Hello Berley Kay, I had 14 biopsies a couple of months ago. It was by far the most I have ever had taken. Days later I had severe rectal bleeding which I blamed on the biopsies. 4 days later it was confirmed as a perforated bowel caused by one of the biopsies, I had blood transfusions and surgery. I felt 14 had been too many but my IBD nurse said there was a formula which was (X amount of biosies per centimetre of affected bowel) Needless to say I will be nervous of biopsies at my next colonoscopy. Regardless of the formula the 14 seemed excessive but I was offered an explanation and I'm sure you will be too. I don't feel so bad about mine knowing that you had 18!