Bone Marrow Aspiration and Biopsy

Approved by the Cancer.Net Editorial Board, 07/2023

During cancer care, doctors may collect a sample of a patient's bone marrow to see how well these cells develop and work. This testing is called a bone marrow aspiration or a bone marrow biopsy. It can be done to diagnose some types of cancer, learn more about a diagnosis, or monitor cancer treatment.

Bone marrow is the spongy, fatty tissue inside your body's larger bones. It has liquid and solid parts.

Bone marrow makes these types of blood cells:

  • Red blood cells carry oxygen to all parts of the body.

  • White blood cells help the body fight infection and disease.

  • Platelets help the blood clot and control bleeding.

This article is an overview of what to expect during a bone marrow aspiration and bone marrow biopsy. Learn more about other types of tests and procedures used to diagnose cancer.

Why do I need a bone marrow aspiration and bone marrow biopsy?

A bone marrow aspiration or bone marrow biopsy can diagnose:

  • Blood cancers, including leukemia, lymphoma, or multiple myeloma

  • A fever with an unknown cause

  • Stem cell disorders

  • Rare genetic diseases

Doctors also use the results from these procedures to better understand a blood cancer, including its subtype and stage, determine how well a treatment is working, and monitor side effects of chemotherapy.

What is a bone marrow aspiration and biopsy?

A bone marrow aspiration and biopsy are 2 procedures that are often done at the same time to examine the bone marrow. Together, these procedures may be known as a bone marrow examination. Your doctor will decide if you need 1 or both procedures.

  • Bone marrow aspiration is a procedure that removes a sample of the liquid portion of bone marrow.

  • A bone marrow biopsy removes a small, solid piece of bone marrow.

In both procedures, the doctor usually takes the bone marrow sample from your pelvic bone. This bone is in your lower back by your hip.

Who does a bone marrow aspiration and biopsy?

There are several health care professionals who could do your bone marrow aspiration and biopsy:

  • An oncologist, which is a doctor who specializes in treating cancer

  • A hematologist, which is a doctor who specializes in treating blood disorders, including blood cancers

  • An advanced practice provider, such as a nurse practitioner or physician assistant

A bone marrow aspiration and biopsy can be done at a hospital, clinic or doctor's office.

Who analyzes the bone marrow sample?

After the sample is collected, a doctor who specializes in interpreting laboratory tests will look at the bone marrow cells under a microscope. This doctor is called a pathologist. The pathologist then gives the results to your doctor in a pathology report.

How can I get ready for a bone marrow aspiration and biopsy?

When you schedule your bone marrow aspiration and biopsy, your health care team will tell you how to prepare.

Can I eat or drink before the procedure? You can usually eat or drink normally before the test. Ask your health care team ahead of time to make sure.

Can I take my normal medications? You may not be able to take certain medications, such as blood thinners, before your procedure. Tell your health care team about all medications and supplements you take. Ask whether you should take them on the day of the procedure. If you need to stop your normal medications, ask when you can start taking them again.

Will my insurance cover the cost of the bone marrow aspiration and biopsy? If you are concerned about the costs of your bone marrow aspiration and biopsy, contact your insurance company beforehand to know what they will cover. Ask how much of the cost you will have to pay.

What information will my health care team need? Before the procedure, be sure to talk to your health care team about your medical history and any concerns that you may have. These include:

  • All medications and supplements you are taking

  • Any other medical problems you have, such as diabetes

  • Any drug or food allergies you have

  • Any concerns you have about the test

Before the procedure begins, the health care team will ask you to sign a consent form. This form states that you understand the benefits and risks of the bone marrow aspiration and biopsy and that you agree to have it. This is also another time you can talk to your health care team about any concerns you have.

What should I expect during a bone marrow aspiration and biopsy?

The 2 procedures done together take about 30 minutes. You will receive a medication to block pain during the procedure. Most of the time, people receive a type of anesthesia called a local anesthetic. This is given as an injection (shot) and makes the area for the procedure numb. The medication will block most of the pain of the procedure, and you will be awake and alert.

Your doctor may also recommend conscious sedation, also called twilight sedation. This is given in addition to local anesthetic. Conscious sedation uses pain relievers and sedatives. With conscious sedation, you will stay awake, but feel no pain. It may make you feel drowsy and you will have little to no memory of the procedure.

You may also have the option to take medication before the procedure to help you relax. Talk to your health care team if you have ever had an allergic reaction to anesthesia or if you are nervous.

During the procedure, if the sample will come from your pelvic bone, you will lie on your abdomen or side of an exam table. A medical specialist will clean the skin around the bone with an antiseptic solution. Then, the specialist injects the local anesthetic through the skin with a small needle. The medicine will go into the tissue next to the bone. You will feel a slight stinging sensation. Then the area will go numb.

If you need both procedures, bone marrow aspiration usually comes first.

During a bone marrow aspiration:

  • A doctor inserts a hollow needle into the numbed area and pushes gently into the bone.

  • They remove the center portion of the hollow needle and attach a syringe to the needle.

  • The syringe withdraws the liquid portion of the bone marrow.

  • You may feel a deep, dull, aching pain for a few seconds, similar to a toothache. It may help to squeeze a pillow or someone's hand. When the needle comes out, the pain goes away.

During a bone marrow biopsy:

  • A doctor inserts a larger needle into the same area.

  • They will guide the needle into the bone and rotate it to remove a sample of tissue.

  • You may feel pain and pressure as the needle moves into the bone.

  • The medical specialist will then remove the entire needle.

  • Next, they will place a bandage over the site to prevent bleeding.

What happens after a bone marrow aspiration and biopsy?

If your procedure takes place at a clinic and you only had local anesthetic, you can go home shortly after.

If you received sedation, you will first need to lie down for about 20 minutes. That way the medicine’s effects can wear off. You will also need a ride home after sedation. Be sure to make transportation arrangements before the procedure.

What can I expect after returning home?

Once you are home, follow your health care team's instructions exactly. Keep the area around the bandage clean and dry. Only remove it when instructed. Do not shower or bathe until your health care team says you can.

You will likely see some blood on the bandage dressing. This is normal. You can then cover the wound with a bandage until it fully heals.

You may feel discomfort at the needle insertion site. This can last for several days, especially when bending over. Some people may also feel pain down the back of their leg. Mild bruising is normal. It can show up several days after the procedure.

Watch for signs of an infection after the procedure. Tell your doctor if you have:

  • Fever of 101 degrees Fahrenheit/38.3 degrees Celsius or higher

  • Bleeding that does not stop easily

  • Unusual discharge or severe pain at the needle insertion site

  • Any other signs or symptoms of infection

  • Severe pain in the back or abdomen

Questions to ask about a bone marrow aspiration and bone marrow biopsy

Consider asking these questions before you have a bone marrow aspiration or bone marrow biopsy:

  • Who will do the procedure?

  • What will happen during my procedure?

  • How long will the procedure take?

  • What are the risks and benefits of having the procedure?

  • Will I be awake or asleep during the procedure?

  • Will I feel any pain during the procedure? If so, for how long?

  • How can reduce the pain?

  • Can I take my usual medications the day of this procedure? If not, when can I restart my medications?

  • Will I need to avoid any activities after the procedure? If so, how long?

  • How should I care for the wound at home?

  • When will I learn the test's results?

  • Who will explain the results to me?

  • Could I need more tests if the results suggest cancer?

Related Resources


What Is A Bone Marrow Transplant (Stem Cell Transplant)?

Donating Bone Marrow Is Easy and Important: Here’s Why

More Information

MedlinePlus: Bone Marrow Aspiration

MedlinePlus: Bone Marrow Biopsy