I have Masters degree with Distinction and Student of the Year Prize in Corrosion of Engineering Materials from Imperial College London, first degree in Chemistry from University of Central Lancashire and also did Technology, Material Science and Engineering and Mathematics from the Open University.
In areas where tattooing is not as closely monitored, people are asked to wait for 12 months to give blood after getting a tattoo. This waiting period ensures that the donor is free of any potential blood-borne diseases which could have been passed on unsanitary equipment.
In the United States, you must wait 12 months after getting a tattoo or body piercing before donating blood if your state does not regulate tattoo facilities. This is because bloodborne diseases may be spread by needles, and no one has come up with a good way to vet the tattoo and piercing parlors as not re-using needles.