A sigmoidoscopy examines the lower part of your colon

A sigmoidoscopy is a diagnostic test to check the lower part of your colon or large intestine (the sigmoid colon). This part of your colon is close to your rectum and anus.

A sigmoidoscopy can help find out why you have:

  • Diarrhea
  • Belly or abdominal pain
  • Constipation
  • Abnormal growths (polyps)
  • Bleeding

A sigmoidoscopy may also be used to take a tissue sample or biopsy. And it can be used to remove polyps or swollen veins in your rectum and anus (hemorrhoids). It is also a screening test for colorectal cancer.

A sigmoidoscopy is done using a thin, flexible tube (a sigmoidoscope). The tube has a tiny light and camera. The tube is put into your anus and moved slowly through your rectum into the lower part of your colon. The tube will blow air into your colon. This will make it swell up a bit, so it is easier to see.

Reasons you might have a sigmoidoscopy

A sigmoidoscopy may be used to see or diagnose certain things in your lower colon such as:

  • Abnormal growths (polyps)
  • Tumors
  • Sores (ulcers)
  • Redness and swelling (inflammation)
  • Swollen veins in your rectum and anus (hemorrhoids)
  • Pouches on your colon wall (diverticula)
  • Narrowing of your lower colon (strictures)

It can also be used to find the cause of recent changes in:

  • Your bowel habits
  • Lower belly (abdominal) pain
  • Itching around your anus
  • Blood or mucus in your stool
  • Low iron levels or low blood count

A sigmoidoscopy is one type of test used to screen for colorectal cancer. Health experts recommend both men and women follow a colorectal cancer screening schedule starting at age 50. Talk with your health care provider about a screening schedule that is best for you. Many options are available to screen for colon cancer.

Your health care provider may have other reasons to recommend a sigmoidoscopy.

To schedule an appointment with a specialist at Main Line Health, call 1.866.CALL.MLH (1.866.225.5654) or use our secure online appointment request form.