How to hook a Cosmo girl

A thirtieth birthday is invariably a time to reflect on life's rich journey, and to contemplate the values with which one hopes to ease into middle age. For one 30-year-old, whose birthday falls on Monday, those values are likely to include frequent sex, of all varieties, and a crusade against the missionary position. Cosmopolitan has never been shy of shouting about what matters.

Cosmo has witnessed a few changes in these past three decades. Thankfully, it has thought to document them in all their vivid immediacy: from the early feminist awakenings to the late-Nineties backlash, the magazine's cover lines have faithfully recorded the nation's mood. "There must be four million PhD theses based on our cover lines," explains Deirdre McSharry, editor from 1973 to 1985. "I know, because I saw the students at work in our building."

McSharry and launch editor Joyce Hopkirk had worked together at The Sun, and their tabloid sensitivities were to define a witty new style of magazine tease line. They also learned some Hollywood pizzazz from David Brown, husband of American Cosmo founder Helen Gurley Brown and later the producer of such blockbusters as Jaws.

Gurley Brown's creation proved an instant success in Britain. The first issue, with a print run of 350,000, sold out in 24 hours; the second sold 450,000 in 36 hours. "We were just working out what preoccupied a new generation of young women at a time when wages were rising, job opportunities were growing, and education was improving," McSharry says.

She credits much of the success to the words on the front page. "There was a bit of a formula. We tried to get the word 'sex' on to every cover. For research, I'd take four or five of us to Newcastle, and stand on the station platform to see what jumped out from the various magazines. It was usually Cosmo that won, with words like 'join us', 'win', 'enjoy', 'celebrate'."

The covers succinctly narrate the changing lives of Britain's young women since 1972. Along five walls in National Magazines' Soho headquarters, an almost complete collection of Cosmo front pages tells of a nation gaining ever greater sexual curiosity, redefining gender roles, and empowering women in the workplace. Take sex. From the first issue's bold teases - "Michael Parkinson talks about his vasectomy", above Jilly Cooper on why Roy Jenkins makes a "fantastic lover" - the sexual references become ever more lurid.

Initially, sexual taboos were such that any reference to lovemaking was enough to grab attention. Then along came Alex Comfort's Joy of Sex, and Cosmo felt increasingly comfortable talking about nymphomaniacs, faked orgasms and Paula Yates's sex toys. By the early 1990s, few things could not be said. "Great sex is crazy positions, silly noises, odd odours and other undignified things," stated one cover line.

"We were looking for lines that made you smile," says Marcelle d'Argy Smith, editor between 1990 and 1995. A highlight, she recalls, was the 1991 line: "Read all about it - the 60lb penis." "In fact, it was something I'd got from some nature magazine about a sperm whale. I had readers ringing in furiously to complain."

D'ARGY Smith was not averse to using "oral sex" on cover lines, but felt that "power" did not work in those pre-Spice Girls days. By contrast, Cosmo's current editor, Lorraine Candy, is comfortable with "power", but has banned "shag" and says she will never run a feature on oral sex. "I don't think I'd use the word 'vagina', unless it's very clever or ironic," Candy adds. "I have used 'Penis genius', though I wouldn't use it as the biggest cover line. It's not the readers we have to worry about, it's the supermarkets and WH Smith." London Underground, too, has sought to define the limits of acceptable cover lines. It objected to the words "I was frigid", and demanded that the offending "frigid" be covered by a black strip. Alas, the tape only partially covered the word, leaving some posters saying: "I was f - - d".

Athough sex appears on every cover, Candy is convinced real-life stories are what sell Cosmo. "When we put women's confessions on the front, we know it will be the biggest-selling issue of the year," she says. "I don't think they're buying Cosmo for the 'one-hour orgasm'." Women's vulnerability also sells. "We compiled a list of cover lines after six months of research, and the top 10 were all about personal safety - how to be safe on the streets, avoid being raped, deal with sexual harassment at work. I was surprised. 'Rape' is a big draw for us."