Signing up to be a bone marrow donor takes about 10 minutes online and costs nothing. You order a free cheek swab kit, mail it back, and your tissue type gets added to the national registry. From there, you wait to see if you ever match with a patient who needs a transplant. Here’s what the full process looks like, from registration to donation.
How to Join the Registry
The National Marrow Donor Program (NMDP), which runs the Be The Match registry, handles the entire process by mail. There are two steps:
- Order your free swab kit. On the NMDP website, you’ll answer a few screening questions to confirm eligibility, then provide a mailing address. The kit typically arrives in 3 to 7 days.
- Swab your cheeks and mail it back. The kit includes simple instructions and a prepaid return envelope. Once the lab processes your samples, your tissue type is added to the registry and can be searched against patients worldwide who need a transplant.
That’s it for the signup. You may never be contacted, or you could get a call months or years later saying you’re a potential match. Your body has 12 unique HLA markers (proteins on your cells that your immune system uses to tell “self” from “foreign”), and the possible combinations number in the millions. Finding a close match is rare, which is why the registry needs as many people as possible.
Who Can Sign Up
You need to be between 18 and 40 to join the registry, though NMDP actively recruits donors ages 18 to 35. Medical research shows younger donors produce better outcomes for patients, so doctors prefer them when multiple matches exist. You also need to be in generally good health and willing to donate to any patient in need.
Certain health conditions can disqualify you, either at signup or later. If you develop a significant condition like heart disease, diabetes, or hepatitis after joining, you’re expected to update your information on the registry. The screening questions during signup will flag most common disqualifiers before you even order a kit.
Why Diverse Donors Are Needed
HLA markers are inherited, so your best chance of matching someone is usually within your own ethnic background. Non-Hispanic White patients are significantly more likely to find a high-quality match on the registry compared to other racial and ethnic groups. While recent research confirms that patients from all backgrounds can find a donor at lower match thresholds, the gap at the highest match levels is real. If you’re Black, Hispanic, Asian, Native American, or multiracial, your registration is especially valuable because those populations are underrepresented.
What Happens If You Match
If a patient’s medical team identifies you as a potential match, a coordinator will contact you to discuss next steps. You’ll go through additional blood testing, a physical exam, and a health screening to confirm the match and make sure donation is safe for you. This process can take several weeks.
There are two ways donation actually happens, and the patient’s doctor chooses the method based on what’s best for the patient.
About 90% of donors give through a non-surgical process called PBSC (peripheral blood stem cell) donation. For five days beforehand, you receive injections of a medication that encourages your body to push blood-forming stem cells out of the bone marrow and into your bloodstream. On donation day, blood is drawn from one arm, run through a machine that filters out the stem cells, and returned to your body through your other arm. The procedure is similar to donating plasma or platelets and takes several hours as an outpatient.
The remaining 10% of donors go through a surgical bone marrow harvest. Under general anesthesia, doctors use a needle to collect liquid marrow from the back of your hip bone. This is a same-day surgery in most cases.
Recovery After Donation
Recovery depends on which method you undergo. For bone marrow harvest, the total recovery process typically takes 2 to 6 weeks. You’ll likely feel soreness at the collection site, especially when bending or walking, for the first several days. That pain usually fades within 6 to 12 weeks. Your bone marrow replenishes itself within a few weeks, and once it does, most fatigue and soreness resolve. Side effects of the surgery can include nausea from anesthesia, headache, dizziness, and in rare cases, infection or prolonged bleeding at the collection site.
PBSC donation generally involves a shorter recovery. The most common side effects come from the five days of injections before the procedure, which can cause bone pain, headaches, and fatigue. These typically resolve within a day or two after donation.
Costs and Time Off Work
Donation costs you nothing. All medical expenses related to donation, including lab tests, physical exams, and the procedure itself, are covered by the NMDP. You’ll receive a donor medical services card to present at appointments instead of your personal insurance. If you mistakenly receive a bill for any donation-related care, you’re instructed not to pay it yourself but to forward it to your coordinator for resolution. Medical coverage extends up to $1,000,000 for any injury directly related to the donation procedure, covering treatment for up to 260 weeks.
Travel is also handled for you. Your coordinator arranges and pays for airfare (for you and a companion), hotel accommodations, and reimburses mileage if you drive. Meals are covered up to $80 per person per day, broken down as $15 for breakfast, $20 for lunch, and $45 for dinner. Parking, tolls, taxis, and even shuttle tips at 15% are all reimbursable.
If taking time off work is a concern, the NMDP can help. Coordinators will work with your employer or reimburse you directly for lost wages during donation-related activities. If donation leads to any temporary or permanent loss of work, disability support is available up to $1,000,000, provided you submit documentation of your job and wage loss.
What Staying on the Registry Means
Once you join, you stay on the registry until age 61. During that time, the most important thing you can do is keep your contact information current. If you match a patient, their medical team needs to reach you quickly. A match that can’t be contacted is effectively a match that doesn’t exist. You can update your address, phone number, and health status through your Be The Match account at any time.