Its also worth pointing out that for every man who likes a woman to don a push-up bra in bed, theres another who likes stockings and a third who prefers nudity.

London - Pinched flesh, unsightly bulges and backache - the wrong bra can be misery. But according to a new report, eight out of ten of us are wearing badly-fitting bras because the traditional method of measuring bust size is outdated and just doesn’t work.

According to academics at the University of Portsmouth, using a tape measure to find your bra size is a waste of time because women’s bodies have changed dramatically since the system was invented in the 1930s.

The traditional method of bra-fitting, still used by most shops, involves two measurements: one from under the bust and around the ribcage, and the other from around the fullest part of the bust.

The first measurement gives the back size in inches, and the difference between the two measurements determines cup size (A denotes a difference of one inch, B of two inches and so on).

But according to the academics, this method is hopelessly out of date because it was designed to go only up to a D-cup. Half of women in the UK now exceed that size.

The secret to finding the perfect fit is to take a five-step approach: assessing the length of the straps, the shape of the underwire, how well the back fits, how well the cup fits and whether the front band is in contact with the breastbone.

This doesn’t surprise expert bra fitter Dita Summerfield from Rigby & Peller, underwear fitters to the Queen.

“The huge majority of women coming to us for a fitting are wearing a completely wrong bra size,” she says. “Most wear their bras too loose on the back and too small in the cup. But 80 percent of the support given by a bra comes from the band around the middle - not the straps or the cup - and if it’s loose, you are not getting enough support.

“You get ten percent of your support from shoulder straps, which are often worn too loose, and ten percent of the support from cup size, which so many women wear much too small.”

“Women tend to decide their size and stick to it - they see something pretty and buy it in that size without trying it on. But sizes vary hugely in different shops. You cannot rely on the number on the label to find the perfect fit.”

Five steps to a perfect fit

1. Strap length

You don’t need to adjust your straps to the same length on each side. Many of us have sloping shoulders, perhaps from carrying bags around on one side for years, and so it could be that one strap needs to be tighter than the other.

2. Underwire shape

If you press on the underwire of your bra, it should press on bone, not breast tissue. The underwire should sit on your ribcage, encasing your breasts but not digging into them.

3. Back fit

You should just be able to fit two fingers under the band. It should feel snug - perhaps tighter than you’re used to, but not uncomfortable. If it rides up in the middle of your back, it’s too big and won’t give you enough support.

4. Cup fit

Nine times out of ten, women are wearing too small a cup size. You should not have any breast tissue spilling out the top of the cup - known as “double boob”. The average woman is now a D-cup, yet most think they are a B-cup.

5. Front band

The middle should sit flat against the breastbone. If it’s pulling away, leaving a gap between the middle of the bra and the skin, the cup size is too small. - Daily Mail