What Causes Vaginal Bleeding After Colonoscopy?

Can one have vaginal bleeding after colonoscopy? The bleeding as if blood from a fresh cut occurs only after a bowel movement - the period date is due but there are no period symptoms the whole day apart from when the BM occurs. A colon polyp was removed during the colonoscopy. Concern is that red blood comes only after a BM and not afterwards for the whole day. This is day 2 of the periods. Age is 38, height is feet 2 inches and weight is 140 lbs