I've read and see a couple of things recently about sex education in schools. One piece was about how progressive teaching methods have failed, according to a recent paper in the BMJ which found that one particular programme actually appeared to raise teen pregnancy rates (or, that the pregnancy rate in the treatment group was significantly higher than that in the control group). I haven't read the paper, but I also haven't read any particular methodological criticisms of it, so I will continue on the assumption that it is a valid contribution to the debate.

There was also a debate on The Wright Stuff yesterday morning about a new form of sex ed which emphasised more positive messages ("Sex is fun", "Sex is good for your health") rather than the more typical negative messages ("Sex will kill you dead if you do it wrong"). The argument made for this trial scheme was that if sex was seen as something to be enjoyed rather than something to be worried about, children would be less susceptible to peer pressure, and would wait rather than just try to get it over with as soon as possible. I'm not sure I get the logic exactly, nor the necessity of pointing out how much fun sex is, but I'm wouldn't write it off out of hand.

The main point I wanted to make, which I think is being missed in this debate is this: when did the goals become preventing young people having sex and reducing teen pregancy? The actual goal should be preventing the spread of sexually transmitted disease, and reducing unwanted pregnancy. Those are the actual social ills, and the only way to combat them is by education, in quantities great enough for everyone to know exactly what could happen if you have sex, including the exact medical risks, financial issues resulting from unexpected pregnancy and legal matters than may arise from negligent parenting.

If, as the critics say, sex education programmes expose more children to the idea of sex (which seems unlikely in given the high sexualised multimedia world we live in) and ends up encouraging more young people to have sex or get pregnant, then this really isn't a problem. Providing those people are fully informed about what they are doing, they have the right to make their own decisions, and the real concern for a government should be making sure everyone is able to make the decisions that are best for themselves.

And why does becoming twenty years old necessarily make your pregnancy better for society? I'm sure there are sixteen year olds who could be better parents than some thirty year olds. Age isn't particularly important, unwantedness is. If you are old enough to fully comprehend a pregnancy and all its implications, then that's enough to take age out of the equation. Would it be better for society if teenagers stayed in school and developed skills and contributed more to the economy? Maybe. But that isn't a decision a government should be involved in. After all, a fully informed person can choose which path makes him or her better off, and such decisions don't just reflect monetary rewards from economic input.

As for society, there are a couple of issues. Let's suppose greater sex education leads to more teen pregnancies, but that these pregnancies are (in general) wanted. It's not clear to me that more children with dedicated parents would do more harm to society than less children, but those who are born are much more likely to be the result of an uninformed mistake. Yes, children create costs for the government through the payment of benefits. But arguing that sex education policy should be designed to minimise the demands placed on the welfare state is ridiculous - if there's a problem with the the benefits system, reform the benefit system. If you think that the benefit system creates distortionary incentives for childbearing over work or further education, then the indirect solution of designing sex education policy to counter this is clearly inferior to changing the incentives directly.

And, on a related point, the dependency ratio (retirees to workers) in the UK is projected to exceed 40% by 2050. It shouldn't inform policy on sex education, but it does help to remember that an ageing population also creates massive problems, and that there could be some benefits to increasing the population at the other end.