What To Expect During Bone Marrow Tests

Bone marrow aspiration and biopsy take about 20 minutes each. Before the test(s), the doctor or nurse will tell you what will happen. Your breathing, heart rate, and pain will be monitored throughout the test.

These tests are generally done on the pelvic bone. Part of this bone is accessible in most people on the lower back. If your doctor uses that part of the pelvic bone, you will lie on your stomach for the test. Aspiration also can be done on the breastbone.

The area on your body where the doctor will insert the needle is cleaned and draped with a cloth. Your doctor sees only the site where the needle is inserted. He or she numbs the skin at the site and then makes a small incision (cut). This makes it easier to insert the needle into the bone. Stitches may be needed to close the cut after the test.

For bone marrow aspiration, your doctor inserts the needle into the marrow and removes a small amount of fluid bone marrow. You may feel a brief, sharp pain. The fluid that's removed from the bone marrow is taken to a lab and studied under a microscope.

If your doctor decides to do a bone marrow biopsy, it's done after the aspiration. For the biopsy, your doctor uses a needle to remove a small amount of the bone marrow tissue. Thin sections of this tissue are studied under a microscope.

During both tests, it's important for you to remain still and as relaxed as possible.