Donating bone marrow stem cells requires agreeing to have stem cells drawn from either your blood or bone marrow to be given to someone else. This is known as a stem cell transplant, bone marrow transplant or hematopoietic stem cell transplant.

Stem cells used in transplants come from three sources. These sources are the spongy tissue at the center of some bones (bone marrow), the bloodstream (peripheral blood) and umbilical cord blood from newborns. The source that's used depends on the purpose of the transplant.

In the past, surgery to draw bone marrow stem cells from bone marrow was the only way to collect stem cells. Today, however, it's more common to collect stem cells from blood through a vein (peripheral blood stem cell donation).

Umbilical cords produce only a small amount of blood, which might not be enough for an adult. This type of transplant is generally used for children and small adults.

Bone marrow transplants are lifesaving treatments for people with diseases such as leukemia, lymphoma, other cancers or sickle cell anemia. Donated blood stem cells are needed for these transplants.

You might consider donating blood or bone marrow because someone in your family needs a stem cell transplant and health care providers think you might be a match for that person. Or perhaps you want to help someone else — maybe even someone you don't know — who's waiting for a stem cell transplant.

Pregnant women might consider storing the stem cells that remain in the umbilical cord and placenta after birth for their children's or someone else's future use, if needed.

Bone marrow donation

Bone marrow stem cells are collected from a section of the pelvic bone under general anesthesia. The most serious risk associated with donating bone marrow involves the use and effects of anesthesia during surgery.

The surgery might cause tiredness, weakness, and mild back or hip pain. Pain relievers such as acetaminophen (Tylenol, others) or ibuprofen (Advil, Motrin IB, others) might help. You'll likely be able to get back to your routine within a couple of days. But it may take a couple of weeks before you feel fully recovered.

Peripheral blood stem cell donation

The risks of this type of stem cell donation are minimal. The injection that increases the number of stem cells in the blood can cause side effects, such as bone pain, muscle aches, headache, fatigue, nausea and vomiting.

Other possible side effects include being lightheaded or having chills, numbness or tingling around the mouth, and cramping in the hands. Side effects usually disappear within a couple of days after the injections stop.

If you want to donate stem cells, talk to your health care provider or contact the National Marrow Donor Program. This is a federally funded nonprofit organization that keeps a database of people willing to donate.

If you decide to donate, you'll learn about the process and possible risks of donating. If you want to continue with the process, a blood or tissue sample can be used to help match you to someone who needs a stem cell transplant. You'll also be asked to sign a consent form, but you can change your mind at any time.

Next comes testing for human leukocyte antigen (HLA) typing. HLAs are proteins found in most cells in your body. This test helps match donors and recipients. A close match increases the chances that the transplant will be a success.

Donors who are matched with someone who needs a blood stem cell transplant are then tested to make sure they don't have genetic or infectious diseases. The testing helps ensure that the donation will be safe for the donor and recipient.

Cells from younger donors have the best chance of success when transplanted. Health care providers prefer donors to be ages 18 to 35. Age 40 is the upper limit for joining the National Marrow Donor Program.

The costs related to collecting stem cells for donation are charged to people needing transplants or their health insurance companies.

Bone marrow donation

Collecting stem cells from bone marrow is a type of surgery done in the operating room. Anesthesia is used for the procedure to keep donors from feeling pain. Needles are inserted through the skin and into the back of the pelvic bone to draw the marrow out of the bone. This process usually takes 1 to 2 hours.

After bone marrow collection, donors go to the recovery room, where they are monitored. Occasionally, donors stay overnight.

Peripheral blood stem cell donation

For donation of blood stem cells, donors receive injections of medication that are given under the skin (subcutaneously). The medication increases the number of blood stem cells in the bloodstream. The medication is usually started several days before donation.

During the donation, blood is usually taken through a tube (catheter) in a vein in an arm. The blood goes through a machine that takes out the stem cells. The blood is then returned to the donor.

This process is called apheresis. It is an outpatient procedure that typically takes up to 4 to 6 hours to complete. Some donors require multiple apheresis sessions, depending on how many blood stem cells are needed.

After the procedure

Recovery times vary depending on the individual and type of donation. But most donors can return to their usual activities within days to weeks after donation.

Becoming a donor is a serious commitment. It's difficult to predict the outcome for someone who receives the donation, but it's possible your donation can help save a life.