Childbirth is not a ‘pathology’, just as pregnancy is not a ‘disease’. Our beautiful bodies have been made so intricately that an intense process like childbirth will flow smoothly once it is left un-interfered. Don’t get me wrong, I am not suggesting people assigned female at birth (AFAB) choose unassisted birth. However, being a doctor and a childbirth educator, I know for a fact that the medical world has indeed disrupted the natural process of birth, leading to many hindrances. 

Overview of birth

Before we dive into the specifics of hormones, let’s have an overview of childbirth. Did you know that even now, we do not know ‘what’ exactly starts labour pain? The exact trigger of labour is still unknown. 

Childbirth can be broadly divided into three stages:¹

First stage

This is when the opening of the uterus (cervix) starts dilating until it reaches about 10cm. This stage may be divided into two phases: Phase one is the latent phase with moderate-strong contractions at approximately 10-15 min intervals. During this phase, the cervix opens up to 4-5cm. This is followed by the active phase, when you will experience stronger contractions at 3-4 min intervals, hence opening the cervix to 10cm.

Second stage

This is the phase of pushing. During this phase, you will feel strong urges to push the baby out. It usually lasts around 30 minutes. Many AFAB people find this stage easier than the first one as they find themselves doing ‘something’ for the feeling of pain. ‘Crowning’ occurs, which is when the baby’s head stretches the opening of the vagina to the maximum and the baby is born. 

Third stage

This is the final stage, which involves the passage of the placenta from the body. It takes about 30-60 minutes for the body to expel the placenta. 

Every person’s labour is different. Even one labour can differ from another for the same person. First-time parents may take anywhere from 10-20 hours for labour, and second-time births are usually quicker. 

This is the normal physiological process of birth. 

Now, how do our hormones play a role in this magical process?

A cocktail of hormones

There are four main hormones that are involved in the process of birth. Oxytocin, adrenaline, endorphins and prolactin. Some other hormones that also assist are oestrogen, progesterone, and prostaglandin.

Hormones are called the ‘chemical messengers of our bodies. Even though they cannot be seen by our eyes, these messengers play a vital role in the process of birth.

Oxytocin

This hormone is called the ‘hormone of love’ due to its prominent role in sex, ovulation, labour, birth and breastfeeding.² Oxytocin is also what creates the maternal feeling of loving and nurturing.

Researchers have found that the level of oxytocin receptors increases when pregnancy approaches term, and is at its maximum when the pregnant parent is in active labour.³ This is what causes the strong and hard contractions. Another important role of oxytocin is to help the pregnant parent birth the placenta after the baby is born. It also has a crucial role in the reduction of the uterus to its prepartum size and condition after birth.⁴

Oxytocin reduces stress, calms you down, and helps with pain from contractions. In lactation, oxytocin causes the ejection of milk during breastfeeding. Oxytocin also has a critical role in maternal-foetal bonding.

Sometimes, when the contractions are not strong or not enough time has passed, an artificial form of this hormone (syntocinon or pitocin) is administered by doctors. Even though it might speed up the process, synthetic oxytocin does not enter the brain, hence it doesn’t have the calming effect and usually disrupts the natural flow of the natural hormone within the body resulting in harder, almost unbearable contractions.⁵

So, in essence, oxytocin is a helpful hormone for birth, and we need more of it naturally. What are some factors that can help in its production? 

• It is extremely important to stay calm, comfortable and confident in the natural process of birth
• Try to free your mind of any emotional of psychological anxieties or baggage
• Avoid disturbances like uncomfortable positions, noise, unwelcome people or even unnecessary procedures
• Staying upright will help the baby put pressure on the cervix, stimulating its release
• Find a quiet, dark room with no disturbance, a place that will make you and your baby feel safe
• Before labour, nipple stimulation and sexual activity may also help increase levels of the hormone

Do you know why the parent tends to ‘forget’ the extreme pain they just went through after birth as they hold or see their baby? It’s the flood of oxytocin that takes over their feelings. 

