To determine the probability of which a child, during its lifetime, will need the umbilical cord blood is very difficult. On the assumption, that the spectrum of diseases would not enlarge and the incidence of tumours would not increase, the probability that a person becomes ill with one of diseases, in which the auto-transplant in its treatment could possibly be used is more than 15%. However only in a percentage of them is the transplantation therapy suitable. Today doctors have “for transplantation” the scale of the seriousness of the disease and on the scale “against the transplantation” the complications linked with transplantation. Autologous umbilical cord blood moves this decision towards the benefit of transplantation. Therefore also, the doctor’s decision for transplantation will be more frequent, in cases where the child will have the auto-transplant at its disposal. The aforementioned estimation doesn’t take into account experimental results, which show the utilisation of the stem cells of the umbilical cord blood, and not only for the recovery of the haematopoiesis. Here we don’t attempt any estimation. We can only state, that probably germinal cells from umbilical cord blood will be possible to differentiate to insulin producing cells, brain tissue cells, heart cells and probably to many others. If only a part of these experimental results would penetrate into the praxis in coming years, the reader himself can image the efficiency of the umbilical cord blood... If this will happen, nobody can say with certainty today. The problem is, if you expect a child, you must already decide now. To harvest and to store the umbilical cord blood is possible only at a child’s birth.