Anemia is a condition in which blood has a lower-than-normal amount of red blood cells or hemoglobin. Anemia in pregnancy is a decrease in the total red blood cells (RBCs) or hemoglobin in the blood during pregnancy. Anemia is an extremely common condition in pregnancy world-wide, conferring a number of health risks to mother and child. While anemia in pregnancy may be pathologic, in normal pregnancies, the increase in RBC mass is smaller than the increase in plasma volume, leading to a mild decrease in hemoglobin concentration referred to as physiologic (or dilutional) anemia. Maternal signs and symptoms are usually non-specific, but can include: fatigue, pallor, dyspnea, palpitations, and dizziness. There are numerous well-known maternal consequences of anemia including: maternal cardiovascular strain, reduced physical and mental performance, reduced peripartum blood reserves, increased risk for peripartum blood product transfusion, and increased risk for maternal mortality. Signs and symptoms Common symptoms are headache, fatigue, lethargy, tachycardia, tachypnea, paresthesia, pallor, glossitis and cheilitis. Severe symptoms include congestive heart failure, placenta previa, abruptio placenta, and operative delivery. Causes In the simplest of terms, anemia results from impaired production of red blood cells, increased destruction of red blood cells or blood loss. Anemia can be congenital (i.e. conditions such as sickle cell anemia and thalassemia) or acquired (i.e., conditions such as iron-deficiency anemia or anemia as a result of an infection). The causes of anemia during pregnancy can be subdivided into two main categories; physiologic and non-physiologic causes. Physiologic Causes Dilutional anemia: There is an increase in overall blood volume during pregnancy, and even though there is an increase in overall red blood cell mass, the increase in the other parts of the blood like plasma decrease the overall percentage of red blood cells in circulation. Non-physiologic Causes Iron deficiency anemia: this can occur from the increased production of red blood cells, which requires a lot of iron and also from inadequate intake of iron, which increase in pregnancy. Hemoglobinopathies: Thalassemia and sickle cell disease Dietary deficiencies: Folate deficiency and vitamin B12 deficiency are common causes of anemia in pregnancy. Folate deficiency occurs due to diets low in lefty green vegetables, and animal sources of protein. B12 deficiency tends to be more common in individuals with Crohn's disease or gastrectomies. Cell membrane disorders: Hereditary spherocytosis Autoimmune causes: lead to the hemolysis of red blood cells (Ex: autoimmune hemolytic anemia). Hypothyroidism and chronic kidney disease Parasitic