Blood stem cell donation ​FAQs

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 through our research collaboration CIBMTR® 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 Donor for All, means more transplants for patients and more opportunities for NMDP Registry members to donate!

Age also plays a role. Doctors request donors between 18 and 35 nearly 80% of the time, because research shows that younger donors' cells lead to better long-term outcomes for patients.

If you match a patient, 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.

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:

• Bone Marrow Donation 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.
• 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.

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
• donation itself
• travel expenses such as hotel, 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.

Marrow donation is primarily done under general anesthesia, so the donor experiences no pain during the collection procedure.

Discomfort and side effects vary from person to person. Most marrow donors experience some side effects after donation. Common side effects include:

• Back or hip pain
• Fatigue
• Muscle pain
• Headache
• Bruising at the incision site

Some people compare the discomfort to soreness after a fall or a strained muscle. For most, the side effects last a few days to 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.

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.
• 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 aid 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.

Donors may experience symptoms such as but not limited to, headaches or bone and muscle pain, similar to a cold or the flu, for several days before collection. These are side effects of the filgrastim injections and disappear shortly after donation. Other common side effects are nausea, trouble sleeping and tiredness. Less than 1% (0.6%) of donors experience serious side effects from filgrastim.

The PBSC donation procedure can also have side effects. Some donors experience tingling around the mouth, fingers and toes and mild muscle cramps. This is caused by the anticoagulant (blood thinner) used in the apheresis procedure. These symptoms are easily treated with calcium replacement or by slowing down the procedure. Other common side effects include bruising at the needle site, chills and a decrease in the blood platelet count.

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.