Brook Advisory Centres is launching its Roll With It leaflet on Monday as part of National Condom Week.

The leaflet is aimed at young people between the ages of 14 and 16 - particularly boys who often escape family planning information.

Brook says it hopes to raise young people's confidence in using condoms by debunking common myths associated with them.

"Boys often feel they are too tight, they do not feel natural, they are like wearing wellies in the bath and that girls who carry condoms are easy," said Alison Hadley of Brook.

"They need better information."

Vernacular language

The leaflet, which is free from Brook centres and can be purchased by schools and health promotion units, explains in teenage language how to use a condom correctly and why they are necessary.

For example, it explains: "Flavoured condoms are OK for oral sex (blow jobs and sucking off), but if you are going to use them for having sex (shagging or doing it) make sure they have got a kite mark."

Teenagers often feel unconfident about condom use, say experts

The use of terms like "sucking off" have been criticised by family campaigners, such as Victoria Gillick.

She says the leaflet is "dirty and unacceptable", will not reduce teenage pregnancies and should be banned.

But Brook argues that the leaflet has proved effective in tests and that vernacular language is necessary.

"We use the terms young people use. There is a surprising amount of misunderstanding about terms used.

"No-one tells young people and some terms fly around the playground without people understanding what they mean," said Ms Hadley.

The leaflet also shows people how to put on a condom.

Practice makes perfect

Brook says boys should be encouraged to practise on themselves before they have to use a condom for real.

"They can often feel embarrassed and unconfident. They may fumble about and be in a hurry. It is a recipe for disaster," said Ms Hadley.

"If they use condoms incorrectly they can come off or split," she added.

The UK has the highest level of teenage pregnancy in Europe.

Brook says it is estimated that between a third and a fifth of young people have sex before they reach 16.