One of the most serious explanations for bleeding gums is a bleeding disorder, such as idiopathic thrombocytopenic purpura (ITP). With ITP, bleeding and bruising are just signs of your blood's inability to clot, so your gums and mouth are frequently the first place where symptoms appear. Along with bleeding, you might also notice pinpoint bruises on your gums and frequent nosebleeds.
With proper treatment, ITP is usually manageable and is rarely fatal. However, if bleeding gums cause you to believe that you have ITP or any other bleeding disorder, talk to your dentist, who may refer you to a specialist [source: National Heart Lung and Blood Institute].
Whatever the reason for your bleeding gums, it's important to get to the root cause of the problem. Yes, it could be a symptom of a more serious underlying issue, but no matter what, it's uncomfortable and needs to be taken care of. Make an appointment to see your dentist as soon as you start seeing red.