.org/our-work/resources/health care/maternity/hormonal-physiology-of-childbearing.pdf

Sarah Buckley, Gentle Birth, Gentle Mothering (2005), https://sarahbuckley.com/

Childbirth Connection, The Role of Hormones in Labour and Birth, http://www.childbirthconnection.org/maternity-care/role-of-hormones/