Teenagers are being taught sex education so badly in schools that many are left in complete ignorance about how to avoid sexually transmitted infections and pregnancy.

A letter to The Times today from leading children’s organisations, sexual health experts and eight members of the Commons Health Select Committee, calls on the Government to make relationship teaching a statutory part of the national curriculum.

The experts say that research published today highlights the longstanding failure of schools and how it is contributing to the country’s sexual health crisis.

Of more than 20,000 teenagers in England questioned about sex education, more than half rated the teaching in school as poor, very poor or merely average. Only a quarter said that it was good.

Nearly half of those surveyed by the UK Youth Parliament said that they had never been taught about the effects of teenage pregnancy and would not know where to find their local sexual health clinic. More than half (55 per cent) of all 12 to 15-year-olds, and 57 per cent of girls between the ages of 16 to 17 had not been taught how to use a condom, despite the Government’s recommendations, published seven years ago, that this should be taught in all schools. The majority of pupils over the age of 17 reported not having received any information about personal relationships at school.

The letter, signed by the chief executives of the NSPCC, the Brook pregnancy advisory service, the Family Planning Association and the Terrence Higgins Trust, states: “These figures may go some way to explaining disproportionately high rates of teenage pregnancy and sexually transmitted infections in this country.”

Figures from the Health Protection Agency reveal that among 16 to 19-year-olds, diagnoses of herpes rose by 13 per cent and those of genital warts increased by 6 per cent between 2005 and last year. Government figures also show that the UK still has the highest levels of teenage pregnancy in Western Europe. For every 1,000 births between 2000 and 2005, 27 were to under-19s. It was just eight in France.

The Youth Parliament is calling for sexand relationship courses to be made a statutory part of personal, social and health and economic education. At present sex education is a statutory part only of the science curriculum for 11 to 14-year-olds.

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