Skip to main content
Beginner 5 min read

What to Expect During a Bone Marrow Biopsy

A calm overview of what a bone marrow biopsy involves — how the sample is taken, why sedation or anesthesia may be used

NCI source:NCI last reviewed 2023-01-17

Review status: AI-assisted, source checked. Not reviewed by a clinician. How we check pages

The short answer

A bone marrow biopsy removes a small sample of tissue or fluid using a needle, so a pathologist can examine it under a microscope. Some biopsies use a sedative or local anesthesia to help you stay comfortable. Bone marrow samples are often studied further, including cytogenetic analysis and immunophenotyping, especially to help diagnose blood cancers like leukemias or lymphomas.

  • A biopsy removes a sample of tissue or fluid that a pathologist examines under a microscope.

  • Bone marrow aspirations use a needle to withdraw the sample, similar to how some other biopsies are done.

  • Some biopsies use a sedative, which helps you relax and stay still or sleep, or local anesthesia, which numbs a small area.

  • Bone marrow samples can be examined for cells, and are often studied further with cytogenetic analysis and immunophenotyping.

Choose how you want to read this

The whole article, with every detail and caution.

The short version

If your doctor has recommended a bone marrow biopsy, it helps to know the basic idea before the appointment. A biopsy removes cells or tissue so a pathologist can examine them. For a bone marrow biopsy, the sample comes from inside a bone and is taken with a needle.

Why bone marrow is examined

Bone marrow can be examined cell by cell, which gives your care team information other tests cannot. That matters most for diagnosing blood cancers, such as leukemias and lymphomas, because those cancers start in the cells the marrow makes.

Marrow samples are often studied further with tests called cytogenetic analysis and immunophenotyping. These look closely at the cells, including their chromosomes and the markers on their surface. The results help your doctor see exactly what is happening and reach a diagnosis.

How the sample is taken

MedlinePlus says the sample is usually taken from the pelvic bone. Your provider cleans the skin and numbs the skin and the surface of the bone. A biopsy needle is then put into the bone to collect a tiny core of marrow. Pressure and then a bandage are put on the skin afterward. NCI says a needle is also used for bone marrow aspiration, which draws out fluid.

Managing comfort during the procedure

Some biopsies use a sedative, a medicine that helps you relax, stay still, or sleep during the procedure. Others use local anesthesia, which takes away feeling in one small area of the body. Which one is used, or whether both are, depends on your procedure and your care team's approach. Ask ahead of time, so you know what comfort measures will be in place.

What happens to your sample

Your sample goes to a pathologist, a doctor who examines tissue and fluid samples under a microscope. The pathologist studies it, sometimes alongside cytogenetic analysis and immunophenotyping. They then describe what they find in a document called a pathology report. Your doctor uses that report to explain your results and your next steps.

While you wait for results

Waiting for a pathology report can be one of the harder parts of this, emotionally. It helps to ask your care team roughly how long results usually take, and who will go over them with you. Then you have a sense of the timeline instead of an open-ended wait.

Questions for your team

Before your biopsy, ask what comfort measures will be used. Ask which tests will be run on your sample. Ask roughly when results should come back. Clear answers ahead of time can make the day of the procedure feel much more manageable.

When to get help sooner

  • Call 911 or go to an emergency department if the puncture site bleeds heavily or keeps bleeding despite firm pressure. Also go if it soaks through the dressing, or swells fast into a firm lump. Do not drive yourself.
  • Call 911 or go to the nearest emergency department if you have black or tarry stool. Also go if you vomit blood or material that looks like coffee grounds, you suddenly cannot urinate at all, or you are suddenly confused or hard to wake. Do not drive yourself.
  • Call your care team right away, day or night, if you are having chemotherapy and your temperature reaches 100.4°F (38°C) or higher. Call right away too for chills, a sore throat, mouth sores, burning when you urinate, or redness at the site, even with a normal temperature. CDC lists fever during chemotherapy as an emergency that needs a call right away. If you cannot reach them quickly, go to an emergency department and say you are on chemotherapy.
  • Call your care team the same day if you run a fever and are not currently having chemotherapy (see above if you are). Also call if the skin around the site turns hot, red or begins to ooze.
  • Call your care team within a day or two if soreness at the site keeps building over the days afterward instead of easing off. Also call if a sedative leaves you feeling groggy or unsteady well beyond the day of the test.

Sources for this section: MedlinePlus — Bone Marrow Biopsy, CDC — Fever and Cancer Treatment and NCI — Infection and Neutropenia During Cancer Treatment.

A composite image: illustration of a biopsy needle, a blood sample vial, and a microscope tissue slide

Common questions

What is a bone marrow biopsy?

A bone marrow biopsy is a type of biopsy that removes a sample of tissue or fluid from the bone marrow using a needle, so a pathologist can examine it under a microscope.

Does a bone marrow biopsy hurt?

Some biopsies require a sedative, which helps you relax and stay still or sleep, or local anesthesia, which causes loss of feeling in one small area. Ask your care team what will be used for your procedure so you know what to expect.

Why do I need a bone marrow biopsy?

Bone marrow can be examined for cells, and cytogenetic analysis and immunophenotyping are often done on bone marrow samples to help diagnose blood cancers such as leukemias and lymphomas.

