Alternative to bone marrow grafts.
Presumed to have a low risk of transmitting CMV because of low rate of congenital CMV reported to be 0.2-2.5% of births in the U.S.
Can be evaluated for cellular content, infectious disease testing and HLA typing at the time of collection allowing for rapid availability once a unit is identified associated suitable for a patient.
The time to obtain a umbilical cord blood graft is much shorter than for obtaining an unrelated stem cell donor.
Transplantation tissue is frozen, is a small volume and is readily shipped worldwide.
HLA mismatching is well tolerated, with a lower than expected incidence of graft vs host disease.
Cell dose is limited to what is present in an individual unit.
Usually not sufficient for an adult weighing more than 50 kg.
There are no additional donor lymphocytes available to utilize in the event of slow engraftment or disease relapse.