The Public Health Laboratory Service (PHLS) says figures for England and Wales show that sexual health among teenagers was improving in the early 1990s.

But since the mid-1990s, it has got progressively worse.

The long-term effects include cervical cancer, infertility and increased susceptibility to HIV.

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Statistics for sexually transmitted disease clinics in 1995 show that 1,024 teenage girls aged between 16 and 19 had contracted gonorrhoea.

Some 4,940 had chlamydia, 1,622 had suffered their first attack of genital herpes and 6,737 had their first attack of genital warts.

The figures for boys were considerably lower.

Consistent pattern

However, by 1996 the numbers had shot up:

• Gonorroheoa was up 34.5% for girls and 31.2% for boys
• Chlamydia was up 16.5% for girls and 17.9% for boys
• Genital herpes (first attack) had risen by 1.5% for girls, but fallen by 2.5% for boys
• Genital warts (first attack) was up 12.2% for girls and 12.8% for boys.

Teenage abortions were up 12.5% and pregnancies were up 4.6% in the same age group.

Writing in the British Medical Journal (BMJ), the researchers say the increases in abortions and pregnancy took place in every health region.

The rise in gonorrhoea, identified as a marker for trends in sexual behaviour, was found in every health region except Anglia and Oxford.

The PHLS says 1997 figures show a similar upward trend. Statistics for 1998 are not yet available.

Targeted campaigns

But a spokesman said there was some room for optimism. The USA has worse teenage pregnancy rates than the UK, but has recently shown improvements due to targeted education campaigns.

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"They have made a real concerted effort concerning sex education and have targeted young people."

Some ideas, which are thought to have been considered by the government's social exclusion unit in its forthcoming report on teenage pregnancy, include sex counselling by older teenagers.

Mike Catchpole, one of the report's authors, said other European countries had seen rises in sexually transmitted diseases among teenagers, but Britain's was dramatic.

Sweden had done particularly well in keeping a rein on chlamydia, he said.

This was because of education and the targeting of young people through youth clinics.

Dr Angus Nicol of the PHLS says the findings are unsurprising

"Targeted intervention is the key to success," he said.

He added that people who had sex very young were the least likely to use a condom. This meant special efforts should be made to target young teenagers with sex education, he said.

Wild teens

The PHLS says it is pleased with government efforts to give a joined-up approach to teenage sexual health.

Britain has the highest teenage pregnancy levels in the EU

But, in a linked editorial in the BMJ, Professor Martin McKee, Professor of European Public Health at the London School of Hygiene and Tropical Medicine, says the statistics on teenage sexual health could be part of "a more fundamental malaise".

They combine with increases in smoking, drinking and drug use, he says, and show the need for a coordinated policy on improving education and parenting for young people.

Britain has the highest rate of illegal drug use in the European Union, and high levels of alcohol consumption and smoking.

Professor McKee thinks poor rates of literacy, numeracy and basic skills among young people in Britain could be partly to blame.

And he says many more families live in poverty in the UK, with the gap between rich and poor growing "markedly" in the last 20 years.

He adds that another factor could be that British parents spend less time with their children because of overwork.

Britain has the longest working hours in Europe.

He believes the government's approach up to now has been to deal with each issue individually.

But he welcomed the social exclusion unit's report and the government's willingness to learn from other European countries.