ND, United States
North Dakota does not have any state legislation around cord blood education, but their Dept. of Health has officially adopted the educational materials from Parent's Guide to Cord Blood Foundation.
- Once we have stored cord blood for our family, how long should we keep it?
- Indefinitely. From an economic perspective, it does not make sense to invest in the up-front processing fee and pay for years of annual storage, and then throw out the investment. That would be like buying life insurance and then cancelling it because you have not died yet. Especially given that the probability of some one in the immediate family needing a transplant increases with age. Even if the cord blood collection was small, and the child becomes too large to use it for a transplant, it could still be enough cells for a regenerative medicine therapy. The science of cryobiology tells us that cells which are cryogenically preserved remain viable for decades. It has been confirmed that cord blood stem cells were still viable after being frozen 23+ years.
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- What fraction of cord blood donations get accepted?
Between a half and three quarters of donations are discarded. The primary reason is that the collection volume is too small. Public banks will only save a collection that is big enough to transplant a large child or small adult.
- How much cord blood is needed for a transplant?
The crucial thing is not the volume of the cord blood collection, but the number of stem cells it contains. Transplant doctors develop recommendations based on the Total Nucleated Cell count, or TNC, because it is the easiest measure to reproduce between different labs. For treating cancer, the transplant dose should be at least 25 million TNC per kilogram of patient body weight (1 kilogram equals 2.2 pounds). The average cord blood collection holds 8.6 million TNC per mL. Thus, the optimal transplant dose requires harvesting:
1.3 mL of cord blood for every pound of patient weight, -or-
2.9 mL of cord blood for every kg of patient weight
However, as more transplant centers are adopting the practice of giving adult patients "double cord blood transplants" with two cord blood units, it is less critical for both units to have adequate cell dose.
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