What to expect: bone marrow biopsy

This is a procedure that you may need before a diagnosis or as an ongoing part of your treatment

Eight minute read

What is bone marrow? 

Bone marrow is the spongy, fatty tissue inside the large bones of the body that makes blood cells. It contains liquid and solid components. The following blood cells are formed in the bone marrow:

  •       Red blood cells that carry oxygen to the body’s tissues and organs 
  •       White blood cells that help the body fight infection and disease
  •       Platelets that help the blood clot and control bleeding

If you have clinical symptoms that might suggest a blood cancer, your haematologist will perform a bone marrow test to check if your bone marrow cells are normal, or if there is a blood cancer affecting your bone marrow 

What is a bone marrow test?

A bone marrow test can be either a bone marrow aspiration or a bone marrow biopsy. 

  •       A bone marrow aspiration removes a sample of the liquid portion of the bone marrow which contains some of the bone marrow cells.
  •       A bone marrow biopsy removes a small, solid piece of the bone marrow. 

These samples of bone marrow are taken for the purpose of diagnosing different types of blood cancer. 

Both tests will show abnormal changes in the bone marrow cells, but a biopsy can also give added detail of the structure of the bone marrow such as fibrosis in the bone marrow. Your haematologist will determine whether you need one or both of these tests.

In addition to being able to diagnose a blood cancer, a bone marrow biopsy can also provide the following information:

  •       Extent of your response to treatment for the blood cancer ·      
  • Presence of abnormal chromosomes, often related to the blood cancer, which helps determine your risk from the blood cancer and decide a treatment plan
  •       Progression of the blood cancer 
  •       Causes of severe anaemia (low red blood cell count) or a low platelet count 

Abnormal changes to blood cells affected by the blood cancer can eventually be seen in a blood sample, however these changes can be seen earlier in a bone marrow sample. Moreover, not all patients will have these abnormal cells in the blood. 

Bone marrow aspiration and biopsy procedures

Please note: The following information is for adults undergoing a bone marrow biopsy. For more information on children having bone marrow biopsies, please see this page from CCLG https://www.cclg.org.uk/Bone-marrow-test

Bone marrow aspirations and biopsies are usually taken from your hip bone, in your lower back at the level of the hip. It may also be taken from your sternum (breastbone). These are flat bones, most suited for these two types of bone marrow tests. 

To help us write this information, we conducted an anonymous survey of blood cancer patients where we asked questions about various aspects of their own experience of these procedures. The results from this survey have influenced the text below. 

Prior to the procedures

You should receive a detailed explanation of the procedure and how to prepare for it. In our survey of 178 patients, it revealed that 49% of people were given details of the procedure before it took place. 35% said they didn’t receive information and 16% said they couldn’t remember. 

If you do not receive information, ask your clinician (doctor) for this. 

Our survey also revealed that as many as 1 in 10 people did not understand or fully understand why they needed this procedure. If you do not understand anything about what is about to be done, ask all the questions you need to so you feel fully informed about why this is happening. 

Before the procedure

You can eat or drink normally prior to the procedure as you are not having a general anaesthetic. If you are having a sedative, this may not be the case (please see our section on sedation) 

Your haematologist will check all the medications and supplements you are taking. You may not be able to take certain medications before the procedure, such as blood thinners, which may increase the risk of bleeding. If you are unsure about anything, ask your Doctor to check. 

You will also be asked to sign a consent form for the procedure. This form states that you agree to the procedure and you understand its benefits and risks. If you don’t understand the benefits and risks, ask for further clarification and don’t be afraid to ask as many questions as you need to. 

Bone marrow aspiration and biopsy procedure

These tests are usually performed in the outpatient department of the hospital. According to our survey, this test could be performed by different roles ranging from a Consultant to a Nurse who you may or may not know. You may want to ask who is doing your biopsy. 

You will be asked to lie on a couch on your side with your knees tucked up into your chest. You will be able to keep your underwear on. 

In the procedure itself, the following will happen: 

  •       Special hollow biopsy needles are used to remove:

o   A small amount of liquid containing some bone marrow cells, in the case of an aspiration

o   A tiny core of bone marrow tissue, using a larger trephine needle which can remove a 1-2 cm core of bone marrow in one piece, in the case of a biopsy.

The whole procedure will take approximately 30 minutes. 

Pain relief 

Before the needle is inserted, you will have a local anesthetic to the area. This may cause a little pain before the skin starts to numb. 

Some people take ibuprofen or paracetamol before the procedure

Some people are offered gas and air. It may be referred to as Entonox. Gas and air is a pain-relieving gas mixture made up of 50% nitrous oxide and 50% oxygen. It can be used to control pain during some procedures. It won’t send you to sleep, however, it may help you to relax. 


Some patients have had bone marrow biopsies with sedation. A sedative can make you feel more calm about a procedure, but it won’t send you to sleep. 

If you have sedatives, you will need somebody to take you home after the biopsy in a car or taxi. You won’t be able to drive or take public transport as you may be drowsy or feeling unwell. You will also need somebody to stay with you for around 24 hours after sedation. If this is not possible, you need to inform your healthcare team. 

Before having a sedative, you may need to go nil-by-mouth – this means no food or drink before a procedure for a certain amount of time. Your healthcare team will be able to tell you what you need to do before having sedatives. 

Sedatives may not be available for all people, particularly if you have other conditions such as severe respiratory disorders or if you are pregnant. 

Although the procedure only takes 30 minutes (approx), if you have a sedative, you may need to stay in hospital for a few hours to check you are fully awake and well enough to go home. 

After the procedures

A small dressing will be placed over the site and this should be kept on for 24 hours, during which time you should not bathe or go swimming. 

You are able to go home the same day about an hour after the test. If you have had sedation, which will make you drowsy, you will need someone to drive you home. 

Side effects 

Side effects following bone marrow tests vary from person to person. 

Some patients experience slight bone pain for a few days after the procedure which responds to normal painkillers such as paracetamol.

Other side effects may include bruising, bleeding, pain, infection or tingling in the legs.

  • In the event of any bleeding, pressure should be applied to the area. If it does not stop, contact the hospital.
  • Infection will be apparent if you have a temperature or if the area becomes red and sore. You should contact the hospital in case you need antibiotics.
  • Tingling in the legs wears off with time.

Receiving your results

Bone marrow samples are sent to the laboratory for testing. Both samples will be examined under a microscope and analysed.

  •       A bone marrow aspiration sample is spread onto a microscope slide to and examined to detect any changes in the bone marrow cells and possible chromosome changes 
  •       A bone marrow biopsy sample is sliced very thinly so that it can be viewed under the microscope to see how the bone marrow cell lie in the bone marrow 
  •       The results are generally available after two weeks. 

Awaiting your test results can make you anxious. Contact your haematology clinical specialist nurse who can talk it through with you if you are worried. If you don’t think you have anybody to speak to at the hospital, why not ring our help line? Our nurse is happy to chat through any questions you may have. The help line is open Monday – Friday 9am – 5pm and Thursday and Friday evenings 7pm – 10pm. The number is FREEPHONE 08088 010 444. Alternatively, you can email her on nurse@leukaemiacare.org.uk.


Blog post published on: 30th April 2021

Blog post last updated on: 30th April 2021

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