Six Myths about Donating Bone Marrow and Stem Cells

Medical oncologist Parastoo Dahi (left) specializes in treating patients with stem cell transplants.

Medical oncologist Parastoo Dahi (left) specializes in treating patients with stem cell transplants.

What would you do if you found out that your bone marrow was a match for someone who needed it — even a complete stranger?

Bone marrow and stem cell transplants are a lifesaving treatment for many people with blood cancers like leukemia and lymphoma, as well as some other blood diseases.

During a transplant, patients are given high doses of chemotherapy and sometimes radiation to wipe out their cancer. These powerful treatments also destroy the blood-making cells, however. So the next step is for healthy blood stem cells to be infused into the body, enabling the patients to grow new blood cells and recover from the treatment.

Although some patients can use their own stem cells to rebuild the blood, many patients — especially those with leukemia whose blood stem cells may themselves be cancerous — need a donor to provide the cells that will enable them to recover.

One way that donors are found is through the National Marrow Donor Program, a group that maintains a registry to match unrelated volunteer donors with patients in need. Many people are reluctant to join this registry because they don’t understand what’s involved or how important their donation may be. We spoke to Parastoo Dahi, a hematologist and medical oncologist at Memorial Sloan Kettering who specializes in stem cell transplantation, about some of the myths surrounding bone marrow and stem cell donation.

Myth 1: Stem cell donations always come from the bone marrow.

“We still commonly use the term ‘bone marrow transplant,’ but more often than not, what we really mean is a transplant using stem cells that are removed from the bloodstream rather than the marrow,” Dr. Dahi says.

The doctor performing the transplant will decide which procedure will be used to extract the stem cells based on what he or she thinks will be best for the recipient. But the majority of donations are taken from the blood, not the bone marrow.

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Myth 2: Making a stem cell donation is difficult and painful.

With stem cell donation from the blood, there is very little pain involved. It is very similar to donating blood platelets. The main difference is that for a few days before the donation, donors need to take an injection called filgrastim (Neupogen®), which stimulates the bone marrow to produce extra blood-forming stem cells. They may experience some bone pain or a low-grade fever while taking filgrastim, but the side effects usually are not severe and go away after the donation process is complete.

Bone marrow donation, the less common form of donation, is a surgical procedure done in an operating room. Donors are given general anesthesia so they don’t feel any pain as the bone marrow is removed, or aspirated, from both sides of their pelvis.

“The procedure takes an hour or two, and usually donors can go home within a few hours of waking up,” Dr. Dahi says. “They may have some pelvic and hip pain, as well as some bruising, for a few days, but most donors can immediately go back to their regular activities. The achiness can generally be controlled with over-the-counter pain medications.”

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Myth 3: Stem cell donation is inconvenient.

Leading up to the time of the stem cell donation, most people are able to give themselves injections of filgrastim at home, so they don’t need to go to the doctor every day.

On the day of the donation, the donor is hooked up to what is called an apheresis machine. The blood is collected from one arm, sent through a machine that removes the stem cells, and returned to the other arm. Donors can read or watch movies during the donation process.

Dr. Dahi says the process takes three to four hours, and the donor may need to return a second day, depending on how many cells are retrieved.

In the cases of both bone marrow and blood stem cell donation, the donor cells can be retrieved at a local hospital or blood donor room and shipped to where they are needed. The donor and recipient may live in different states, or even in different countries.

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Myth 4: Most patients can find a stem cell donor in their own family, so there’s no reason to join the registry.

The process by which the donor and recipient are matched is called HLA (human leukocyte antigen) typing. It’s not related to blood type but instead has to do with the immune proteins that we all inherit at birth from both of our parents. “The immune system uses these proteins to understand which cells belong to your body and which do not,” Dr. Dahi explains. “An optimal match means that eight out of eight markers are the same.”

According to Dr. Dahi, about one-quarter of patients have a sibling who is a perfect match. This means that about 75% of cancer patients must rely on potential donors from the registry.

Even if a sibling is perfectly matched, there may be medical reasons why they are unable to donate. Medical restrictions include infections such as HIV and hepatitis, autoimmune diseases such as lupus, bleeding problems, and a history of cancer. “It’s important to make sure that the process is safe for both the donor and the patient,” she says.

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Myth 5: There are plenty of people already in the stem cell donor registry, so my contribution isn’t needed.

Not everyone who needs a donor is able to find one. “For members of minority groups, there can be major problems finding donors because they tend to be underrepresented in the registry,” Dr. Dahi says. “Different ethnic groups have different HLA types, so a patient’s best chance of finding a donor is someone within their own ethnic group.” It may be even harder for people of mixed ethnic backgrounds to find donors, because their HLA makeup can be more complex.

