Going bust

Cleavages have been thrusing at us from all quarters since Eva's gentle curves were coerced into a Wonderbra and brandished alongside the provocative slogans.

Never before had sex been used so blatantly to sell lingerie. Flick through an old magazine and you might spot a model looking coy behind her padded bosoms, but it was unimaginable to see one who was openly challenging people to respond.

And respond they have. The UK brassiere trade is now worth around pounds 480 million a year, an increase of 40 per cent since 1991. In particular, demand for underwired designs has swelled to 60 per cent of the market. This means that beneath most of the sensible blouses and jumpers passing by you every day, there will be breasts trained to say, "Hello Boys".

The original Wonderbra was designed in Canada in 1964 and arrived in Britain four years later - thus narrowly missing being burnt by feminists.

For 25 years it was Gossard's baby, staying pretty much the same while sports bras, teen bras, seamless bras and other styles grew up around it. But then, in 1993, the company lost the copyright to manufacture it to Playtex, who set about recreating its image. In response, Gossard launched its nearly identical Ultrabra and between them, the two companies spent pounds 3.4 million in advertising. Then everyone, even M&S, came up with their own "push up and plunge" versions.

Compared with the first bra, invented in 1913 by New York socialite Mary Jacobs who improvised with two small hankies and a length of ribbon and then patented the idea, the cantilevered design is a feat of engineering.

Of the 1.5 million Wonderbras sold every year, 30,000 are assembled each week at the Playtex factory in Port Glasgow. Each garment consists of 46 pieces which take a worker an average of 19 minutes to sew together. The factory used to have more of a conveyor belt approach, but says its employees find it more satisfying to be wholly responsible for each item.

And the Wonderbra phenomenon has given rise to a good deal of social commentary. It's been suggested that there is a correlation between high divorce rates and bra sales - with divorcees heading for the lingerie departments to fight off competition from younger, firmer busts. There's also the notion that the feel-good factor is encouraging women to flaunt it if they've got it - and get it if they don't. Or, confusingly, that it is a sign of a reversal in emancipation. The last time cleavages were big was during the Fifties when, having earned respect for their war effort, women were told to go back home and be feminine again. Augmentation was the only answer.

So, what of the future? According to market analyst Mintel, underwired bra sales have now peaked. And as for Ms Herzigova, she has already set out to prove she has more up top than her 36B bust measurement might suggest