Aplastic anemia is a condition that occurs when your body stops producing enough new blood cells. The condition leaves you fatigued and more prone to infections and uncontrolled bleeding.A rare and serious condition, aplastic anemia can develop at any age. It can occur suddenly, or it can come on slowly and worsen over time. It can be mild or severe.Treatment for aplastic anemia might include medications, blood transfusions or a stem cell transplant, also known as a bone marrow transplant.