EARLIER this year, a study by Debenhams found that women keep their bras for, on average, five years, with nearly a third of those surveyed saying they've never been for a proper bra fitting.
Given that our busts change over time – for hormonal reasons as well as weight gain or loss – chances are your bra size has fluctuated too.
"Millions of women are wearing the wrong size bra and as market leader it's our mission to help them find one that fits perfectly, whether it's a first bra, a post-surgery bra or a pregnancy bra," says Julia Mercer, head of bra fit at Marks & Spencer.
The retailer is currently running a campaign to encourage women to go into an M&S store for a fitting and to donate any of their bras that no longer fit.
These will be resold or recycled by Oxfam, in the UK or as part of the charity's Frip Ethique social enterprise project in Senegal.
But how do you know if you're wearing the wrong size? Your bra might feel comfortable, but Mercer says there are five ways to tell, by looking at how it sits and fits on your body.
Follow these pointers to find out whether you need to think about swapping to another size.
1. Under band: Marks and Spencer Collection Pale Mauve Body Smoothing Longline Plunge Bra
2. Front wires: Figleaves Smoothing Strapless Balcony Bra
3. Side wires: Nine by Savannah Miller Navy Satin Underwired Padded Plunge Bra
4. Cups: Pretty Secrets Animal Mesh Padded Balcony Bra
5. Straps: M&Co Padded Grey Floral Underwire Bra
