Women24.com -- "High-tech's playing a growing role in underwear," said the fair's fashion manager Sophie Morin. "Take ultra-sounds for example, now used as well as laser technology to cut and construct garments without seaming or stitching."

Also touted is a range of French lingerie called Milkshake – the fabric is made of milk proteins and contains 10 amino acids to hydrate the skin.

"The knit is as soft as satin," said Morin.

There's also a cupless anti-wrinkle bra, designed by Decollete. Throw it on at bedtime to keep your breasts apart and prevent the formation of feared crinkles that appear in the night.

"I dread to think of my husband's likely reaction if I was to come to bed wearing it," said one blogger on www.truthinaging.com, a site that has already consigned the bra to its "department of daft."

The smart bra from Slovenia's Lisca boasts cups made of memory foam that ebbs and flows with body-heat – a NASA patented technology from the 1960s.

Some 20,000 lingerie types from more than 100 nations are due to attend the end-month Paris fair, bringing together more than 500 brands, including Brazil's LZ, flying in with an ultra-light bra that weighs in at 67 grammes.