If you can't take hormone-containing IUDs, it sounds like you might have to try something completely different because I think the non-hormonal IUDs are prone to cause increased bleeding. Have you talked with your doctor about the birth control ring? It's similar to birth control pills, but because it is places in the vagina, the hormones don't wind up being quite as systemic as they are with the pill. I'm not sure about how it interacts with endometriosis, but you might ask about that one. Good luck!