Ensuring the safety of goodwill donors is the priority when conducting bone marrow transplants, according to officials of the Japan Marrow Donor Foundation.

A bone marrow donation, unlike giving blood, is a difficult procedure that places a large burden on the donor.

In the procedure, 500cc to 800cc of bone marrow is drawn from the donor's hip via a number of special needles. It is then injected into one of the recipient's veins.

Donors are given a general anesthetic and feel no pain during the procedure, which usually requires a four-day hospital stay, including a two-day rest after the extraction procedure.

After the extraction, most donors experience only a dull pain, which usually quickly subsides. But in some cases, donors suffer back pain for up to several months after leaving hospital.

Other donors have faced even more serious consequences. In 1998, a donor contracted hepatitis C in the form of an infection picked up in the hospital. And in 2000, another donor developed a large hematoma in the abdomen.

In 1990, a male donor died of anesthesia-related complications while attempting to save his twin brother.

To ensure the safety of donors, the marrow donor foundation, established in 1991, has a patients' safety committee, headed by Yasutaka Hoshi, a professor at Jikei University School of Medicine.

Under committee guidelines, only qualified medical institutions are permitted to conduct the procedure.

And donors can at least take heart from the assurance that if any complications arise during the marrow donation procedure, they are eligible for up to 100 million yen in compensation.