If I donate my baby's cord blood, can we get it back later if we need it?

Although a few such cases have actually happened, it is very very unlikely to get your cord blood back once it is donated. Donating cord blood is not a way of banking for your family for free.

When a mother signs the Informed Consent form to donate cord blood, she gives up any guaranteed access to that blood. First of all, the public bank may throw the blood out simply because it does not meet their size threshold, or simply because the paperwork is not complete. Secondly, even if the blood does make it into public storage, it may be released to some one else. 

Unlike organ donors, cord blood donors do not receive any priority treatment or waived fees if your child later needs a donor. The reward for donating cord blood is the possibility that your baby may Be The Match that saves a life.