I would like to know this as well, and I'm wondering if you can have tattoos over stretch marks since weight lifting gave me some, unfortunately.
Yes, tattoos will strecth with extreme weight gains/loss and for any surgery that stretched skins(ie tummy tucks/face lifts/reconstructive surgery where skin was removed). With normal 5-15 lb weighht fluctuattions it won't be a problem, but if youplan on going on a major diet/hitting the gym hard/or you put on all you weight in one place, I would carefully consider timing and placement. Cheers
During my recent pregnancy I was able to avoid any stretching--I was a bit worried about the tat on my lower tummy, but it was low enough that after the 4/5 months that my tummy was huge, it didn't stretch. That's something you may want to think about too, if you're a lady. Breasts/Tummy tats are most vulnerable to stretching if you ever decide to have children.