The Next Generation Umbilical Cord Blood Program Frequently Asked Questions Cord blood, or umbilical cord blood, is blood that remains in the umbilical cord and placenta at the time of birth. Stem cells are the building blocks of our blood and immune systems. They form the white cells that fight infection, the red cells that carry oxygen and platelets that promote healing. Stem cells are normally found in our bone marrow and even, to a much lesser extent, in our circulating blood, where they continue to generate cells throughout our lives. Like bone marrow, cord blood is rich in stem cells.
Stem cells are the essential element in successful bone marrow transplants.
Previous exposure to diseases can make bone marrow from an adult more difficult to use in transplantation. After a baby is born, the umbilical cord is clamped, breaking the link between the baby and the placenta. The small amount of blood in the cord is drained and taken to a cord blood bank. There, the blood cells are tissue typed and entered into the NMDP database. The blood is then frozen for later use.