Anemia in Pregnancy: Diagnostic Thresholds and Management

Definition and Diagnosis

Anemia in pregnancy is defined as hemoglobin <11 g/dL in all trimesters, affecting a significant number of pregnant women globally and contributing to a substantial number of maternal deaths annually, according to the American College of Obstetricians and Gynecologists 1
Severe anemia is defined as hemoglobin <7 g/dL, moderate as 7-9.9 g/dL, and mild as 10-10.9 g/dL, as recommended by the American College of Obstetricians and Gynecologists 1
Fetal anemia is diagnosed when hemoglobin is >2 SD below the mean for gestational age, with severe fetal anemia defined as <0.55 multiples of the median, according to the American Journal of Obstetrics and Gynecology 2

The American College of Obstetricians and Gynecologists recommends screening all pregnant women at the first prenatal visit and again at 24-28 weeks gestation using hemoglobin or hematocrit testing 1
All pregnant women should receive 30 mg/day of elemental iron starting at the first prenatal visit, regardless of anemia status, as recommended by the American College of Obstetricians and Gynecologists 1

The American College of Obstetricians and Gynecologists recommends prescribing 60-120 mg/day of elemental iron orally as first-line treatment for mild to moderate anemia (Hb 7-10.9 g/dL) 1, 3
Ferric carboxymaltose is the preferred intravenous iron option due to rapid effectiveness and better tolerability, according to the American College of Obstetricians and Gynecologists 1, 4

Pregnancies with a fetus at significant risk for anemia should be delivered at 37-38 weeks gestation unless indications develop earlier, as recommended by the American Journal of Obstetrics and Gynecology 2
Monitor middle cerebral artery peak systolic velocity by Doppler to detect fetal anemia non-invasively, according to the American Journal of Obstetrics and Gynecology 2

The American College of Obstetricians and Gynecologists recommends continuing iron supplementation throughout pregnancy and the postpartum period to prevent recurrence 1, 3
Screen at 4-6 weeks postpartum using hemoglobin or hematocrit in at-risk women, as recommended by the American College of Obstetricians and Gynecologists 1, 4