Does baby brain exist?

People often assume that pregnant women are suffering from 'momnesia'. But is there any evidence that having a bump affects your brain?
02 February 2016

Interview with 

Kat Arney, The Naked Scientists


A pregnant woman


Each week Kat takes scientific dogma to task and she asks "is there actually any evidence for that?"  - and this time the term 'mythconception', which is what we call this bit of the programme, is rather appropriate... A pregnant woman

Kat - If you're a woman in your 20s or 30s and enjoy idly scrolling through social media, there comes a time when you realise that the pictures of people having fun in the pub seem to have been overtaken by photos of your friends with bulging bumps, rapidly followed by pictures of their bouncing babies.

And inevitably, there will be comments about 'baby brain' and 'preg head', or 'momnesia' as it's known in the US - the commonly held idea that being pregnant and having a baby somehow affects your memory, making you flakey and forgetful. But is there any scientific evidence to support this?

The fact is that the evidence here is mixed. Some studies have shown that compared with women who weren't pregnant, baby-bearing women do worse at certain memory tasks, particularly if they involve short term memory. There's a particularly notorious study from 1997 showing that women's brains actually shrink during late pregnancy, and take a full six months to go back to normal.

Research with rats has shown that females actually seem to get mentally sharper after having a baby, and are better able to find food than those who've never had pups.

And a small 2015 study found no difference between pregnant women and mums, and those who had never popped a baby out.

Finally,  a recent analysis in the New Scientist magazine in January this year attempted to gather together all the evidence, concluding that while pregnancy and its hormonal storm does cause major changes in the brain and body, these aren't specifically linked to a change in mental agility.

So what other explanations can science offer for women who do feel that their faculties have gone to pot while they're baking their bump? Well, for a start there's the well-known effects on memory and learning of a lack of sleep - something that can certainly affect pregnant women and new parents. Then there's the psychological effects of shifting priorities and a new routine that a new baby brings. Some things just become less important and slip through the net when there's a tiny new life to think about, and it's impossible to remember everything.

Finally, there's also the phenomenon of confirmation bias: we all forget stuff and make mistakes - women with or without children, and men too. But if you're pregnant, you might be more likely to ascribe your errors to baby brain. And because women who've had children are still more likely to be discriminated against when coming back into work than the "sprog-less", it's high time to forget about the myth of baby brain.


Add a comment