The 200th unit of blood collected from the umbilical cords and placentas of newborn babies was issued from the NHS' Cord Blood Centre in Edgware this week.

The centre, in Deansbrook Road, was opened in 1996 to process, test and store the blood after it is collected from patients in a selected few hospitals, including Barnet General.

The 200th unit was transplanted to a man in his 40s with leukemia, while the 199th unit went to a young baby with a severely impaired immune system.

The blood can be donated by mothers after the birth of their children and extracted in a harmless procedure. It is considered particularly useful because it contains a high proportion of stem cells.

Phyllis Teesdale, head of the NHS Cord Blood Bank, explains: "Cord blood can help many people because patients need a less close match than for bone marrow.

"Many mothers are now choosing to donate their cord blood so that it can help a patient desperately needing a transplant."

The hospitals where the blood is collected were chosen on the grounds of the large multi-ethnic mix of their patients, because there is a much better chance of patients finding a good match from donors of the same ethnic background.

Blood from the bank is now exported around the world and the first recpient of a transplant, a child suffering from leukemia in 1998, is alive and well today.