transitive verb. 1  To keep up or carry on; continue: maintain good relations. 2  To keep in an existing state; preserve or retain: maintain one's composure. 3  To keep in a condition of good repair or efficiency: maintain two cars.
Anemia is usually classified based on the size of RBCs, as measured by the mean corpuscular volume (MCV). Anemia can be microcytic (MCV typically less than 80 Î¼m3 [80 fL]), normocytic (80 to 100 Î¼m3 [80 to 100 fL]), or macrocytic (greater than 100 Î¼m3 [100 fL]).
Causes of anemia. Different types of anemia and their causes include: Iron deficiency anemia. This is the most common type of anemia worldwide. Iron deficiency anemia is caused by a shortage of iron in your body. Your bone marrow needs iron to make hemoglobin. Without adequate iron, your body can't produce enough hemoglobin for red blood cells. Without iron supplementation, this type of anemia occurs in many pregnant women. It is also caused by blood loss, such as from heavy menstrual bleeding, an ulcer, cancer and regular use of some over-the-counter pain relievers, especially aspirin. Vitamin deficiency anemia. In addition to iron, your body needs folate and vitamin B-12 to produce enough healthy red blood cells. A diet lacking in these and other key nutrients can cause decreased red blood cell production. Additionally, some people may consume enough B-12, but their bodies aren't able to process the vitamin. This can lead to vitamin deficiency anemia, also known as pernicious anemia. Anemia of chronic disease.