Blood stem cell donation ​FAQs

If you signed up online, you’ll receive a confirmation email and a swab kit in the mail to collect your sample. Once you return your kit, your sample is processed to determine your HLA type and is then securely added to the NMDP Registry^SM so doctors can search for matches for their patients.

Behind the scenes your information remains confidential and is only accessed if you’re identified as a potential match.

A swab kit is a simple at-home test used to collect cheek cells so your HLA type can be added to the NMDP Registry.

After you sign up to join the registry, you’ll receive a free kit that is usually delivered within 3-7 business days. If you have questions about how to complete or return your swab kit, check out our At-Home Swab Kit Guide.

If it’s been longer than 7 business days and you still haven’t received your kit or need a new one for any reason, please log in to your My NMDP account to request a new kit.

Doctors look for a donor who matches their patient's tissue type, specifically their human leukocyte antigen (HLA) type. HLAs are genes that code for proteins—or markers—found on most cells in your body. Your immune system uses these markers to recognize which cells belong in your body and which do not. The closer the match between the patient's HLA and yours, the better for the patient.

Because there are so many different HLA types, we can’t predict how likely it is that any one person will be asked to donate. As our population becomes more diverse, it’s harder to find full matches between patients and donors. However, new research and clinical trials from NMDP^SM through our research collaboration CIBMTR® (Center for International Blood and Marrow Transplant Research®) are making it possible for patients to have a successful transplant even when paired with a donor who isn’t a full match. This initiative, called NMDP Donor for All, means more transplants for patients and more opportunities for NMDP Registry members to donate!

Even if you haven’t been contacted after joining, remaining on the registry and keeping your information up to date ensures you’re available if you’re ever identified as a potential match. It’s that continued commitment that could one day make a life-saving difference.

If you match a patient we’ll contact you, confirm you still want to donate and then you’ll undergo more testing to see if you’re the best possible match for the patient. We may ask for another cheek swab or a blood sample, or we may be able to use a stored sample.

If the patient's doctor selects you as the best donor for the patient, we’ll schedule an information session so you can learn more about the donation process, risks and side effects. Though almost all patient information is confidential, we can share the patient's age, gender and disease with you. At that time, we can also confirm the type of donation the patient's doctor has requested—either bone marrow or peripheral blood stem cells (PBSC), collected from your bloodstream.

To protect both donors and patients, medical guidelines are in place to ensure donation is as safe and effective as possible. You must be between the ages of 18 and 35 to join the registry, and once you’re a member, you’ll remain on the registry until age 61 unless you request removal.

Donors should be in overall good health and certain medical conditions like heart disease, autoimmune disorders, HIV or active cancer may prevent donation. Your height and weight is also evaluated to ensure donation is safe for both you and the patient.

If you’re identified as a match, you’ll complete a detailed health history review and physical exam before moving forward. For a complete list of eligibility requirements, please visit our Blood Stem Cell Donation Medical Guidelines page.

Yes, this is completely normal.

Most people who join the registry will never be contacted to donate because patients need a very specific genetic match found through a process called human leukocyte antigen (HLA) matching. With thousands of tissue type combinations, the chance of any one person being the best match at a given time is low, outside of donors directly related to the patient.

It’s also important to remember that even if you haven’t been contacted yet, your decision to donate still matters. Patients rely on a large and diverse registry so doctors can search for the best possible match when it’s needed. Simply staying on the registry provides that hope to patients in need.

Yes. Joining the registry and donating are completely voluntary. You can change your mind at any point in the process. If you do, let us know right away so we can keep searching for another donor. Timing is critical and delays could put the patient’s life at risk.

There are two main ways to donate:

• PBSC donation—most donors (90%) donate via peripheral (circulating) blood. PBSC donation is nonsurgical and done at an outpatient clinic. Before the donation, you’ll get daily shots of a medication called filgrastim for five days to increase blood-forming cells. Then, during the donation, your blood is drawn through a needle, passed through a machine that separates out the blood stem cells and the rest is returned to your body.
• Bone marrow donation—some donors (10%) donate via marrow which is a surgical procedure done in a hospital. While you’re under anesthesia, doctors use needles to collect liquid marrow from the back of your pelvic bone.

When you join the registry, you agree to donate by whichever method is needed for the patient you are matching. Once you’re chosen as a donor, you’ll find out which method will be used either when you’re first contacted or at the donor information session that happens later. The patient's doctor chooses the method that’s best for the patient.

