Does being on aspirin already helps against developing dvt?

No: Vein blood clots are not prevented by baby Aspirin that is used more commonly for prevention of arteial or coronary clots.Prevention of dot are being active as stagnation is a key causative factor.

Actually....: There is emerging data that if you have already had a dvt, an Aspirin reduces your risk of recurrent dvt, and i place all my DVT patients on Aspirin for this. There is no data that Aspirin reduces your risk for first DVT however.