It is not until knickers turn grey and saggy, vests become full of holes and bra straps start fraying that most women decide to invest in some new garments, a study reveals.

Sixty per cent will only ever buy underwear when it needs replacing with just 31 per cent splashing out on bras and pants for special occasions, say market research analysts Mintel.

'Despite the return of saucy Burlesque shows by Dita von Teese and others, British women still take a functional and practical approach to underwear and clearly don't see it as something that can be really sexy and alluring,' says Mintel's senior fashion analyst Katrin Magnussen.