How amniotic fluid protects you and your baby in pregnancy | Nature’s beautiful safety nets

Research has now shown that amniotic fluid serves many vital functions. (Karen Wilmot aka 'The Virtual Midwife' /Supplied)

Research has now shown that amniotic fluid serves many vital functions. (Karen Wilmot aka ‘The Virtual Midwife’ /Supplied)

Karen Wilmot aka ‘The Virtual Midwife’ is a midwife, prenatal yoga teacher and founder of The Due Date Club, a private online community for pregnant women. In this series she shares what she calls the ‘safety nets’ that nature has in place to protect you and your baby in pregnancy. As she says, each day and each symptom is an opportunity to learn what’s happening, what causes it and what you can do to optimise your health.


Amniotic fluid is the “water” people refer to when they say their “water broke.”

In the movies, it’s always portrayed as dramatic with a lot of screaming and shouting. In real life, only 1 in 10 women will experience the water breaking before going into labour.

But why is there water in the first place?  

Your body starts producing amniotic fluid about 12 days after conception. The membrane that holds the amniotic fluid is called the amniotic sac or “bag of waters.”

During pregnancy, your baby grows inside the amniotic sac (bag) inside your uterus.   

In the past, doctors thought that protecting the baby was the fluid’s only significant function. However, medical research has now shown that amniotic fluid serves many vital functions: 

• It acts as a cushion around your baby, protecting it from any bumps to your belly. 

• It creates a watery environment that allows your baby to move freely. This movement helps your baby’s muscles and bones develop. 

• It helps maintain a steady temperature around your baby. 

• It helps your baby’s lungs grow and develop because your baby breathes in the fluid. 

• It helps your baby’s digestive system develop because your baby swallows the fluid 

• It protects the umbilical cord (the cord that carries food and oxygen from the placenta to your baby). 

• Its bacteriostatic action helps prevent infection of the intra-amniotic environment. 

The composition of your amniotic fluid will change throughout your pregnancy

In early pregnancy, it’s mainly water from your body. By 10 weeks, your baby’s kidneys start working, and urine is produced.

At the same time, your baby’s taste buds develop, and your baby starts swallowing.

This means that your baby passes urine into the amniotic fluid and drinks the amniotic fluid. It may sound gross, but amniotic fluid is completely sterile and contains essential nutrients, hormones and antibodies.

Drinking amniotic fluid facilitates the maturation of your baby’s gastrointestinal tract. It helps regulate the volume and composition of the amniotic fluid and is a vital developmental skill.  

Also read: How your placenta supports you and your baby in pregnancy | Natures beautiful safety nets

Your baby develops taste preferences before they are even born 

You may be surprised to hear that your baby develops taste preferences before they are even born.

As their sense of taste and smell develop, they react to the foods you eat.

Even before birth, babies show a preference for sweet tastes. Studies show that when sweet flavours were injected into the amniotic fluid, they swallowed more than when bitter flavours were introduced. 

This early preference for sweeter tastes continues when your newborn is fed breast milk, as it also has a sweet taste.

In another study, mums-to-be were asked to drink a lot of carrot juice in their third trimester. When their babies began weaning months later, they enjoyed carrot-flavoured cereal more than the control group whose mums hadn’t had the juice. 

You have the power to influence your baby’s likes and dislikes

Another study showed that babies whose mums had eaten a lot of star anise during pregnancy enjoyed the smell once they were born, while those that hadn’t had prior exposure didn’t.

These studies show that you have the power to influence your baby’s likes and dislikes through your own dietary choices, even at this early stage.

The development of food preferences starts in the womb and continues throughout breastfeeding.

Repeated exposure to certain flavours via the amniotic fluid and later through breastmilk is thought to influence your baby’s enjoyment of those flavours once they start weaning.

This taste imprint is thought to explain cultural preferences for certain herbs and spices.  

Also see: How your hormones help you have a healthy pregnancy | Nature’s beautiful safety nets

Your baby swallows about 450 to 500 mL of amniotic fluid per day

By the end of your pregnancy, your baby swallows about 450 to 500 mL of amniotic fluid per day (of the total 850 mL).

This complex sensorimotor process prepares your baby to coordinate suckling, swallowing, and breathing once they are born.  

Amniotic fluid is more than a safety net of pregnancy. It’s vital for the healthy development of skills that your baby needs to survive outside of your womb.

It’s clear that a healthy, balanced pregnancy diet provides you and your baby with more than just essential nutrients and that it can impact your baby’s experience with different foods during weaning. 

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