We cover all costs related to donation, including:

• Medical expenses
• The donation itself
• Travel expenses such as hotels, air and ground transportation, and meals for you and a companion
• Childcare
• Pet care
• Lost wages

You will never be asked to pay to donate and donors are not paid for donating.

The full donation process takes time but is flexible around your schedule. Here’s a general timeline:

• Before donation: You’ll attend an info session and have follow-up appointments for blood tests and a physical exam.
• Donation day: Most people donate in one day.
• Total time: Expect to spend 20 to 30 hours over four to six weeks, not counting travel time. Many donors travel and may stay overnight in a hotel.

Your health and safety are our top priority. We partner with experienced medical teams to make sure you receive high-quality care before, during, and after donation.

If a complication arises, we’ll help you get the care you need. As an NMDP donor, you’re also covered by our life, disability and medical insurance for any issues directly related to the donation.

Bone marrow donation is a surgical procedure done in a hospital operating room. The hospital may be near your home or require travel—either way, we’ll handle the logistics and support you every step of the way.

• Arrival and hospital stay: You’ll check in early on the day of your donation. Most donors go home later that day, though some hospitals may plan for an overnight stay.
• Anesthesia: You’ll receive general anesthesia (used in about 96% of cases), which means you’ll be asleep and won’t feel anything during the procedure. Some hospitals use regional anesthesia (like a spinal or epidural), which blocks sensation but keeps you awake. The average time under anesthesia is less than 2 hours.
• The donation itself: During marrow donation, you’ll be lying on your stomach. While the donation varies slightly from hospital to hospital, generally, the doctors use special, hollow needles to withdraw liquid marrow (where blood-forming cells are made) from both sides of the back of the pelvic bone. The incisions are less than ¼-inch long and don’t require stitches.
• Recovery at the hospital: Hospital staff will watch you closely until the anesthesia wears off and continue to monitor your condition afterwards. Most donors go home the same day or the next morning. After you leave the hospital, we’ll contact you on a regular basis to ask about your physical condition and any side effects you may be experiencing.

Bone marrow donation is a surgical procedure, so your body will need time to recover. However, most donors describe the discomfort as manageable and temporary.

Side effects of bone marrow donation may include:

• Soreness in the lower back or hips: After donation, it’s common to feel achy or bruised in the back of your hip area, where the marrow is collected. Many donors compare it to the feeling of soreness after a fall or pulled muscle.
• Stiffness when walking or bending: You may feel tight or tender for a few days, especially when sitting, standing, or climbing stairs.
• Fatigue: Feeling more tired than usual is common as your body replaces the donated marrow.
• Headache: Some donors experience mild headaches after the procedure or as the anesthesia wears off.
• Bruising at the collection site: Mild bruising can occur and typically goes away within a couple of weeks.

We take all the necessary precautions to ensure your safety and well-being. However, no medical procedure is risk-free. Almost all bone marrow donors experience some side effects, but they resolve quickly, and very few donors have long-term or lingering health issues.

Fewer than 1% of donors experience serious issues, such as reactions to anesthesia or damage to bone, muscle or nerves near the donation site.

Recovery time varies from person to person, but most symptoms are temporary and improve steadily over time.

• In the first few days: You may feel soreness in your lower back or hips. It’s also common to feel tired and need extra rest.
• Returning to normal activities: Many people resume work, school and light daily activities within a few days to a week, depending on how physically demanding their routine is.
• Energy levels: Your energy may feel lower than usual for a short time as your body replaces the donated marrow.
• Ongoing support: You’ll be monitored before and after donation, and your medical team will provide guidance to help manage discomfort and support recovery.

No. The body replaces the donated marrow within four to six weeks. Most donors are back to their usual routine within a few days. The amount collected is only a small portion of your total marrow and won’t impact your immune system or overall strength.

The procedure is performed in a hospital that works with NMDP. We’ll arrange the details and coordinate travel, if needed, to make the process as smooth as possible for you.

Peripheral blood stem cell (PBSC) donation is one of three ways to collect blood stem cells for transplantation. The other two ways are bone marrow donation and umbilical cord blood donation. A blood stem cell transplant can help cure or treat more than 75 diseases.

PBSC donation is a nonsurgical outpatient procedure, meaning there’s no surgery or hospital stay involved.

