I've had my scopes whenever I have a flare or switch doctors. Don't think at regular intervals. At the support group meeting last week the Doctors were saying that after ~10 years of having UC you are at an elevated risk for colon cancer so at that point every 1-2 years is recommended for scopes. can't wait
Maybe you could ask a 2nd doctor for an opinion? If you have insurance, not a bad idea to "check things out"