GOVERNMENT attempts to reduce high-risk sexual behaviour among teenagers have had exactly the opposite effect, according to an authoritative new study.

Expanding contraceptive services and providing the morning-after pill free to teenagers have encouraged sexual behaviour rather than reducing it, according to economists at Nottingham University.

In a study which throws into question the Government’s entire teenage sexual health strategy, they discovered that sexual activity and sexually transmitted diseases have risen fastest in those areas where the Government’s policy has been most actively pursued.

Critics said that the findings exploded the official line that the best way to tackle rising teenage pregnancy and sexually transmitted infections (STIs) was by making contraception more easily available. Robert Whelan, of the independent think-tank Civitas, said: “The method which the Government’s teenage pregnancy strategy relies upon is almost guaranteed to produce these results. They have always promoted condom use, but have never contemplated the possibility of teaching young people abstinence.”

By making the morning-after pill free to teenagers, the Government had masked real levels of sexual activity among teenagers, he said. Because the pill causes early abortions, some conceptions are never counted in the teenage pregnancy figures. “The morning-after pill may cut pregnancies, but it won’t do anything to decrease STIs. That is why the STI rate is now a much more reliable indicator of sexual activity among young people.”

But proponents of widespread family planning for young people rejected the findings. Anne Weyman, chief executive of the Family Planning Association, said: “The evidence is that in areas other than London, teenage pregnancy rates have fallen by between 8 and 15 per cent since 1998.

“The awareness of sexually transmitted infections is quite low among young people. In the last few years, increased screening has been introduced, particularly aimed at young women, and of course, if you start looking for more infections you will find them.”

She believed that the teenage pregnancy strategy could be improved. “One area where it needs to be greatly strengthened is the provision of sex education to young people,” she said. “We want to see young people delaying having sex until they are able to make responsible decisions. I don’t think this research helps to achieve any of those aims.”

The Government has welcomed falling teenage pregnancy levels. But last month figures showed that after three years of decline, the number of teenagers becoming pregnant increased by 2.2 per cent to 41,868 in 2001-02.

The new study, to be presented today at the Royal Economic Society’s annual conference in Swansea, is based on data collected by 95 health authorities in England between 1998 and 2001. They covered a wide range of indicators of teenage sexual activity and contraception, including teenage pregnancy rates, reported cases of STIs and the number of local family planning sessions. It also took into account factors such as family background, parental employment rates and educational qualifications.

The results show that the areas with the biggest increases in family planning sessions since the introduction of the teenage pregnancy strategy in 1999 have seen greater increases in STI rates than others. A doubling of the clinics in an area led, on average, to a 6 per cent increase in STI rates.

The study also found that the availability of more clinic sessions did not lead to bigger reductions in teenage pregnancy. In some areas, increased clinics were linked with higher pregnancy rates for under-18s.

David Paton, the author of the study, said: “When you introduce policies that seem obvious, it is important to factor in the possibility that the policies may actually cause people to change how they behave. In this case, it appears that some measures aimed at reducing teenage pregnancy rates induced changes in teenage behaviour that were large enough not only to negate the intended impact on conceptions, but to have an adverse impact on another important area of sexual health — sexually transmitted infections.”

The Government had assumed, he said, that adolescent sexual activity was the outcome of random decisions. His findings suggested that adolescents thought rationally about the decision to become sexually active.

So, when the cost of birth control goes down, its use goes up. This was true both for adolescents who were previously having sex and not using birth control and for adolescents who were previously not having sex.

This interpretation is underlined by Professor Paton’s data on the morning-after pill. Areas where the pill was made available free had seen no reduction in teenage pregnancy rates, but STI rates had risen.

“Teenage sexual behaviour appears to be little different to other fields in at least one important respect: incentives matter to teenagers too,” he said.

John Reid, the Health Secretary, said: “We are aware that the number of cases of STIs are rising among younger poeple, and we are not complacent about this. But individuals as well as government have a responsibility to tackle this problem.”

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