Hematologist
CION Cancer Clinics
Bone marrow test: what it involves and how much it hurts | CION Cancer Clinics
A bone marrow test usually hurts for a few seconds. After the skin and bone surface are numbed, you feel pressure and a short, sharp pull as liquid marrow is drawn from the back of your hip bone. It is not taken from the spine. Most people go home the same day with a sore back. Here is each step, what the laboratory looks for, and when to seek help. At CION Cancer Clinics, our haematologist reviews abnormal blood reports with you, orders only the tests that answer your question and explains each result plainly.
BP
Medically reviewed by Dr. Basudev PokhrelConsultant Haematologist · last reviewed September 2026, next review due September 2027
17+specialists on panel
15,000+patients treated
35+centres across Telangana & AP
4.8★ / 800+Google rating
On this page
- Does a bone marrow test hurt?
- What happens from arrival to going home?
- Why has your doctor asked for a bone marrow test?
- What do they look for in the sample?
- What do families fear about this test that is not true?
- How long do results take, and what can they not tell you?
- Common questions about the bone marrow test
The short answer
Does a bone marrow test hurt?
Most people feel a sting from the numbing injection, then pressure, and a short, sharp pulling pain when the liquid marrow is drawn out. The whole test is usually over in well under an hour, and most people go home the same day with a sore back for a few days.
Where the sample comes from
The sample is almost always taken from the back of the hip bone, just below your waist on one side. It is not taken from the spine, and it does not touch the spinal cord or the nerves to your legs. In a few situations the breastbone is used instead, but only for the liquid part.
Why the pain is brief
The skin and the outer layer of the bone are numbed first. The inside of the bone cannot be fully numbed, which is why the moment of drawing out the liquid feels like a deep ache or tug. That moment lasts only seconds. Tell the doctor as it happens, and they can pause.
If you are very anxious
Ask before the day whether a mild sedative or pain relief is possible. Some centres offer it, and it can make a real difference for people who fear needles. You will then need someone to take you home.
Everyone feels it differently. A person who had a hard time once often finds a second test easier with more numbing and a slower pace.On the day
What happens from arrival to going home?
Checks before you start
The team checks your recent blood counts, asks about allergies and blood thinners, and explains the test. You sign a consent form. Ask any question you have at this point, before you lie down.
Positioning and numbing
You lie on your side with your knees drawn up, or on your front. The skin over the hip bone is cleaned, and a local anaesthetic is injected into the skin and onto the bone surface.
The aspirate
A hollow needle passes into the bone and a syringe draws out a small amount of liquid marrow. This is the brief pulling pain most people remember.
The trephine
A slightly wider needle takes a thin core of bone, like a short piece of pencil lead. You feel pushing and some twisting, then it is done. Pressure and a dressing go on the site.
Rest and home
You lie on your back for a short while to press on the site. Most people walk out the same day and can eat normally.
Not sure whether this applies to you?
Ask an oncologistThe reason for it
Why has your doctor asked for a bone marrow test?
Your bone marrow is the factory inside your bones that makes red cells, white cells and platelets. A blood test shows what leaves the factory. A bone marrow test shows what is happening inside it.
Common reasons
It is usually asked for when blood counts are unexplained: a low haemoglobin, a low platelet count or odd white cells that repeat blood tests have not explained. It is used to confirm or rule out leukaemia, myeloma, lymphoma and myelodysplastic syndromes, and to check whether treatment for these has worked. It also helps with aplastic anaemia, where anaemia means the marrow is making too few cells.
Who should tell the team something first
Tell the team if you take any blood thinner, aspirin or painkillers, if you bleed or bruise easily, if you are pregnant, or if you have ever reacted to a local anaesthetic. Do not stop any medicine on your own. The treating team decides whether anything changes before the test.
Where the test is done
CION's haematology team evaluates your case, discusses it at a tumour board and coordinates the test with a qualified centre where needed. Ask where the sample will be taken, and which laboratory will read it.
In the laboratory
What do they look for in the sample?
One test can send the marrow to several laboratories. That is why results come back in parts.
Looking at the cells
A specialist looks at the liquid marrow under a microscope, counting the types of cells and checking whether any look abnormal. This part is often ready first.
The core of bone
The trephine shows how full the marrow is and whether anything has replaced the normal tissue, such as scarring or lymphoma. It needs softening before it can be cut, so it takes longer.
Flow cytometry
A machine reads the markers on the surface of thousands of cells. It helps name the exact type of leukaemia or lymphoma.
Chromosome and gene tests
These look for changes inside the cells that guide treatment choice and help your haematologist understand the outlook.
You may see on the report
- Cytogenetics or karyotype
- FISH
- Molecular or NGS panel
Leave a number, we will call you
One field. No form to fill in, and no charge for the call.
!