For patients who are unable to find matched donors, there are other options, including a donation from a family member who is a half-match (called a haploidentical transplant) or using stem cells from donated umbilical cord blood, which don’t require a full match. “We don’t want patients to delay their treatment if they don’t have a perfect match,” she adds, “but it’s still the standard to go with a donor who is a perfect match whenever possible.”

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Myth 6: Getting into the stem cell donor registry is a hassle.

Joining the registry is easy. You can go to to order a collection kit that will be sent to your house or to find a local drive in your area. Once you get the kit, all it requires is wiping a cotton swab on the inside of your cheek, sealing it in a provided container, and mailing it back.

Because the most successful donors are between the ages of 18 and 44, the National Marrow Donor Program asks that people between the ages of 45 and 60 make a $100 contribution to cover the costs of testing their swab.

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Commenting is disabled for this blog post.

Is there a link to register for the event?

MSK is partnering with Be The Match to host a stem cell donor registry drive to identify potential new stem cell donors for the National Bone Marrow Donor Registry. To RSVP for one of our events and learn more about dates, locations, and eligibility, please visit Thank you for your interest.

Is it possible for a donor to choose to enroll only in the non-surgical procedure type of donation?

Hi Niam, if you are in the donor registry and your cells are found to be a match for someone in need, the cancer patient’s doctor would ultimately decide the method to retrieve your cells based on what was best for the patient. If it got to that point, you would have the option to decline making the donation. Thank you for your comment.

Hello my husband has Aml and relapsed In june and is back in remission. He has a bone marrow transplant from his sister who was a perfect match. And the Dr's want to use his sisters again. Just wondering if it makes since to use his sister again . Thank you anything to help us out.

Dear Ira, we are sorry to hear about your husband’s diagnosis. It’s difficult to answer specific questions about a treatment recommendation without knowing more about his medical/treatment history. If he is interested in making an appointment with one of our specialists for a second opinion, please ask him to call our Physician Referral Service at 800-525-2225. Thank you for reaching out to us.

Could Dr. Dahi please comment on risk of serious adverse effects for bone marrow donors? In particular, the possibility of any long-term health effects from the filgrastim injections, and any concerns about clotting or anestheia among women who are in their 40s, and for infection? Would so appreciate hearing more. I have small children and my first obligation is to them but I would really like to help someone else.

Hi, we sent your questions to Dr. Dahi, and this is her response:

The most common risks associated with donating bone marrow involves the use and effects of anesthesia during surgery and pain in the area where the bone marrow was taken out.

The most common risks associated with filgrastim and peripheral blood donation involve bone pain, muscle aches, headache, fatigue, nausea, and vomiting.

The risk for donors of allogeneic hematopoietic stem cells transplants is generally negligible, however, serious adverse events (such as heart attack, stroke, bleeding in the brain, splenic rupture, malignancies, etc.) and fatalities have been reported in a large European registry study. You can learn more about that study here:

Thank you for your comment.

I was excited to register to donate, but then saw I had to give $100 because I am 56. This is a serious deterrent. Am I not a good candidate? I am healthy! Totally illness free. Confused.

Dear Karen, we’re so glad that you want to sign up to be a donor. According to, people between the ages of 18 and 44 are selected as the best donor more than 95% of the time. This is because younger donors offer the best chance for success in the patient. Those between the ages of 45 and 60 are still able to donate, and may be needed if a younger person with a match is not found. We recommend you contact the National Marrow Donor Program if you have more questions. They can be reached at (800) MARROW-2. Thank you for your comment.

I am a perfect match for my 67 year old sibling. I am 70 years old & went for evaluation however, I am petrified after reading reports that I run the risk of developing AML after Filgrastim exposure. Advice, please?

Dear Bev, we sent your question to Dr. Dahi, and she replied that a 2009 study (Joerg Halter et al Haematologica 2009;94,) found incidence rates of blood cancer for both bone marrow and stem cell donors to be below the age-specific incidence rates for a normal population, suggesting that there was no increased risk. But she also noted that family predisposition for blood cancer may play a role in developing hematologic malignancies. If you have any concerns about this, we recommend that you discuss them with your sibling’s healthcare team or with your own doctor. Thank you for your comment, and best wishes to you.

Is their an age cutoff for donors? I thought I heard once that they don't want blood marrow donors over 40.

Dear Laika, preferred donors are between the ages of 18 and 44, but people up to age 60 can donate if a younger matched donor is not available. You can learn more at Thank you for your comment.

