As parents, we always want to prepare more for our children and not let them lose to the starting line. After the birth of a baby, many parents want to save a copy of the cord blood for their child. Is it necessary to do so? Is cord blood useful? I believe this is the most important question parents of newborns want to know. Cord blood is the blood that exists in the umbilical cord and placenta after the fetus is born, the cord is ligated and severed. In the past, cord blood was discarded, but medical research in recent decades has shown that it contains all the components of normal blood, and is especially rich in hematopoietic stem cells, which can be used for transplantation to rebuild the body’s hematopoietic and immune systems and treat many serious diseases. This shows that its preservation is of great value. The specific functions of cord blood are: a. Cord blood contains a large number of stem cells, which are the seeds of life and are able to differentiate various cells in the human body to form important cells such as blood cells, nerve cells, bone cells, etc. Therefore, the treatment of diseases is also its main function. Secondly, stem cells are also self-renewing and can highly proliferate and have several differentiation potentials. They can divide to maintain the characteristics and number of their own cells, and can further differentiate into various tissue cells, which can help repair body tissues. Third, cord blood is rich in hematopoietic stem cells, which can help rebuild the body’s hematopoietic and immune systems. Transplanting hematopoietic stem cells through cord blood can help us treat the hematological system, immune system, and genetic-metabolic and congenital diseases. Cord blood has been used to treat more than 80 diseases such as leukemia, metabolic diseases, thalassemia, pernicious tumors, and primary immunodeficiency diseases. It can be said that cord blood is useful and it is best to save a copy for your baby in case of future needs. Collection needs to be done by professionally qualified healthcare professionals, and cord blood is collected after the baby is born using a sealed blood bag containing an anticoagulant.