What to Expect During a Bone Marrow Aspirate and Biopsy

Bone marrow is the spongy tissue inside most bones such as those in your hip and thigh. Red marrow contains mature cells, which do not reproduce, and immature cells, which can reproduce. Parent cells, which are also immature, are called stem cells. Ultimately, stem cells will become:

  • Red blood cells that bring oxygen to all your cells
  • White blood cells that fight infection
  • Platelets that help with blood clotting

A bone marrow aspirate is the removal of a sample of the marrow inside the bone. A bone marrow biopsy is the removal of a small piece of hard bone along with marrow.

The Purpose of a Bone Marrow Aspirate and Biopsy

This test is done when the results of a complete blood count (CBC) show abnormal types or numbers of platelets, red blood cells, or white blood cells or to evaluate whether other diseases are present in the marrow. The test may find the cause of the abnormality: some types of anemia (not enough red blood cells), certain types of blood and lymph cancers, or platelet abnormalities. Additional aspirates and biopsies will be used to monitor your response to treatment.

Preparing for Your Bone Marrow Aspirate

  • Do not stop any medications that affect your blood’s ability to clot (anticoagulants) unless you discuss it with your doctor first.
  • If you are on an aspirin regimen, your doctor should tell you to stop taking it 7 days prior to the procedure.
  • You may need to take a short-acting anticoagulant drug such as Lovenox®, which can be stopped 24 hours before your procedure.
  • Tell your doctor if you:
    • take any prescription or over-the-counter medications, vitamins, or herbal or diet supplements – particularly any that affect your blood’s ability to clot
    • have allergies to any medications
    • have bleeding problems
    • are pregnant

Stop taking all nonsteroidal anti-inflammatory drugs (NSAIDs) 3 days prior to the procedure. This group includes over-the-counter and prescription medications such as:

  • Ibuprofen (Advil®, Motrin®)
  • Naproxen (Aleve®, Anaprox®)
  • Piroxicam (Feldene®)
  • Sulindac (Clinoril ®)
  • Fetoprofen

Check with your doctor to see if your instructions will be different.

You must sign a consent form giving permission for the biopsy. You are encouraged to ask questions to understand the procedure; its risks, and benefits.

During the Procedure

The bone marrow aspirate and biopsy (marrow and bone sample) is usually taken from the back of the hip bone. The skin is cleansed, and a local anesthetic is injected to numb the area. An aspirate is usually done first. Once the skin is numb, the aspirate needle is inserted into the bone and a syringe is used to withdraw the liquid marrow. After the aspiration is done, either the needle will be removed and repositioned or another needle will be inserted into the bone for the biopsy. The core of the needle is removed and a tiny sample of the bone and marrow is forced up into the needle. The needle is removed, pressure is applied to stop any bleeding, and a pressure bandage is applied.

How the Procedure Will Feel

There will be a sharp sting from injecting the medication to numb the skin. Since the interior of the bone cannot be anesthetized, this test may cause some discomfort. As the aspirate is withdrawn, there may be a brief, sharp pain. The biopsy may also produce a brief pain, usually more dull. Not everyone will experience these symptoms.

After Your Bone Marrow Aspirate

You will recover in your room, where we will monitor you and check your dressing. You will be discharged shortly after the procedure. Walking may relieve any discomfort you have following the procedure.

Home Instructions

  • The pressure bandage should be removed and replaced 24 hours after the procedure. These supplies will be given to you.
  • Ask your practitioner what you can take to relieve discomfort/pain, if needed.
  • You may take a shower 24 hours after your procedure. While the biopsy site may get wet, do NOT take a tub bath or submerge the site until 48 hours after your procedure.


Persistent bleeding and/or infection are possible; they occur rarely and can be controlled.

Call Roswell Park if you have:

  • Bleeding at the procedure site (apply pressure to the site)
  • Fever of 100.4°F (38°C) or higher
  • Signs of local infection at the biopsy site: redness, swelling, hot to the touch, or drainage
  • Increased pain at the biopsy site
  • A question or concern