I'll quite happily admit that I will NOT get tattoos because I'm scared shitless of the needle.. However I've gone with many friends to get theirs... I have a friend who has a vine that wraps around her entire body.
I used to do piercing though and that doesn't make me squeamish.. I just couldn't do it to myself
However, I will admit that I had two children by c-section, and you have to be pretty fucking bad to do that shit :P Most people with tattoos would faint at the first contraction, or being awake while people are doing surgery on your body.. feeling hands and whatnot moving your internal organs around is NOT something that's easy to deal with.