How does bone marrow donation work?

Bone marrow donation does not involve donating your actual bone. It involves the collection of blood stem cells which grow inside the bone. 

A bone marrow transplant infuses donated stem cells into a patient to replace diseased bone marrow and restore the healthy production of blood cells.  The infused stem cells locate the bone marrow cavity, and if the transplant is successful, begin to grow and produce healthy white and red blood cells and platelets.

In NZ, bone marrow can be donated in two ways:

1) Peripheral Blood Stem Cell collection (PBSC).  Stem cells are collected by a procedure called leukapheresis. A needle is inserted into a vein in the donors arm (similar to a blood donation) and a small amount of blood passes into a cell separator machine which separates and removes the stem cells. The rest of the blood is immediately returned to the donor. This procedure is performed at a hospital or a NZ Blood Service Donor Centre. It does not require a general anaesthetic and takes about three to four hours. Normally, a very small number of blood stem cells from the bone marrow circulate in your bloodstream. To increase this number, a hormone-like substance called G-CSF is injected under the skin daily for four days prior to the procedure.  After the procedure, the donor may go home but may be asked to undergo another collection procedure if insufficient cell numbers were collected.
What are the risks? G-CSF is usually well tolerated although during the course of the injections donors may experience bone pain and some flu-like symptoms, which usually respond to paracetamol. G-CSF has been used in patients for many years however the long-term effects of short treatments in normal donors is yet unknown.

2) Pelvic hip bone collection. Bone marrow can also be collected from the pelvic hip bone using a needle and syringe, under a general anaesthetic. This procedure can take up to two hours. Recovery time varies but usually donors can go home the next day and resume normal activities after two or three days. Bone marrow re-grows rapidly to replace the donated cells.
What are the risks? The risks of donating stem cells by this method are the same as the risks with any general anaesthetic. The chance of a serious complication in a healthy person is very low but some people may experience nausea, bruising and/or local pain and discomfort.

Umbilical cord blood is a third source of stem cells and refers to cells from the umbilical cord, which is normally discarded with the placenta when a baby is born.  This cord blood is a rich source of stem cells.  These cells can be extracted from the cord after the delivery of a baby and stored as a source of stem cells.  This process does not represent any risk to the baby or the mother or interfere with the birthing process.  There is currently no public cord blood bank in NZ. However NZ Bone Marrow Donor Registry has access to other cord blood banks around the world.

If you are chosen to donate stem cells for a patient you will be asked to visit a medical specialist who will carefully check your fitness to donate. The specialist will be a physician with a detailed knowledge of stem cells donation who works independently of the NZ Bone Marrow Donor Registry and the patient.