Giving Hope A Chance
Q&A with Dr Yvonne Loh

Dr Yvonne Loh is a blood stem cell transplant physician at the Singapore General Hospital, is a volunteer donor and sits on the board of the BMDP as a volunteer. Working with patients with blood diseases such as leukaemia and lymphoma she speaks about what it means to be a bone marrow donor.

Q: Why are bone marrow transplants needed?


When a person suffers from leukaemia or other deadly blood-related diseases, sometimes the best chance for a cure is through a bone marrow or blood stem cell transplant.


Q: What are the chances of finding a donor within the family?


Family sizes in Singapore are getting smaller, and fewer patients have a brother or sister who may serve as a suitable blood stem cell donor. Only a third of patients will find a suitable donor amongst their siblings. Parents are usually not suitable donors for their children because each child inherits half their set of genes from each parent. Consequently, more than half our stem cell transplants today are between unrelated donors.


Q: How does one sign up as a donor?


A simple buccal swab is all that’s needed to sign up to the registry. The swab is a painless way to collect DNA from the cells from a person’s cheek. The DNA information is then recorded in the registry. If you’re found to be a match to a patient, the BMDP will contact you to donate.


Q: What is the procedure for a bone marrow transplant?


If you are found to be a potential match for a patient, BMDP will contact you – possibly years after you first signed up. You will then take a blood test to confirm that you are indeed a match. If so, BMDP will arrange for a medical check-up and blood tests to ensure you are healthy to donate. The donation process can be either from a vein in your arm or from the pelvic bone; the doctor who does your medical check-up will discuss the alternatives with you. Once you have given your consent and are deemed healthy to donate, a date will be fixed for the donation, which will coincide with the transplant process in the patient


The recipient will undergo chemotherapy and/or radiation therapy, making his/her blood counts fall very low in preparation to receive your blood stem cells. When these have been collected from you, they are infused into the patient through his/her vein. After around 2 to 3 weeks, these will grow into new red blood cells, white blood cells and platelets derived from you.


Family sizes in Singapore are getting smaller, and fewer patients have a brother or sister who may serve as a suitable blood stem cell donor.

- Dr Yvonne Loh

 Q: What are the risks to a donor?

Bone marrow harvesting or peripheral blood stem cell harvesting are very safe procedures. For bone marrow harvests, the risks to the donor are mild, rare and self-limiting.


Q: Will a donor be asked to donate again after the procedure?

It is uncommon for a donor to be called on to donate to the same patient again. The instances of this being required are either because the initial collection was insufficient or the patient’s blood counts are not recovering. More commonly, it is because the patient has relapsed and may require another transplant or for a portion of the donor’s cells (called lymphocytes) to bolster his immune system to fight away cancer cells. In general, it will be safe to donate again after a period of 3 months. You will be assessed for fitness to donate, and it will strictly be on a voluntary basis should you agree to donate again


Q: What is the recovery period?

In general, after a bone marrow harvest, there will be soreness over the lower back for approximately one week. Most donors are able to walk readily the day of the harvest. For peripheral blood stem cell harvest, donors will feel tired during the days of the collection, but would recover within 1-2 days. Within 2 weeks of donation, most donors’ blood cell counts would have returned to normal. Whatever blood stem cells were donated would be regenerated by the body.

PUBLISHED ON 26 April 2012
Registering to become a bone marrow donor means committing to be there when you get the call to give life. Each registrant provides hope for those waiting. A person could, however, be a match within a few months of registering, a year later or even seven years later.
How to register?