If a pregnant woman has low hemoglobin during pregnancy, it indicates anemia. This condition may be caused by unreasonable diet structure during pregnancy, lack of nutrition and iron deficiency; in addition, it is related to the increase of blood volume and blood thinning after pregnancy. Anemia will have an impact on the development of the baby and is also detrimental to the delivery of the pregnant woman. Therefore, if a pregnant woman has low hemoglobin, she needs to take appropriate blood supplements. For such pregnant women, it is also recommended to have a genetic diagnostic test for thalassemia to rule out thalassemia.