It may not be one of the usual reasons why parents encourage their daughters to join the Guides. But this year the skills taught by the movement will be extended from first aid and camping to include problems of sex.

About 450 Guides are to be trained as “peer educators” to run sessions covering sex, contraception, abortion and abuse, as well as alcoholism, stress, bullying and compulsive eating.

The programme, titled Get Wise, has been produced in response to pressure from the organisation’s 600,000 members, who say that they are inadequately prepared by their schools and parents to deal with some of the most sensitive challenges of modern life.

Guide leaders are being advised that there is no reason why a girl should stop being a member if she becomes pregnant, and that the leaders should not intervene too quickly if they think a girl is in an inappropriate relationship.

Get Wise will cover Guides, aged 10 to 14, as well as the movement’s Senior Section for young women aged 14 to 25. Although sessions will be led by a members of the same age group, an adult leader will be present and parents will be informed in advance of topics to be covered.

Denise King, chief executive of Girlguiding UK, said: “There is no point pretending that all of these things don’t happen to Girl Guides and that they all wear white knee socks.

“We are part of society, not apart from it. Girl Guides aren’t the goody-goodies any more. They are just the regular young women of the day. They have told us that these are the issues that are relevant to their lives.”

The education sessions are not about telling the girls not to have under-age sex or not to drink, she said. “We are trying to support the girls and young women to find things out for themselves. We want to give them the confidence to make decisions for themselves and to withstand pressure when they don’t want it.”

The trained girls will tour Guide units, schools and community groups, using role-play, “scenario planning”, debate and true or false games to cover the topics. To help the Guide leaders, the organisation has produced a set of information known as Reality Checks. The one on sex and relationships advises: “What you consider to be an inappropriate relationship may not be inappropriate to others. If the girl is happy and healthy in this it is not your place to intrude.”

Vicky Willis, who is chairing the programme, said that there was a clear need for it. “An issue like sexual health is very prevalent in the media and as our members get older they are affected more and more. Yet it’s something that a lot of our older members feel have not been covered well elsewhere.”

As the country’s biggest “girls-only network”, the Guides are well placed to broach even the most delicate of subjects. Ms King believes. “Because we are all women, it’s a very safe place and the girls feel they can be who they want to be. It is easier to discuss issues like this when you are alongside someone your age.”

Jessica Carmichael, 17, a peer educator from Glasgow, agreed. “It’s very different from talking to your school or your parents. We give girls the opportunity to explore their own views. It’s a very different way of learning than being dictated to.

“We will never say, you should not have sex until you are married, because if a Guide is going to do it, then she’s going to do it anyway. What we will do is ask girls what they think about it and tell them about being safe if they are going to do it.”

Girlguiding UK has undergone several image updates over the past century in response to changing trends. In 1910 members were awarded badges for milking cows and learning to iron, and there was criticism that young women were being encouraged to go camping and play sports.

Today’s members are taught business and industry skills.

Ms King believes that constant efforts to renew the movement through programmes such as Get Wise will help it to remain relevant to young women from all backgrounds.

The movement

The movement has a 50,000 waiting list owing to a shortage of adult volunteers. In some areas, parents put down their daughters’ names at birth

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