YOUNG women in Scotland are the least likely in Britain to be tested for the UK's most prevalent sexual disease, new figures show.

One in three sexually active females aged 16-24 north of the Border were tested for chlamydia, according to the latest British sexual health survey.

The figure compared with around one in two young women in Wales and almost 60% of young women in England who were checked.

The figures are published today in the Lancet and were gathered as part of the third National Survey of Sexual Attitudes and Lifestyles (Natsal) survey.

The contrasting attitudes to testing for the disease have been blamed on differing screening strategies between the nations.

England is running national screening programmes which urge all sexually active under-25s to undergo a free test for the infection once a year or whenever they change partners.

The introduction of the ­screening programme in England ten years ago resulted in a 76% surge in the number of young people being tested for chlamydia at their GP practice, and a 40% increase in diagnoses.

In Scotland, chlamydia testing is targeted to under-25s "opportunistically", for example if they visit their local sexual health clinic, but there is no chlamydia-specific testing drive.

Chlamydia is the most common sexually transmitted infection. In 2010, the most recent year for which Scottish figures are available, it was diagnosed in one in 10 young women and one in seven young men who took the test.

Gordon Macdonald, ­parliamentary officer at Care for Scotland, which has campaigned to promote abstinence among young people, said: "Scotland's sexual health policy is failing young people. We need a radically different approach focusing on the benefits of stable relationships and delaying sexual activity.

"Care's relationship and sex education programme, 'evaluate', aims to support young people to have the self-confidence and knowledge to make informed choices as they grow up."

If left undetected, chlamydia can lead to infertility. However, it is often only identified through routine check-ups as ­three-quarters of female carriers of the infection will not experience any symptoms, and only around half of men show signs of infection.

In women, symptoms can include bleeding, abdominal pain or burning sensations when they urinate, while men might experience pain in their testicles or a discharge from their penis.

The Natsal figures also ­illustrated that young males were even less likely to be checked for the infection, with just 22% of yong men aged 16-24 in Scotland turning up for chlamydia test last year.

This compared to 37% in England, but was higher than the rate in Wales, where just 13% of young men were tested last year.

More than 15,000 adults aged 16-74 participated in interviews between September 2010 and August 2012.

The survey, which is published every 10 years, aims to give a snapshot of the Britain's sexual health and habits.

A Scottish Government ­spokesman said: "We will be considering the results of the Natsal survey and what they tell us about sexual health and wellbeing in Scotland.

"We are working with NHS Boards to prevent, test and treat all STIs.

"The UK countries have ­different approaches to screening for chlamydia, for example in Scotland there is an opportunistic approach to testing. For this reason it is not possible to directly compare levels of chlamydia testing."