The government is to launch a hard-hitting TV campaign to encourage young people to use condoms to combat the rise in teen pregnancies that occurs during the booze-fuelled Christmas party season.

In the TV ad a pair of teenage partygoers consume a large amount of alcohol and have sex, with the girl getting pregnant.

However, the commercial, developed by the ad agency DLKW, runs backwards, starting with the distraught girl testing positive with a pregnancy test and rewinding through a night out, including the downing of shots and vomiting on a plant.

The ad, which targets 16- to 18-year-olds, is part of the government's "Want Respect? Use a Condom" campaign and is based on research suggesting that young people are twice as likely to have unprotected sex when drunk than when sober.

"It's at this time of year, the Christmas party season, when we need to get across to young people the dangers of unprotected sex," said the young people's minister, Beverley Hughes.

"This new TV ad shows how one drunken night can lead to an unplanned teenage pregnancy," Hughes added.

The TV ad will run on satellite channels from tonight.

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