This section provides at-a-glance statistics about the blood stem cell donor registry in the United States. It also contains statistics about the number of blood stem cell transplants and transplant outcomes.
Statistics at a glance
Fiscal Year 2025: October 1, 2024 – September 30, 2025:
- The C.W. Bill Young Cell Transplantation Program (CWBYCTP) donor registry contains more than 9.4 million potential adult donors in the United States
- More than 247,900 cord blood units are available on the CWBYCTP registry.
- More than 129,700 cord blood units have been collected through the National Cord Blood Inventory (NCBI) Program, with more than 3,900 NCBI units added in Fiscal Year 2025.
- The CWBYCTP facilitated over 8,400 unrelated blood stem cell transplants, including over 7,200 for patients in the United States.
Fiscal Year 2026 Year to date: January 1, 2026 – March 31, 2026:
- More than 36,000 new adult donor registrants from genetically varied backgrounds have been added to the CWBYCTP donor registry.
- More than 8,900 patients have searched the CWBYCTP Registry for a suitably matched adult donor or cord blood unit.
- The CWBYCTP facilitated over 4,400 unrelated blood stem cell transplants, including over 3,800 for patients in the United States.
More than 3.7 million volunteers on the registry in 2025 were from genetically varied communities.
Figure 4. Genetic Variability of Marrow Donors on the Registry
Figure 5. Marrow Donors on the Registry by Genetic Variability
More than 130,000 cord blood units on the registry in 2025 were from genetically varied backgrounds.
Figure 6. Cord Blood Units on the Registry by Ancestry
View more data and figures on the Donor Registry Data page.
AdA total of 22,579 hematopoietic cell transplantations (HCTs), also called blood stem cell transplants, were performed in the United States and reported to the Center for International Blood and Marrow Transplant Research (CIBMTR) in 2024. Of these, 6,646 (29%) were unrelated transplants and 3,756 (17%) were related transplants.
Peripheral blood stem cells (PBSC) were the most frequently used cell source for all patients in 2024. Bone marrow was used more frequently in patients whose donor was related to them than patients who had an unrelated donor transplant. Umbilical cord blood was used more for patients who had an unrelated donor.
| Donor Type | Peripheral Blood | Marrow | Cord Blood |
|---|---|---|---|
| Related Donor | 77% | 23% | <1% |
| Unrelated Donor | 86% | 10% | 5% |
View the report on transplants performed.
Use the Transplant Center Search tool to find out about the number of transplants performed for certain diseases or transplant centers.
Data collected by the CIBMTR (including data used to meet Stem Cell Therapeutic Outcomes Database (SCTOD) requirements) are used to provide patient survival estimates for a disease at a specific center and also to develop summary slides of outcomes data. The Hematopoietic Cell Transplant (HCT) Indications and Outcomes page shows the disease-specific indications and outcomes, as well as comparison of HCT outcomes and trends by age, disease stage, and transplant type.
Use the Transplant Center Search tool to review the “Overall center survival” tab for each transplant program and find out about the patient’s survival information for a particular center.
To understand how information from a report applies to your specific situation, talk with your doctor.
If the data needed are not available through these reports, you can submit a customized data request using a CIBMTR Data Request Form.