Health Encyclopedia

Bone Marrow Aspiration and Biopsy

Does this test have other names?

Bone marrow exam

What is this test?

This is a two-part test that looks at the blood cells in a sample of bone marrow, the spongy tissue within certain bones. This test may help your healthcare provider diagnose or monitor a blood disease or health condition affecting your marrow.

Your bone marrow has a liquid part and a solid part. Aspiration uses a needle to remove a sample of the liquid part of bone marrow. Biopsy uses a larger needle to remove a small amount of bone with its marrow.

Part of the job of bone marrow is to make blood cells. This test can find out how well your bone marrow is working. This test is also done to find some types of cancer.

Why do I need this test?

You might have this test if your healthcare provider wants to find out the health of your bone marrow or to check on how well your marrow is making blood cells.

You may have an aspiration to check for:

  • The health of your bone marrow for a transplant

  • Acute leukemia

  • Multiple myeloma

In some cases, bone marrow aspiration is used to confirm chromosome disorders in newborns.

You may have an aspiration followed by a biopsy if you could have:

  • Bacterial, fungal, or parasitic infection

  • Unexplained anemia, leucopenia, or thrombocytopenia

  • Metastatic cancer or many other diseases

What other tests might I have along with this test?

Your healthcare provider may also order these tests:

  • Complete blood count, or CBC

  • Reticulocyte count to find out your red blood cell survival rate

What do my test results mean?

Many things may affect your lab test results. These include the method each lab uses to do the test. Even if your test results are different from the normal value, you may not have a problem. To learn what the results mean for you, talk with your healthcare provider.

The lab will look at different aspects of your bone marrow to help find certain diseases or conditions. These aspects include:

  • Type and number of blood cells

  • Any abnormalities in the size, shape, or look of cells

  • Level of iron in the bone marrow

  • Abnormal amount of young white blood cells, called blasts

  • Any chromosomal abnormalities

Depending on what is seen, your results may mean you have an infection, a blood disease, leukemia, or cancer that has spread to the bone marrow from another site.

Your healthcare provider will take your results and combine this information with information from your physical exam, health history, and other types of tests to make a diagnosis. 

If your results are negative, your provider may order other tests to diagnose your condition. 

How is this test done?

These tests require a sample of bone marrow. A number of sites on your body can be used for marrow aspiration, but the hip bone is a common spot. You will likely lie on your side or stomach on an exam table. Your healthcare provider will numb the area of the test. You may feel a slight prick from the needle that the provider uses to give the numbing agent.

Does this test pose any risks?

It's not possible to numb the bone, so you may feel slight pain during the procedure. But you shouldn't feel any pain afterward. Risks from a bone marrow test are rare, but you could have bleeding or an infection.

What might affect my test results?

Other factors aren't likely to affect your results.

How do I get ready for this test?

Tell your healthcare provider if you take aspirin or have any allergies. Also tell your provider if you are pregnant, take any blood-thinner medicines, or have a history of bleeding problems.

Be sure your provider knows about all other medicines, herbs, vitamins, and supplements you are taking. This includes medicines that don't need a prescription and any illicit drugs you may use.


Medical Reviewers:

  • Fraser, Marianne, MSN, RN
  • Sather, Rita, RN