As for the internal bleeding risks. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2036.2006.03077.x/full http://onlinelibrary.wiley.com/doi/10.1111/j.1365-

As for the internal bleeding risks. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2036.2006.03077.x/full http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2036.2006.... "These results translate into an absolute rate increase with aspirin above placebo (the incidence of cases of major GI bleeding attributable to low-dose aspirin) of 0.12% per year (95% CI: 0.070.19% per year).[20] Based on this value, 833 patients (95% CI: 5261429 patients) would need to be treated with low-dose aspirin instead of placebo to cause one major GI bleeding episode during a 1-year period (i.e. the NNH is 833)"