After the test: when to get help the same day
Some soreness and a small bruise are expected. If the dressing keeps soaking through with blood despite firm pressure, if the pain keeps getting worse instead of better, if the site becomes hot, red or swollen, or if you develop a fever or shivering, go to the nearest emergency department today or call 108. Tell them you have just had a bone marrow test. This matters even more if your counts are low.
Commonly believed
What do families fear about this test that is not true?
"They take it from the spine, so it can cause paralysis."
The sample comes from the hip bone, not the spine. The needle does not go near the spinal cord. This test is often confused with a lumbar puncture, which is a different procedure.
"Taking marrow out will make the body weak."
The amount taken is very small compared with all the marrow in your body, and it is replaced naturally. You may feel tired from the worry and the day, but the test does not drain your strength.
"If they want a bone marrow test, it must be cancer."
Many tests are done to rule cancer out, or to explain conditions that are not cancer, such as some types of anaemia or low platelets. The request tells you your doctor needs more detail, not what the answer is.
"Poking the marrow will spread a blood cancer."
Blood cancers already travel through the blood and marrow. The needle does not spread them. Delaying the test only delays the diagnosis and the start of the right treatment.
Being straight with you
How long do results take, and what can they not tell you?
The first look at the cells may come back within a few days. The bone core, flow cytometry and gene tests often take longer, sometimes a couple of weeks, and the full picture is only clear when all of them are in.
Why a partial report can mislead
An early report may say something is suspicious without naming it. Try not to act on part of the result. Your haematologist waits for the pieces that decide the type and the treatment, and will explain them together.
What this page cannot tell you
This page cannot tell you why you need the test, what your result will show, or what your outlook is. It also cannot predict how much it will hurt for you. Ask your doctor what they are looking for, which results will change the plan, and when you should expect each one.
Questions we are asked
Common questions about the bone marrow test
Will I be asleep for the bone marrow test?
Usually not. Adults are normally awake with local anaesthetic, and some centres add a mild sedative on request. Children are often given a short general anaesthetic so they sleep through it. Ask in advance, because sedation changes whether you can eat beforehand and who must take you home.
Do I need to fast before the test?
With local anaesthetic alone, most people can eat and drink normally. If you are having sedation or a general anaesthetic, you will be told when to stop eating. Follow the instructions from the centre doing the test, as they vary. Take your usual medicines unless your treating team says otherwise.
How long will my back be sore?
Most people have an ache and some bruising at the site for a few days. Ordinary pain relief your doctor has approved is usually enough. Avoid heavy lifting and hard exercise for a short while. If the pain grows instead of settling, contact the team the same day.
Can I drive or go back to work afterwards?
If you had only local anaesthetic, many people can return to light work the next day. Do not drive if you had any sedation, and it is sensible to have someone travel with you anyway. A desk job is easier to return to than physical work, which may need a few more days.
When can I bathe or get the site wet?
Keep the dressing dry and in place for the time the team tells you, usually until the next day. After that, a normal bath is fine. Avoid soaking in a tub or swimming until the small wound has closed. Watch for redness, heat or discharge, which can mean infection.
My platelets are low. Is the test still safe?
Often yes. Bleeding from the hip bone is uncommon even with low platelets, because the site is easy to press on. The team checks your counts and clotting first and may give platelets beforehand in some cases. Never stop or change a blood thinner yourself before the test.
Why do some people need the test again?
A repeat test checks whether treatment has worked, looks for a return of disease, or is needed when the first sample was too small to read. It does not mean something went wrong. Ask your doctor what the repeat is meant to answer.
What should I ask before agreeing to the test?
Ask what the doctor expects to learn, where the test will be done, whether sedation is available, and which laboratory tests will be run on the sample. Also ask how long each result takes and who will explain them. Bring a family member so two people hear the answers.
Your Haematologist
Meet CION's haematologist. One specialist for your blood report and your plan.
Dr. Basudev Pokhrel reviews blood counts, transfusion needs and blood disorders, and works with the CION tumour board on blood cancers.
Want a specific doctor for your case? Mention them when booking.
Book Free ConsultationBook an appointment with our specialist
Share your name and number — we'll call you back within 30 minutes to schedule your consultation.
Sources
- Cancer Research UK — Bone marrow test
- Macmillan Cancer Support — Bone marrow biopsy
- National Heart, Lung, and Blood Institute — Bone Marrow Tests
- Blood Cancer UK — Understanding blood cancer
This page is general information, not a prescription. Do not change or stop any treatment based on what you read here. If anything is worrying you, contact your own treating team — or call our helpline and we will help you reach the right specialist.
Keep reading
Related pages
Talk to us
Been asked to have a bone marrow test?
Tell us what has been found so far. Our haematology team will go through your reports with you and help you reach the right specialist.