A study at the National Cancer Institute (NCI) has shown that women who take aspirin daily may reduce their risk of ovarian cancer by 20%. Prior research has suggested that the anti-inflammatory properties of aspirin and non-aspirin NSAIDs may reduce overall risk of cancer, but studies specific to ovarian cancer have been inconclusive. This is the largest study to date on risk reduction in ovarian cancer and these medications. Britton Trabert, PhD, and Nicolas Wentzensen, MD, PhD, and their colleagues from NCI’s Division of Cancer Epidemiology and Genetics examined data from 12 large epidemiological studies (9 from the US) of nearly 8,000 women with ovarian cancer and close to 12,000 women without ovarian cancer. Eighteen percent reported that they used aspirin, 24% used non-aspirin NSAIDs, and 16% used acetaminophen. Daily aspirin users had a 20% lower risk of ovarian cancer compared to those who took it less than once a week. Women who reported using NSAIDs at least once a week showed a reduction in risk that was not statistically significant, and acetaminophen was not associated with a reduction in ovarian cancer risk.