Birth control placebo

I have to take birth control for my endometriosis. If I don't, I'm in such agony that I literally can do nothing but scream, cry, and vomit. I have a couple of friends with the same condition and they don't take the last four placebo pills in their birth control. They skip those and just continue to the next month. This causes them too no longer have periods at all. It sounds dangerous to the body. I'm just wondering if anyone out there knows any health risks that could be caused by doing this? It'd be nice to not worry about having periods since I'm infertile anyway. But I don't want to risk hurting my body. Please and thank you.