Anemia in Pregnancy: ACOG Practice Bulletin Summary, Number 233.

Anemia, the most common hematologic abnormality, is a reduction in the concentration of erythrocytes or hemoglobin in blood. The two most common causes of anemia in pregnancy and the puerperium are iron deficiency and acute blood loss. Iron requirements increase during pregnancy, and a failure to maintain sufficient levels of iron may result in adverse maternal-fetal consequences. The purpose of this document is to provide a brief overview of the causes of anemia in pregnancy, review iron requirements, and provide recommendations for screening and clinical management of anemia during pregnancy.