I agree with JV to a degree, but there's also an element among the girls of competition that probably hasn't been there forever. I'm 23 next month, and lost my virginity at 19 - very late, as I thought of it at points while growing up.
Perhaps my mum's isolationist child-rearing techniques weren't entirely without merit, because at my all-girls school (which had and has a wide social intake) there was an, admittedly subtle, real status for those girls who had 'done it', whether it be straight sex or oral. Past fifteen or sixteen, around half the girls I knew seemed to be talking about sex and the boys from the all-male grammar in the school.
Sex is a status symbol which is aimed at on both sides of the gender divide, and yet contraception is still seen as something which you don't talk much about unless it goes wrong. A friend of mine, aged fifteen had a mishap and had to be counselled by another friend about taking the morning after pill, because the taboos meant she didn't dare tell her parents about sex.
And that's the other problem. There's a massive perception among a lot of young people that parents and other adult figures regard teenage sex as a taboo, and contraception more so. Whether that taboo actually exists or not is irrelevant, because the kids still won't talk about it.
And that's why a campaign to promote talking about contraception of all types in a non giggly-silly way is just what we need.