Bone marrow donation is a procedure that provides life-saving blood-forming cells to individuals with diseases like leukemia, lymphoma, and other blood disorders. The process relies on finding a healthy, matching donor whose cells can rebuild a patient’s immune system. While countless people register with the hope of saving a life, several factors determine their eligibility. Among these, a potential donor’s age is a primary consideration for medical professionals and registries.
Age Requirements for Registries
National and international registries have specific age guidelines for individuals who wish to become potential bone marrow donors. In the United States, the NMDP (formerly Be The Match) registry focuses its recruitment on individuals between the ages of 18 and 40.
While recruitment is concentrated on this younger demographic, donation is not impossible after 40. Once an individual joins the registry, they remain listed as a potential donor until their 61st birthday. Transplant centers consistently select younger donors when given a choice, making the 18-to-40 group the most sought-after pool of candidates.
The guidelines are designed to maximize a successful outcome for the recipient while also ensuring the donation process is safe for the donor. Other registries may have slightly different ranges, with some accepting registrants up to age 55, but the preference for younger donors is a universal standard.
The Role of Age in Donation Success
The emphasis on younger donors is rooted in the biological quality of their hematopoietic stem cells. Cells from younger individuals are more robust and plentiful, a significant factor in transplant success. Studies show that patient survival rates are higher when the donor is younger, with one analysis finding that a patient’s two-year survival likelihood increases by about three percent for every 10-year decrease in a donor’s age.
A younger donor’s cells also reduce the risk of serious post-transplant complications. One of the most significant risks is graft-versus-host disease (GVHD), a condition where the donated immune cells attack the recipient’s body. Transplants from younger donors are linked to lower rates of both acute and chronic GVHD, improving the patient’s quality of life.
From the donor’s perspective, age is also a safety consideration. Younger individuals have fewer underlying health conditions and are at a lower risk of complications from the anesthesia and donation procedure. As people age, they are more likely to develop health issues that could make donation unsafe or delay a transplant when time is critical for the patient.
Exceptions to Standard Age Limits
Exceptions to registry guidelines can be made in certain situations. The most common involves directed donations, where a donor is a specific match for a family member. Approximately 30% of patients find a suitable donor within their family, and if the best match is a relative older than the registry limit, doctors may approve the donation if the individual is in excellent health.
For these directed donations, the transplant team makes the decision after a thorough medical evaluation, weighing the benefits to the patient against any risks to the donor. A healthy family member in their 60s might be cleared to donate if no younger, equally well-matched unrelated donor is found.
Another source of stem cells that bypasses donor age limits is umbilical cord blood. After a baby is born, the blood in the umbilical cord and placenta can be collected and stored. This cord blood is a rich source of hematopoietic stem cells and can be used for transplants in both children and adults. Since the cells are collected at birth, the donor’s age is not a factor.