Introduction
Anemia in pregnancy is a major global health problem. It is an important factor associated with an increased risk of maternal and neonatal morbidities such as reduced productivity at work, a higher risk of requiring a blood transfusion during delivery, intrauterine growth retardation, low birth weight, stillbirth and neonatal death. The prevalence of anemia in pregnant women in undeveloped or developing and developed countries is 52% and 20%, respectively. Regarding to the prevalence of anemia in Thai pregnant women, only about 20% of prevalence had ever been reported. The causes of anemia in pregnancy are physiology and pathology. However, iron deficiency, malarial parasite, deficiencies in folic acid and other micronutrients, sepsis, malignancy and human immunodeficiency virus (HIV) infection are the common pathologic cause.