Donating bone marrow is a relatively safe procedure. First, it may be helpful to read about the bone marrow collection process. It involves the removal of only a small proportion of the body’s marrow, and therefore has little if any effect on the donor. The donor’s body replaces the lost marrow within a few weeks.
The area where the bone marrow was taken may feel a little stiff and sore for a few days. It is also not uncommon to feel a little weak, although most donors are able to go back to their usual routine within a few days. There is also a small risk of problems associated with general anesthesia.
There are no long term side effects of bone marrow donation.
Clinical Bone Marrow and Blood Stem Cell Transplantation. Author: Kerry Atkinson and colleagues. Published by Cambridge University Press, 2003.