Red cell mass increases in healthy pregnant women by 20 to 40% and plasma volume increases by 40 to 60 %. This imbalance leads to so called dilution anemia in pregnancy. The hemoglobin concentration decreases to 110 g/l and 100 g/l. The most common forms of anemia in pregnancy are iron and folic acid deficiency anemia. Other reasons of anemia including vitamin B12 deficiency are rare in pregnancy. Therapy consists of daily oral administration of 100 mg to 300 mg of elementary iron; parenteral iron therapy is given rarely. Folic acid deficiency is treated by daily administration of 5 mg to 20 mg of folic acid orally; the therapy should be started before conception in order to prevent anemia and neural tube defects. Transfusions of packed red cells to correct anemia in pregnancy are seldom given.