Adrenaline or catecholamines

Contrary to the loving oxytocin, this hormone is called the ‘fight or flight’ hormone. Adrenaline (a type of catecholamine) is a survival hormone and is secreted when you feel threatened, in our case, pain and fear of birth cause its release.

Too much of this hormone may slow down the process of birth, especially during the first stage. It may also cause distress to the baby. Adrenaline creates a sense of urgency or panic, which leads to more pain. Panic causes shallow panting-like breathing patterns, resulting in more distress, and the pregnant parent can go into a panic cycle. 

Contrary to its negative effects in the first stage, adrenaline/catecholamines are actually helpful during the later stages. This is when you want to push the baby out. A surge of catecholamines will give you the boost of energy you need to do just that. 

For most of the first stage of labour, we need to lower these hormones. Some simple ways to do so include:

• Being informed and prepared prior to birth
• Trying to stay calm and comfortable
• Practising relaxation and deep abdominal breathing
• Being in a private, safe environment and avoiding conflicts
• Avoiding unnecessary interventions

Endorphins

Endorphins are the pleasure hormones or happy hormones. They are also released as a response to stress and panic but with the effect instead of calming the body. Their effect is similar to opiates or heroin! High levels of these hormones will help you to deal with the difficulty of labour and increase your endurance for long labour. Endorphins help you to feel alert, attentive, and sometimes even euphoric or semi-drunk.

These hormones are also responsible for prolactin release and hence aid in breastfeeding. After birth, these hormones also contribute to parent-baby bonding, and sometimes a drop in these might contribute to ‘baby blues’.

This is one of the good hormones, and to increase its level we should aim to have a calm and peaceful environment while avoiding unnecessary interventions and people. 

Prolactin

This is known as the ‘mothering’ hormone. Prolactin (as the name suggests) is responsible for the production of milk and preparing the pregnant parent’s body for birth. It is the major hormone for milk production. It increases as the parent reaches term and peaks at birth.

This hormone is also a useful hormone not only for breastfeeding but also for birth itself. Some ways to ensure adequate levels of prolactin in the body include:

• Allowing your body to go into labour on its own
• Early breastfeeding after birth
• Skin-to-skin contact with the baby after birth and thereafter

Oestrogen, progesterone and prostaglandin

These hormones also have an essential role in childbirth. During pregnancy, progesterone is at higher levels compared to oestrogen. Once you are nearing term, levels of both progesterone and oestrogen are almost similar. They are responsible for sending the message of ‘readiness’ for birth to your brain, and also for the contraction of the uterine muscles. Prostaglandin causes softening and dilatation of the cervix. An artificial form of this hormone is used for the induction of labour. 

As we have gone through the journey of birth with these hormones, it must be quite clear that we as humans don’t have an on/off button within our body. We cannot simply decide to exclude one hormone and have more of the other like in a chemistry laboratory. Think of it as a cocktail, where you have a mixture of numerous flavours, some more than the other. We may increase some flavours to make it desirable but it will always be a ‘cocktail’.

Summary

The article breaks down how hormones can help during childbirth, making everything work smoothly. We first went through the normal physiological process of birth. The first stage involves the opening of the cervix with increasing intensity of contraction (up to 10 cm). The second stage includes pushing the baby out. The third stage is the birth of the placenta. Key Hormones involved in childbirth include:

• Oxytocin: Known as the "love hormone," it causes contractions, eases stress, helps with mother-baby bonding, and gets the milk flowing
• Adrenaline: This is the "fight or flight" hormone. Too much of it in early labour can slow your progress; however, later, it gives you the energy boost to push
• Endorphins: These are your body's natural painkillers. They keep you calm, help you cope with labour, and even make you feel a bit over the moon
• Prolactin: Prepares your body for birth and is responsible for milk production during breastfeeding

What is the main takeaway from the article? 

Let these hormones do their work naturally and avoid too many interventions. Focus on maintaining the balance between hormones. This will make childbirth easier, and smoother and ultimately result in an empowering experience.