The risk to the donor is quite low. It requires general anestesia, and so a night in the hospital. But serious complications have a probability of 1:20000 (wiki

The risk to the donor is quite low. It requires general anestesia, and so a night in the hospital. But serious complications have a probability of 1:20000 (wikipedia German). The english article gives some more differentiated figures. The spine is not invaded, the "marrow" means technically stem cells extracted from blood, in most cases. http://en.wikipedia.org/wiki/Marrow_Transplantation#Risks_to_donor http://en.wikipedia.org/wiki/Marrow_Transplantation#Risks_to... I'm not a doctor.