The Science of "mum brain" and how you can support yourself

Pregnancy literally reshapes the brain

More times than I can count I have put things in the wrong place, walked into a room and forgot what I was doing, put my phone down and forgot where I put it two minutes later.
'Mum brain' is the butt of jokes, its used as a way to reference being forgetful, silly and even stupid.

But in reality pregnancy and motherhood physically changes your brain. It is one of the most profound biological transformations a woman will ever experience.
In a study published in Nature Neuroscience, researchers scanned the woman's brains before and after birth and what they found was that pregnancy caused significant structural changes in the brain particularly in areas responsible for empathy, emotional awareness, and social understanding.

Specifically, parts of the brain showed reductions in grey matter volume. When I first read this, it sounds concerning. However, researchers believe this change is actually a refining process, similar to the way the brain develops during adolescence.
Instead of losing ability, the brain is fine tuning neural connections to become more efficient at understanding and responding to a baby’s needs.
The brain is literally adapting to help a woman become a mother - I think that is incredible!!
What is even more incredible, is that these changes can last for up to two years after child birth and even suggests that pregnancy may permanently reshape parts of the brain.

So when you feel more emotional or more sensitive to your child, there is a biological reason, your brain has literally reorganised itself.

The hormone storm

At the same time your brain is reshaping itself, pregnancy and birth trigger one of the largest hormonal shifts a human body can experience. During pregnancy and postpartum, hormones rise and fall dramatically as the body adapts to growing and caring for a baby.
These hormones influence mood, sleep, memory, stress responses and the bonding with your baby.

Oxytocin surges during birth and breastfeeding and plays a major role in strengthening the bond between mother and baby.
Meanwhile, rapid drops in estrogen and progesterone after birth can affect mood and energy levels.

When you put all of this together, it explains why so many women say things like: "i feel like a different person" "why does everything feel so overwhelming".
Scientists now have a word for this transition, it’s called matrescence. Just like adolescence is the transition into adulthood, matrescence is the physical, emotional, and neurological transformation into motherhood and like any major life transition, it can feel confusing while it’s happening.

Ways to support your brain and hormones

While motherhood rewires the brain and body, research suggests there are simple habits that help regulate the nervous system and support hormonal balance. Not complicated routines, just small things that gently support your biology.

1. Morning Sunlight

   Exposure to natural light helps regulate the body’s circadian rhythm, which plays an important role in hormone regulation and mood.

   Even 5–10 minutes outside in the morning can help reset your brain and signal to your body that a new day has started.

2. Slow Breathing

   Slow breathing activates the parasympathetic nervous system, the part of the body responsible for rest and recovery. This helps lower stress hormones like cortisol and calm an overwhelmed nervous system.

   Try this simple reset:

   Inhale slowly through your nose for four seconds.

   Exhale slowly for six seconds.

   Repeat for one minute.

   Your brain will literally begin to relax.

3. Gentle Movement

   Walking and light movement help increase dopamine and serotonin, chemicals that support mood and emotional regulation. You don’t need a gym session, a walk around the block with a stroller counts and your brain benefits either way.

4. Talking with other Mothers

   Research consistently shows that social support significantly improves maternal wellbeing, sharing experiences with other mothers reduces stress and helps regulate emotional responses.

These small steps aren’t a magic fix, motherhood is complex, and every woman’s body and experience is different. What helps one mum may feel harder for another. But the research shows that supporting your nervous system, getting natural light, moving your body gently, and connecting with other mothers can help regulate the brain and hormones that are working so hard during this season of life.

They’re small things, but small things done consistently can shift how your body and mind feel after a few days, or a few weeks, you might begin to notice something subtle change maybe you feel a little more calm, a little more clarity a little more space to breathe inside the chaos of motherhood.
Sometimes caring for yourself doesn’t have to be complicated, sometimes it just starts with one small step and I hope you get some worth out of this post.

Grace xo

References

1. Hoekzema, E. et al. (2017). Pregnancy leads to long-lasting changes in human brain structure. Nature Neuroscience.

2. Barba-Müller, E. et al. (2019). Brain plasticity in pregnancy and the postpartum period.

3. Buckley, S. (2015). Hormonal Physiology of Childbearing.

4. Wu, X. (2025). Postpartum hormonal changes and maternal physiology.

5. Orchard, E. (2023). Matrescence: Lifetime impact of motherhood.