We're obsessed by sex. Sex sells underwear, perfume, cars and almost anything else you want it to sell. Sex pervades our magazines, newspapers, literature, music and films. The image used to promote Casino Royale is no less steamy for being a damp Bond in swimming trunks emerging from the sea in place of the usual nubile and scantily clad female paramour. Sex is the most powerful force we know.Which is why it's so strange that we can't deal with its fallout. Do Bond girls get syphilis or have abortions? No one wants to know. We like our sex erotic and exciting and free from disease and reproductive consequences. This is fantasy sex. Perhaps it should come with a health warning: the real thing can damage your life.
In enlightened Britain, where we think we are so praiseworthily open about sex, we have the highest rate of teenage pregnancies in Europe and rising rates of sexually transmitted disease. The Department of Health has just launched a campaign to "normalise" condom use among young people. All power to it, but there wasn't much evidence that girls and boys were slipping condoms into their pockets before a night out after the last campaign two years ago. It may be the right road, but we've got a long way to travel along it.
If we can't sort out our own problems we're in a poor position to moralise about those in other countries whose lives are far, far more difficult than ours. Yet how many of us secretly think that Africans have brought the devastation that Aids is doing to their countries upon themselves? There is a tacit assumption that Africans sleep around, that they are sexually abandoned and that they are reaping what they sowed.
But a courageous series on sexual and reproductive health, currently running over six weeks in the Lancet medical journal, proves that wrong. The papers show that we are more promiscuous than Africans. We in the rich world have more sexual partners than they in that benighted, disease-ridden continent. We have recreational sex; they are too busy trying to survive.
The consequences of such moral superiority are grave - not only in the fight against Aids but across the whole field of sexual and reproductive health. We have the US preaching abstinence from sex as the answer to Aids in Africa and refusing funds to any family-planning clinics across the world that provide abortions or even counsel women about them. This head-in-the-sand attitude towards abortion leads directly to women's deaths. Every year nearly 20 million unsafe abortions are carried out on desperate women in ill-lit rooms and illegal clinics. You don't stop that happening by refusing to talk about it.
It is extraordinary that not only unsafe abortion but sexually transmitted diseases are so controversial. One of the Lancet authors had to withdraw her name from a paper. Her employer, the US Centres for Disease Control and Prevention, one of the world's leading public-health bodies, considered that the journal had strayed too far over the political boundary.
Who knows how much else has not been written or done because of transatlantic pressures? The US government cut off all its $2.5m funding for the World Health Organisation's department of reproductive health and research in 2002, at roughly the same time that it cancelled its $34m funding of the UN's population fund, the UNFPA, which says women have a human right to contraception and reproductive health.
The US is not alone in blocking progress. At the UN general assembly special session on children in 2002, the US was part of a curious axis with Iran, Iraq, Libya, Sudan and the Vatican (which now appears to be considering a seismic shift to condone the use of condoms in Aids-hit countries) in agitating for redefinition of the phrase "reproductive health services" to exclude abortion. To our government's credit, on the other hand, Britain has publicly taken an unusual and impressive stand against the US on abortion and sexual health in developing countries.
Many think the US is a lost cause as long as President Bush is in office. It is up to Europe, led by Britain, to try to undo the damage. Safe abortion is vital, but the less controversial - yet apparently morally distasteful - problems of infections such as syphilis, gonorrhoea and chlamydia need to be tackled because they are physically and socially damaging, particularly to women, and easily treatable. There is also a desperate need to address the issue of making pregnancy and childbirth safer: around 210 million women suffer life-threatening complications each year.
These things, just like unmentionable diseases, have to do with the dark side of sex, and those who suffer most are women - impoverished, low-status, voiceless women. It's time we really talked about sex. This is going to be a hard fight, but it's one we should be proud to take on.
Sarah Boseley, the Guardian's health editor.