We often get asked why bra underwires break or pop through bras. First, let's talk about what a    bra underwire actually is and what it does.

A bra underwire is a flat piece of metal that has paint-coated tips. It's not rigid but is sprung and designed to flex and adapt to the body shape. Its main purpose is to provide shape and support to the bra.

At Rose & Thorne, we use individually shaped underwires for each of our different bra shapes (Oh Naturale, En Forme, Smooth Operator, and Curvylicious). So, for example, the underwire we use in one of our Oh Naturale bras would be different to the underwire we use in one of our En Forme bras. Likewise, we use a different underwire in our Full Cup Bras (designed specifically for D cup to G cup bras) and our Full Cup Premium Support Bras (designed for G Cup, H Cup and J Cup bras). 

So, why do underwires break or pop? Well, a number of factors come into play…

1. The bra you're wearing is the wrong body size.

If you're wearing the wrong size around the body (for example, you're wearing a size 14 instead of a 16), the bra is overstretched. This forces the underwire out of shape with repeated stress and tension on the metal. This can cause the metal to fracture and break free or force the wires through the casing. This often happens directly under the bust, at the edge closest to your arm, or at the center front between the breasts. 

2. The bra you're wearing is the wrong cup size.

When you're wearing a bra with the wrong cup size the breasts are essentially too heavy for the underwire and the metal will distort in the same way it does when you're wearing a bra with the wrong body size. A combination of the wrong body size and cup size can cause friction on the materials of the bra and shorten its life by wearing harder. We highly recommend getting a bra fitting - this way we can ensure you're wearing the right size.

3. Putting on your bra at the front.

We know lots of women do their bras up at the front and then twist it around the body to get the cups in place. Doing this places an enormous amount of stress on the underwires as the bra is dragged around the body. We recommend doing your bra up at the back if you can. Read on for more tips on how to put on your bra properly.

Washing your bra.

The best way to wash your bra is to do the hooks and eyes up, pop it into a wash bag and put the bag into the washing machine. The Rose & Thorne lingerie wash bags have been designed with tiny holes to allow all the washing liquids and water through, but not let the hooks catch on anything else in the wash.

Top tip - never use fabric softener as this can damage the elastics in the bra. Always follow the wash instructions and never tumble dry your bra - this can ruin the elastics and shrink the inner case of the wire channel. By shrinking the casing you have reduced the space the wire lives in and forces it out through the ends or sides of your bra when being flexed.

If you'd like more tips, read on to find the best way to care and wash your bra properly!

So, what can I do to avoid underwires breaking in the future?

We highly recommend a bra Warrant of Fitness - an annual fitting. If you've gained or lost weight, started at the gym, taken up walking or just haven't been fitted in while, pop in to get a professional bra fitting. Lots of women wear their bras for years and forget they've changed body shape and the bras have adapted. Over time the bra will have stretch out and eventually, it will give out and usually, the underwires are the first to pop.

You can find your perfect Rose & Thorne bra at hone with our helpful Bra Fit Tools and Bra Sizing Advice, including our Bra Size Calculator and our Bra Size Chart. We are here to help, so feel free to schedule a one-on-one online bra fitting.