Most platelet donations are given to patients who are unable to make enough platelets in their bone marrow. For example, patients with leukaemia or other cancers may have too few platelets as the result of their disease or treatment. Also after major surgery or extensive injury, patients may need platelet transfusions to replace those lost through bleeding. Platelets are often life-saving and special in that they can help up to 3 adults or even 12 children. As platelets can only be stored for a few days, regular and frequent donors are in great demand and that is why platelet donors are asked to attend at least 8 - 10 times per year.