Several studies have suggested that there could be a link between the measles-mumps-rubella (MMR) vaccine and an increased risk of immune thrombocytopenic purpura.
Immune thrombocytopenic purpura, or ITP, is an immune system malfunction in which the body reacts to its own platelets as foreign invaders and destroys them.
An analysis of data from the Vaccine Safety Datalink, covering more than a million children who had received at least one MMR vaccination, showed that the proportion of ITP cases attributable to MMR exposure among children less than two years old ranged from 76 percent to 86 percent.