I don’t know. I’ve never seriously considered it. But Clay Jones at Science-Based Medicine has.
A fairly recent addition to the long list of choices that [new] parents are burdened with, thanks to a push from reputable organizations like the American Academy of Pediatrics, as well as private companies looking to turn a profit, is what to do with the blood in their newborn infant’s umbilical cord.
Currently the most commonly-chosen option remains to simply leave it in there. In that case, it will be discarded along with the mother’s placenta or even occasionally eaten although that is a topic for another post perhaps. Another option is to have blood from the umbilical cord donated to a public cord blood bank. These have been popping up all over the place and public banking is currently recommended by the American Academy of Pediatrics whenever possible. The final option, which is by far the most controversial (and expensive), is paying to have the umbilical cord blood banked privately for personal use by the donating child or a family member.