A new contraceptive method could be on the market within five years, Edinburgh University scientists hope. Researchers reported yesterday that a male contraceptive pill developed by the Dutch firm Organon was 100% effective, with no harmful side effects, in recent clinical trials run in Scotland and Shanghai. The pill introduces hormones into the bloodstream that stop the production of sperm, and is the first successful attempt to develop an oral contraceptive method for men. The sperm count of the 60 men who took the pill over a period of months dropped to zero, and none experienced side effects like acne or high blood pressure which have curbed previous attempts at developing a male contraceptive pill. The report was published in Human Reproduction, the journal of the European Society for Human Reproduction and Embryology, and showed that 75% of Scottish, Chinese and white South African women felt that their male partners would use the pill. Even in the more conservative black and mixed-race South African population, 40 percent agreed their partners would probably use it, the New York Post and BBC reported. Complete results of the trials, being conducted in Shanghai, Scotland, South Africa, and Nigeria, will be released this September at the World Conference of Gynecologists and Obstetricians.