Treatment for Iron Deficiency Anemia in Third Trimester Pregnancy

Diagnosis Confirmation

A presumptive diagnosis of iron deficiency anemia can be made based on low hemoglobin or hematocrit values appropriate for the stage of pregnancy, if the woman is not acutely ill 2, 1
The prevalence of iron deficiency in pregnant women increases significantly in the third trimester, affecting up to 29.5% of women 3

Oral iron supplementation at 60-120 mg/day of elemental iron is the recommended first-line treatment 2, 1
Treatment should be accompanied by dietary counseling to increase consumption of iron-rich foods and foods that enhance iron absorption 2, 1

Monitor response to treatment after 4 weeks 2, 1
An adequate response is defined as a hemoglobin increase of ≥1 g/dL or hematocrit increase of ≥3% 2, 1
If anemia persists despite compliance with oral iron, further evaluation with additional laboratory tests may be needed, including mean corpuscular volume (MCV), red cell distribution width (RDW), and serum ferritin 2

The Centers for Disease Control and Prevention (CDC) recommends iron supplementation, but the U.S. Preventive Services Task Force (USPSTF) found insufficient evidence to determine the balance of benefits and harms of iron supplementation during pregnancy 4

Physiologic anemia of pregnancy (hemodilution) is normal during pregnancy and should not be confused with iron deficiency anemia 3
Anemia in the third trimester may not be associated with the same adverse outcomes as anemia in early pregnancy 5, 3
When using serum ferritin to diagnose iron deficiency during pregnancy, remember that ferritin is an acute phase reactant and may be elevated during inflammation, potentially masking iron deficiency 3
In women of African, Mediterranean, or Southeast Asian ancestry, mild anemia unresponsive to iron therapy may be due to thalassemia minor or sickle cell trait 2