Cord blood, due to its relatively limited stem cell count, is primarily utilized for pediatric patients. For adult recipients, particularly those with higher body weight, successful transplantation may sometimes necessitate the use of two or more cord blood units. While an ideal stem cell source is characterized by high tissue-type compatibility, cord blood transplants offer a distinct advantage: they can be successfully performed even with a lower degree of HLA matching. Furthermore, as cord blood units are readily cryopreserved and available, they are often the preferred option for urgent transplantation needs. Ultimately, the decision regarding the most suitable stem cell source rests with the transplant team, based on the individual patient's condition and specific requirements.