What happens to the sample after it's taken?

A pathologist examines the tissue or fluid sample under a microscope and describes the findings in a pathology report.

Are other biopsies done with a needle too?

Yes. A needle is used to withdraw tissue or fluid for bone marrow aspirations, spinal taps, and some breast, prostate, and liver biopsies.

Questions to ask your doctor

Being prepared helps you get the most out of your appointments. Save or print these questions.

Open my question list

Tap a question to save it to your list (kept on this device).

Your next step

Get ready with a checklist and questions for the visit.

Open the appointment prep tool
Talk to a person

Talk with a trained specialist or navigator

Cancer Explained provides educational guidance, but does not replace trained specialists, social workers, or your medical team.

Free & Confidential

Talk to a trained cancer information specialist

Free, confidential assistance from NCI Cancer Information Service via phone, chat, or email.

Contact your oncology team

Locate after-hours contact numbers, portal messages, or urgent triage phone lines.

Find a patient navigator

Get one-on-one help with appointments, logistics, translation, and care coordination.

Find a genetic counselor

Discuss inherited mutation risk, family history, and genetic testing options.

Find an oncology social worker

Access emotional counseling, family support groups, and mental health resources.

Find a financial navigator

Locate copay assistance foundations, grant programs, and lodging/travel support.

Find a clinical-trial specialist

Search matching studies and speak with NCI trial information specialists.

Get urgent help

Fever of 100.4°F (38°C) or higher during chemo, severe pain, or trouble breathing: call your cancer care team right away, day or night. Call 911 for an emergency.

Know someone who needs this?

Plenty of people are looking for something like this and do not know where to start. If this would help a friend or someone you love, send it on — we have written an opening line so you do not have to stare at an empty message. You can change every word of it.

Email itText itWhatsApp

Your message is written and sent in your own email or messaging app — we never see who you send it to, and nothing is added to any list.

Prepared by Cancer Explained's AI-assisted editorial system

Written from National Cancer Institute material and compared with the source cited below.

Plain-language explanation of the published sources cited on this page. AI-assisted, source-checked, not clinician-reviewed.

Last updated: 2026-09-29Next planned review: 2027-07-14

Review details and limits

Cancer Explained does not originate medical claims. Every page restates guidance already published by the National Cancer Institute, the CDC, the USPSTF and the FDA, in plain language, with the source cited so you can check the original yourself. AI does the translating and organizing; automated checks test claims, citations, clarity and safety before anything publishes, and this is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.

Editorial status — Source checked. This page was written with AI assistance and then compared with the sources listed on it, looking for statements those sources do not back up. That check is not a sentence-by-sentence record and can miss errors. It is not a medical review, and it does not confirm the page is complete or right for your situation.

General education — varies by person. Answers genuinely differ between people. This page explains what commonly varies and points you to your care team for your situation.

Human medical review: not completed. Pages here are not signed off by a clinician before they publish. That is not an oversight we are quietly working around: we restate published guidance and cite it, so the authority belongs to the source rather than to us, and every page names where its claims come from — you can verify us instead of trusting us. Where a volunteer clinician has reviewed a page, their name and credentials appear on it; where no name appears, no clinician has checked it. We are glad to have reviewers and are recruiting them, and we do not hold pages back waiting for one. Use this site to understand your situation and to ask better questions of the people treating you.

Our editorial processHow we use AIReport an error

More on this topic

Words to know

Tap any term to see what it means.

Browse the full glossary →

Knowledge check

0 of 4 answered

  1. Q1.According to this article, what is a biopsy?
  2. Q2.How is a bone marrow aspiration sample collected, according to this article?
  3. Q3.What might be used to help you stay comfortable during a bone marrow biopsy, according to this article?
  4. Q4.Why is bone marrow often studied with cytogenetic analysis and immunophenotyping, according to this article?

This self-assessment checks understanding of educational content only. It is not medical advice.

How this page was created

Cancer Explained does not originate medical claims. Every page restates guidance already published by the National Cancer Institute, the CDC, the USPSTF and the FDA, in plain language, with the source cited so you can check the original yourself. AI does the translating and organizing; automated checks test claims, citations, clarity and safety before anything publishes, and this is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.

Editorial status: Source checked — This page was written with AI assistance and then compared with the sources listed on it, looking for statements those sources do not back up. That check is not a sentence-by-sentence record and can miss errors. It is not a medical review, and it does not confirm the page is complete or right for your situation.

Human medical review: not completed. Pages here are not signed off by a clinician before they publish. That is not an oversight we are quietly working around: we restate published guidance and cite it, so the authority belongs to the source rather than to us, and every page names where its claims come from — you can verify us instead of trusting us. Where a volunteer clinician has reviewed a page, their name and credentials appear on it; where no name appears, no clinician has checked it. We are glad to have reviewers and are recruiting them, and we do not hold pages back waiting for one. Use this site to understand your situation and to ask better questions of the people treating you.

Read more about our editorial process, our use of AI, and our corrections policy.

Spotted a problem? Report an error — a factual mistake, broken or outdated source, confusing wording, or anything that seems unsafe. Please do not include names, medical record numbers, dates of birth, addresses, or other identifying medical information in your report.

After using this page, do you understand what to do next?

Anonymous — we only record the answer, never who gave it.