Arabella Weir: Want to know why young girls sleep around? Ask a veteran

Science should be figuring how to graft a condom on to a penis

So there's a new method of contraception on the block and it's looking pretty good - an injection providing its recipient with three years' worth of freedom. One small prick and off you go - on a shag marathon because, of course, indiscriminate shagging round the clock is what women of all ages do the very nanosecond they've secured reliable contraception. Why, you only have to look at contraception's recent history to see how when we're not properly fettered we just take the ball and run.

There's nothing we girls like more than mindless, carefree sex. God forbid that we should be provided with a (second) method of birth control that frees us up to act with a semblance of, dare I say it, male abandon the moment someone tasty puckers up. Those against this new method seem to think it will fuel promiscuity. These critics, I'll be bound, have scant experience of promiscuity, either in the field or as observers. Well, stepping forward, in this instance from the rank of veterans, may I assure them that "handing it out", as it was known in my youth, has precious little to do with contraception - not the difficulty of securing it nor its easy availability.

Promiscuity (for want of a much less pejorative word), particularly for young girls, is motivated by a variety of much more complex issues among which, high on the list and jostling for first place, are lack of emotional maturity, social pressures, desire for popularity, a misguided need to feel loved and wanted, and point-scoring. In all my gossiping years I have never heard a girlfriend tell me she'd had sex with some guy because she'd thought, "Might as well", having discovered the wherewithal not to get pregnant. That's a bloke's thinking - not a woman's.

I am informed that the other voices of dissent are shouting about this injection representing a failure to deal with the root problem behind the UK's high number of teenage pregnancies - again, apparently, the results of promiscuity. I dare say a handful of teenagers did have children as a result of getting knocked up without thinking about it. But I reckon the vast majority get pregnant, and keep their babies, because they imagine being a mum will make them feel special and cared for. And that is why teenage pregnancies are so high in this country - not because they can all boff at will in an inner-city bus shelter, but because we don't value young people properly. We can't do, because if we did, they'd be properly educated by properly paid teachers in properly funded schools, and not charged for the "privilege" of going into higher education.

We don't like kids in restaurants, we don't like boys wearing hoods, we don't like young people hanging around in groups with their trousers half way down their bums. We just don't like young people. We are, after all, the country who came up with "children should be seen and not heard" - try translating that into any other European language and being understood - either socially or actually. All that's happened is that research has discovered another way to liberate us women a tiny bit more (but they still can't work out how to pay us as much as the guys).

The kind of responsible, forward-thinking person who has the presence of mind to get themselves along to a clinic to get an injection is not very likely to be the sort of person who shags someone at a party because he's promised her a lift home. What scientific research really should be concentrating on, however, is figuring out how to graft a condom on to a penis, removable only with written consent from at least two adult women who are not related by blood to its owner. Think of the upside!