Mover Mike

"When I spoke at an annual lecture in her (Marie Stopes, who set up the UK's first family planning clinic in 1918) honour in 1995 I was astounded to find that in those days lemon was a common contraceptive. Then in 2001 I found the acidity kills HIV, and could be developed into a microbicide.
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During his research Prof Short has visited the city of Jos in Nigeria, where prostitutes routinely use lemons both as a contraceptive and to ward off sexual transmitted disease.
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He now plans to try out the theory at a family planning clinic in Thailand, where he has convinced more than 100 people not infected with HIV to have unprotected sex with their partners to test the contraceptive qualities of the fruit.