In order to perform the test, the doctor will need to see your bowels and rectum clearly, which means you will have to ensure your lower bowel is fully emptied before the test. You will be given either a strong laxative to take at home before your appointment or be given an enema to use at home, which a health professional will give you instructions on how to perform. You will also be asked to eat a light meal the night before the operation to ensure your bowels are as empty as possible for the test.

During the test, you will be asked to lie on your side and the doctor will apply lubricant to the area before examining your rectum with a gloved finger. The doctor will then gently pump air into your back passage to open up the lower bowel to allow them to see more. Next, the doctor will carefully insert the sigmoidoscope. The device has a tiny camera on the end of it which allows the doctor to see the inside of your bowel on a TV screen. As the doctor passes the sigmoidoscope through your bowel, they may ask you to move around slightly to help them see different areas of the bowel more clearly.

You may feel uncomfortable during the test as the air used can cause stomach cramps and the sigmoidoscope itself can make people feel that they need to go to the toilet. The procedure shouldn’t be painful though and usually takes no more than 15 minutes.