In the final stages of pre bone marrow transplant screening (donation end for me, not receiving, thankfully!), the "kit" for the samples came in it's own carrier bag, and it was pretty well filled. The blood had to be drawn by my GP, who was supposed to include some counselling in that stage of the process. The extent of the counselling went something like,......
"So, here we go. Don't for an instant think about telling me you have doubts about this whole thing."
Fortunately, I was not having doubts at all, but it struck me it might have been easier to just donate a pint of blood and let them divide it up in their own time. Fortunately, I have blood vessels like the Channel Tunnel.