Hummingbird, I'm on low dose (100mg) aspirin. Whilst it is safe in most situations, I believe there are some specific situations where it can cause problems, so it's best to do it under medical supervision. I've only ever taken it during cycles on doctor's orders. Chances are, if you ask your Dr about it, they'll give their approval. This cycle I'm not only taking the aspirin, I'm also on clexane, prednisone and feldene (but just since O for that one), not to mention a heap of supplements. Lol, and I'm doing both pessaries and pregnyl for luteal support! We're throwing everything but the kitchen sink at it with our new FS. Our previous FS didn't believe in any of it, aside from the aspirin.