Hi, I have been diagnosed with stage four endo with bowel involvement , I'm due for surgery within the next six weeks after a long and differcult road to being diagnosed. I first went to the doctors well over 18months ago due to chronic pain and constipation around the week befor and after my period, I also pass a lot of blood from my bowel during this time, the pain is horrendous and I no longer work. My question is that I went for a colonoscopy last spring and they could not see where the bleeding was coming from, I did not know for certain that I had endo at that time. The MRI scan later showed definite bowel involvement so I can't understand why they didn't see it during the colonoscopy. If anyone has had a similar prob I'd be grateful of some advise !