Here’s why ‘baby brain’ can change a new parent’s mind

The mental changes a mother goes through during pregnancy can be attributed to hormones, physical changes in the brain and sleep deprivation.

Photo credit: Dan Bright

Published: September 10, 2023 at 9:00 am

The changes a mother’s body goes through during pregnancy are complex, extraordinary and go far beyond a bulbous belly, cravings and swollen ankles. Many women also experience mental changes, such as forgetfulness, brain fog, poor attention and focus.

This is commonly referred to as ‘baby brain’ and describes the general feeling of not being quite on the ball mentally. Scientists have proven it is real and that the brain undergoes physiological alterations. 

Baby brain can strike as early as the first trimester and can last for years – even after the baby is born. Although the reasons behind it are not entirely understood, there are a few things we do know that may contribute to mothers’ temporary cognitive decline.

Hormonal changes

During pregnancy, a woman experiences significant hormonal changes, including surges in oestrogen and progesterone. Elevated levels of these two hormones have an enormous impact, both physically and mentally. They can affect our ability to think clearly, focus and recall information, causing a feeling of brain fog.

Studies have found that pregnant women may have particular difficulty remembering locations and spatial relations between objects, a cognitive function known as spatial memory. This explains why so many pregnant people are always searching for their car keys!

Pregnancy can also be a stressful time and heightened stress levels trigger the release of the stress hormone cortisol, which is known to affect brain function including memory, attention and decision-making. 

Sleep deprivation

Unfortunately, growing a baby and caring for a newborn is often accompanied by severe sleep deprivation. Insomnia can start early on in pregnancy and once the baby is born, sleep can become even more elusive.

This can contribute to baby brain because sleep is essential for the brain to restore its energy levels and carry out important housekeeping tasks, such as removing toxic waste and repairing brain cells, ensuring we wake up feeling refreshed and energised.

A lack of good-quality sleep can lead to poor memory, concentration and a general ‘zombie’ feeling.

Physical changes in the brain

Recent studies have found that women’s brains during pregnancy undergo some astounding physical changes that may contribute to baby brain. Scientists have discovered that pregnant women’s brains have dramatically reduced volumes of grey matter in the regions associated with processing social information.

It’s believed these adaptive changes help fine-tune and prepare the brain for maternal behaviour, such as learning to read the plethora of baby expressions and forming a strong mother-child attachment. So, while pregnant women might be losing their car keys repeatedly, they’re more than equipped to care for their baby – despite the presence of baby brain.

Although baby brain is understandably frustrating and upsetting at times, it is important to note that it’s a natural and common pregnancy symptom, and the mental fog does eventually clear. It’s all part of the body’s way of transitioning into motherhood. 

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