I was a bone marrow donor for my father 23 years ago to cure his leukemia successfully. I remain on the Nation Registry and would donate at any time at the drop of a hat. The pain I experienced after the surgical procedure was noting more than a bruised feeling in the tea where the needles were inserted. I took Tylenol for two days and then nothing. To know that you can save someone's life with very little to no impact to your life should be reason enough for you to register. If that is not enough, imagine if you had a family member in need of a donation and their type was not on the registry........imagine what that must feel like! That is why we need to build our registry to insure that families who do not match the recipient have the same chance at life as anyone else! My father celebrate 23 years leukemia this past August thanks to this amazing procedure!

My husband and I wee surprised to find out that we "aged" out of Bone marrow donation registry. We noticed we were not receiving usual updates and then I asked what happened. Since we are healthy and willing, is it sure we can't still be able to help someone? We do financial donations regularly.

Dear Barbara Ann, the preferred age for donors is between 18 and 44, but people as old as 60 can donate if younger donors are not available. Blood stem cells from younger donors are more likely be successful, which is why they are preferred. If you would like to learn more, we recommend that you contact Thank you for your comment and for your support of the bone marrow registry.

I went through chemotherapy for a localized cancer. It's been more than 5 years since treatment and more than 5 years cancer free. Would I be a candidate to donate?

Dear Mandy, the guidelines state that you can join the registry if you had any type of cancer other than blood cancer and if it meets ALL of the following criteria:

More than 5 years since diagnosis
No recurrence or metastases
No chemotherapy or radiation*

If you would like more information on this, we recommend that you go to

We’re glad to hear that you’re cancer free. Thanks for your comment and best wishes to you.

Hi my daughter gave her brother bone marrow both my adult kids
Soninlaw said now she has none of my genes is this true

Dear Margaret, a bone marrow transplant does not change the genes that someone is born with and inherits from their parents. Thank you for your comment and best wishes to you and your family.

I am 50 years old and I registered when I was younger. They contacted me a couple of months ago for Stem Cell donation since I was a perfect match with a five year old patient. we found out my mom has stomach cancer about two months ago. Given the fact that I may have the potential for the disease as well, doesn't going through the shouts and collection of stem cells make my body vulnerable or does not effect my own bones since I am going through menopause and I still have a 13 years old a 15 years old to take care of and no help.
I was reading above about the risks such as heart attack, stroke, bleeding in the brain, splenic rupture, malignancies, etc.. and they make me worried. I have to start the shouts in two days and I feel they are counting on me and I can not change my mind anymore either.

Dear Nooshin, the risks from donating stem cells are very low. We recommend that you discuss this with your healthcare team and the doctors that you are working with on the transplant. Thank you for your comment, and best wishes to you.

My brother no longer wants to be a donor so I'm unexpectedly next match for my sister which is fantastic but I was told I need to stop breastfeeding. If the drug simply increases stem cells why would it be harmful?

Dear Priya, we’re happy to hear that you’re a match for your sister. We recommend that you discuss this with your sister’s care team. Thank you for your comment, and best wishes to both of you.

Hi! I have been recently matched to someone. Going through the pre screening they told me my veins were not very big or even visible to do it through my arms and they would have to go through my groin. How different is than than the arms? Are there different side effects or risks that I should be aware of other than what they’ve already explained when I was doing it through my arms? Thanks!

Dear Sandra, that’s great news that you’ll be able to donate to a patient in need. We recommend you discuss any of your questions or concerns with the doctors and nurses who will be performing the procedure. Thank you for your comment, and best wishes to you.

My husband is a perfect match to be donor for his sister ... he had prostate cancer surgery 12 yrs ago and his PSA levels have been below zero since last year. over the past few blood tests there has been a slight increase in PSA levels, he is also 67 yrs. old. Would he still be a potential donor??

This is something that your husband and his sister should discuss with her doctor. A history of cancer doesn’t automatically disqualify someone from donating, depending on how long it’s been and what kind of treatment they had. But transplants from younger donors (under age 44) tend to be more successful because the cells are of higher quality. Thank you for your comment, and best wishes to you.

I am in remission from ALL. I was diagnosed in Sept 2014. In remission since Oct 2014. Finished treatment in Jan 2018. I am 53. Am I eligible to donate stem cells?

Dear Ira, we’re glad to hear that you’re doing well. Unfortunately, people who have had chemotherapy are not able to donate stem cells. In addition, the ideal donors are between the ages of 18 and 44. Thank you for your comment and best wishes to you.