Here’s how it works:

• Before donation: For 5 days, you’ll receive injections of a medication called filgrastim (or an FDA-approved similar). This increases the number of blood-forming cells in your bloodstream. You’ll get the first injection at a donor center or clinic, and the others can be done at your home, workplace or a clinic. You can learn more about filgrastim on our YouTube channel.
• Day of donation: On the fifth day, after your final injection, you’ll donate through a process called apheresis, which is similar to donating plasma or platelets.
• During the procedure: A needle is placed in each arm. Blood is removed from one arm and passed through a machine that separates out the blood stem cells. The rest of your blood is returned to you through the other arm.
• Timing: Most people donate in one session that lasts 4 to 8 hours. Occasionally, a second session is needed the next day, lasting 4 to 6 hours.

All equipment used is sterile and used only once.

On donation day, your NMDP representative will help you feel at ease. They’ll help you in getting as comfortable as possible with pillows, snacks and entertainment. You’ll also have a team of medical professionals ready to provide you with a high standard of care to answer your questions and ensure your donation goes smoothly and safely.

Wear comfortable, loose-fitting clothes, such as sweatpants and a T-shirt. Dressing in layers is a good idea in case the donation room is cool.

You’ll be seated in a reclining chair. To help you stay comfortable, we’ll provide pillows and blankets. Because needles are placed in both arms, your movement will be limited during the procedure.

We encourage you to eat breakfast before you arrive on donation day, unless otherwise informed. If requested, we can provide lunch for you and your companion. Your meals are reimbursable, so be sure to save your receipts. Snacks and refreshments will be provided throughout your donation.

Yes, your companion can stay with you on collection day. NMDP collection centers may change their policies based on current public health guidelines and regulations. Your NMDP representative will inform you of the latest guidelines.

PBSC donation is a nonsurgical procedure similar to donating blood. Most side effects are mild, temporary, and occur during or just after the collection process.

Side effects of the PBSC donation procedure may include:

• Tingling around the mouth, fingers and toes: This can occur during the apheresis procedure due to the anticoagulant (blood thinner) used and is typically mild and temporary.
• Mild muscle cramps: Also caused by the anticoagulant used during apheresis and usually relieved with calcium replacement or by slowing the procedure.
• Bruising at the needle site: Minor bruising can happen where the needle is inserted and generally resolves on its own.
• Chills: Some donors experience temporary chills during the procedure.
• Decrease in blood platelet count: A temporary drop in platelet levels can occur but typically return to normal shortly after donation.

Donors are monitored closely by trained medical professionals throughout the donation process to ensure they are safe and comfortable.

Filgrastim is a medication given for several days before PBSC donation to increase the number of blood-forming cells in your bloodstream, and some donors experience temporary side effects while receiving the injections.

Side effects of filgrastim may include:

• Headaches: These can occur in the days leading up to collection and are temporary.
• Bone and muscle pain: This is one of the most common side effects and can feel similar to body aches from a cold or flu.
• Flu-like symptoms: Mild cold or flu-like discomfort may occur while receiving the injections.
• Nausea: Temporary nausea can occur during the injection period.
• Trouble sleeping or tiredness: Sleep disruption or fatigue may occur while your body responds to the medication.

Side effects related to filgrastim are almost always temporary and go away shortly after donation. Fewer than 1% of donors (about 0.6%) experience serious side effects.

PBSC donation is considered safe, but as with any medical procedure, there are potential risks. Fewer than 1% of donors experience a serious side effect from the process.

Recovery times vary depending on the individual and the type of donation, but donors can usually go back to work, school and most other activities within 1 to 7 days. Your blood stem cells return to normal levels within a few weeks.

After your donation, a volunteer courier delivers your blood stem cells to the patient in need. These cells will help rebuild the patient’s entire blood and immune system—a life-saving and life-changing gift.

Updates about and contact with your recipient is dependent on whether their transplant center is in the U.S. or international.

If it’s in the U.S., your donor center should be able to give you a brief update about your recipient's condition at four intervals: 9, 12, 18 and 30 months after transplant. During the first year after transplant, you'll also be able to communicate anonymously with your recipient. After that, if both parties are willing, you can have direct contact with your recipient—which could include meeting them in person.

If the patient’s transplant center is outside the U.S., you’ll need to follow their regulations for contact between donors and recipients. Some countries prohibit updates or contact at any time, while others allow it after a specified waiting period. Your donor representative should be able to provide more guidance.

While transplantation is a life-saving therapy, not all recipients survive. Sometimes a patient's body can’t withstand the pretransplant chemotherapy and radiation. Sometimes health complications occur after the transplant. But for many recipients, a transplant is successful and their best or only option. Your gift gives them hope and a second chance at life.