Taking low-dose aspirin could slash women's risk of ovarian cancer by a quarter، a major study has concluded، as the Daily Mail said. A study of 205،000 women، led by Harvard University، found those who regularly took a quarter-dose painkiller were far less likely to be diagnosed with the cancer. Ovarian cancer، known as a 'silent killer' because it has few symptoms until too late، affects about 7،400 British women and 22،240 American women every year، and kills 4،100 Brits and 14،070 Americans. The research team found that women who regularly took a low-dose aspirin pill - typically available in the UK in a 75 milligram dose for daily use - were 23 per cent less likely to develop ovarian cancer. The same benefits were not found for a high-dose pill - the 300mg dose used for headaches - possibly because they were not taken long-term. Aspirin has been used as a painkiller for thousands of years، since the Ancient Egyptians found that an extract of willow bark helped mothers cope with the pain of child birth. But in recent years scientists have found that the cheap drug has many more applications. Because it thins the blood and reduces inflammation، scientists are increasingly finding that it can ward off the threat of diseases. The cheap drug، which costs less than 2p per tablet، is commonly prescribed by doctors in lower doses to prevent heart problems، because it stops platelets in the blood clumping together to form clots. Scientists have for some time been exploring whether aspirin may ward off cancer. Experts have already shown that low-dose aspirin could significantly reduce the risk of bowel cancer. But the new Harvard study provides the strongest evidence to date that aspirin may also be used to stop ovarian cancer - the sixth most common cancer among British women. The authors do not know exactly how this works، but they suspect it may be because aspirin reduces platelet activation - a key part of the formation of tumors. The reduction of inflammation - which is specifically linked to the development of ovarian cancer - is also likely to play a role. Researcher Dr Mollie Barnard said: 'What really differentiated this study from prior work was that we were able to analyse low-dose aspirin separately from standard dose aspirin.