Iron Deficiency Anemia in Pregnancy

Diagnosis and Prevalence

Iron deficiency causes symptoms before anemia develops, including impaired neurocognitive function, mood disturbances, and dizziness, even when hemoglobin remains above diagnostic thresholds for anemia 1
The prevalence of iron deficiency in pregnant women is 18.6%, with only 16.2% meeting criteria for anemia, meaning standard hemoglobin screening may miss the diagnosis 2, 3, 1
Iron deficiency prevalence increases as pregnancy progresses, with rates climbing from 6.9% in the first trimester to 29.5% in the third trimester 5

The American Academy of Family Physicians recommends screening with hemoglobin/hematocrit immediately, though it may miss iron deficiency without anemia 2, 6, 7
The American College of Obstetricians and Gynecologists defines anemia as hemoglobin <11 g/dL in all trimesters 7
The Centers for Disease Control and Prevention recommends considering serum ferritin if hemoglobin is normal, as low ferritin indicates iron deficiency even without anemia 5, 1

The American Academy of Family Physicians recommends prescribing 60-120 mg elemental iron daily for confirmed anemia (Hb <11 g/dL) 2, 6, 8, 7
The American College of Obstetricians and Gynecologists recommends starting 30 mg elemental iron daily for iron deficiency without anemia 2, 3, 7
The Centers for Disease Control and Prevention recommends reassessing in 4 weeks, with expected increases in hemoglobin by 1 g/dL or hematocrit by 3% 8

The European Society of Cardiology notes that gestational hypertension and preeclampsia can develop after 20 weeks gestation and present with dizziness, headache, and visual disturbances 10
The European Society of Cardiology also notes that arrhythmias, such as supraventricular tachycardias, can cause dizziness, though less common 10

The American Academy of Family Physicians warns against dismissing symptoms with "normal" hemoglobin, as iron deficiency symptoms occur before anemia develops, and standard screening misses iron deficiency without anemia 1
The Centers for Disease Control and Prevention warns against overlooking severe anemia, which requires physician referral due to significant risks including intrauterine growth restriction, prematurity, and increased peripartum blood loss 8

The American College of Obstetricians and Gynecologists notes that iron deficiency without anemia can impair fetal brain development 1
The American College of Obstetricians and Gynecologists also notes that untreated iron deficiency anemia increases the risk of fetal complications, including low birth weight, small-for-gestational-age, preterm delivery, stillbirth, and early neonatal death 1