Umbilical cord blood banking is the practice of preserving foetal blood that remains in the umbilical cord at the time of birth for future use. PROSPECTIVE parents are often provided with information from various sources about different aspects of pregnancy, childbirth and infant care. Among them are materials about umbilical cord blood (UCB) banking for future use from commercial cord blood banks. The tag lines of these materials are appealing, for example, “The best gift you can give your baby”, “Cord blood cells may literally be life-saving to your child or family member”, etc. Some commercial cord blood banks have also periodically offered referral fees. Not only have obstetricians and midwives been approached directly by these banks, they also have to address this issue from parents who request that their baby’s cord blood be collected at the time of delivery and transported for storage. Banking an infant’s cord blood has implications. This article was written with the objective of providing information for prospective parents to make an informed decision. Umbilical cord blood There are three types of stem cells, ie. adult stem cells, human embryonic stem cells, and induced pluripotent stem cells. Adult stem cells are found all over the body, and can divide to form more adult stem cells or differentiate to specialised stem cells. Human embryonic cells originate from fertilised eggs, and can develop into any specialised cell. Induced pluripotent stem cells are formed by the reprogramming of adult cells that have already differentiated into specific cells, to develop into any type of specialised cells. The stem cells of the different tissues, and at different stages of development, vary in the number and types of cells that they can develop into. The ability of a stem cell to produce any cell type is gradually reduced as one gets older. In short, stem cells are master cells ”“ cells from which all other cells with specialised functions are created. The sources of stem cells are the fertilised egg, embryonic stem cells, and adult somatic stem cells found in the blood and bone marrow, brain, neural and other tissues. UCB contains haematopoietic stem cells (HSC), which are also found in the blood or bone marrow. However, cord blood HSC have greater proliferative and colony-forming capacities, and are more responsive to certain growth factors. In addition, they produce fewer complications that are associated with some aspects of HSC transplantation. Stem cell transplants There are two types of transplants ”“ allogeneic and autologous. Allogeneic transplants are collected from a related or unrelated donors, and transplanted into the patient after treatment of the cells. Autologous transplants are collected from the patient before treatment, and then re-infused after treatment into the same patient. Currently, haemopoietic stem cell transplants (HSCT) are the most established form of therapy. It involves the intravenous infusion of stem cells collected from bone marrow, peripheral blood or umbilical cord blood, to re-establish haematopoietic function in patients whose bone marrow or immune systems are damaged or defective. It is estimated that there are about 30,000-40,000 HSCT performed annually throughout the world, and that more than 20,000 people have survived five years or more after HSCT. HSCT is currently performed for patients with malignant and non-malignant blood disorders, solid organ tumours, and inherited metabolic and primary immunodeficiency diseases. The list of indications, hopefully, will continue to expand. UCB can be stored for non-directed donations, directed donations in at-risk families, and directed donations in low-risk families. All donations require compatibility (HLA) matching of donors with recipients. Non-directed donations are facilitated by the establishment of registries of bone marrow donors and UCB banks, which store the HLA data of donors and UCB. The registries and public UCB banks are involved in a global collaboration to find matches for patients worldwide. Directed donations are carried out for some families known to have genetic diseases that can be treated with HSCT. HLA-compatible UCB of a newborn may be used for an affected sibling. If not, it may be stored for possible use by a future HLA-compatible sibling. The use of assisted reproduction techniques to produce a “saviour sibling” is controversial, but is permitted in many developed countries. It is pertinent to know that improved chemotherapy techniques can “cure” about 80% of childhood leukaemia, which is one of the main uses of related UCB banking. The likelihood of directed donations in low-risk families is unknown. Their projected usages continue to remain speculative. Advantages and disadvantages of UCB The advantages include faster availability, as HSCT is carried out earlier than those receiving conventional bone marrow grafts; increase in the donor pool; lower incidence and severity of rejection; lower incidence of viral transmission; and lack of donor attrition, as bone marrow donors may change their address or may not be available with the passage of time. The disadvantages include relatively low numbers of stem cells in each UCB donation; lack of availability of subsequent stem cell donations when the HSCT fails or there is a relapse of the disease; and practical issues that may harm mother and/or baby’s health, as the collection has to be done in the third stage of labour when both mother and baby require one-to-one care. This occurs if there is any alteration of the normal management of the third stage to maximise UCB collection, eg withholding controlled cord traction in the presence of a postpartum haemorrhage, or if routine maternal or neonatal observations or investigations are neglected, overlooked or delayed. It is vital that the attending obstetrician or midwife’s attention is focused on minimising adverse outcomes in the newborn and postpartum haemorrhage, and not on collecting UCB. Some commercial UCB banks suggest that collection can be done by persons without a medical background, eg the spouse. This ignores the fact that UCB bacterial contamination rates are less with collection by experienced, trained staff, and that the adequacy of the volume collected is important. Problems may arise, especially in Caesarean sections, when the cord is wrapped around the neck, and in deliveries of premature babies or multiple pregnancies. These difficulties are more probable in directed donations in low-risk families. In the case of high-risk families, specific arrangements can be made to avoid harm to mother and/or baby. In the case of altruistic non-directed donations, there is no pressure to collect UCB from any individual delivery. Source
