Umbilical cord blood is blood that remains in the placenta and in the attached umbilical cord after childbirth. Cord blood is obtained from the umbilical cord at the time of childbirth, after the cord has been detached from the newborn. Cord blood is collected because it contains stem cells, including hematopoietic cells, which can be used to treat hematopoietic and genetic disorders. Two decades ago, the first cord blood transplantation was performed for a child with bone marrow failure syndrome; the bone marrow simply stopped making cells. Success of this transplant opened many doors and possibilities for further research of cord blood. Learn more about cord blood research and how it is being used to treat numerous diseases such as lymphoma, with the most common being leukemia.