What is the recommended treatment for moderate iron deficiency anemia in pregnancy?

Treatment of Moderate Iron Deficiency Anemia in Pregnancy

Treat moderate iron deficiency anemia in pregnancy with 60-120 mg of elemental iron daily via oral supplementation, which is the first-line therapy recommended by major guidelines. 1

Initial Treatment Approach

Start oral iron therapy immediately upon diagnosis without waiting for additional confirmatory testing in pregnant women who are not acutely ill. 1 The standard treatment regimen includes:

• Elemental iron dose: 60-120 mg daily taken orally 2, 1
• Treatment should continue throughout pregnancy and the postpartum period to prevent recurrence 1
• Monitor response with repeat hemoglobin/hematocrit testing after 4 weeks of treatment 1

Optimizing Oral Iron Therapy

To maximize absorption and minimize side effects:

• Counsel patients about iron-rich foods and dietary factors that enhance iron absorption (such as vitamin C) 1
• Avoid concurrent calcium supplements and antacids, which decrease iron absorption; take these at different times of day 3
• Consider taking iron at bedtime to reduce gastrointestinal side effects 3
• Recent evidence suggests intermittent dosing may be as effective as daily dosing with fewer side effects 4

Common side effects include gastrointestinal symptoms, darkening of urine or stool, and staining of teeth and gums. 2 There is a trend between higher doses and increased adverse effects. 5

Special Population Considerations

Vegetarian women require particular attention as their iron requirements may be almost twice as high due to lower absorption of non-heme iron from plant sources; consider higher supplementation doses in this population. 1, 3

Higher-risk groups include:

• Non-Hispanic Black and Mexican American women (higher prevalence rates) 3
• Women with short intervals between pregnancies 3
• Women with gastrointestinal disease or medications that decrease iron absorption 2

When to Consider Intravenous Iron

Before switching to IV iron, you must confirm compliance with oral iron and rule out other causes of anemia unresponsive to iron therapy (such as thalassemia minor or sickle cell trait). 1, 6

Treatment failure is defined as no response to oral iron after 4 weeks despite compliance with the regimen. 6

If IV iron is indicated during pregnancy:

• Ferric carboxymaltose is the preferred IV formulation due to rapid effectiveness and better tolerability 6
• Dosing for patients ≥50 kg: 750 mg IV in two doses separated by at least 7 days (total 1,500 mg per course) 7
• Dosing for patients <50 kg: 15 mg/kg body weight IV in two doses separated by at least 7 days 7
• IV iron administration should be performed in settings with resuscitation facilities available due to rare but serious allergic reactions 6

Treatment Duration and Goals

Continue iron supplementation until hemoglobin values normalize (>10.5 g/dL) and ferritin reaches 300-360 mcg/dL, then maintain these levels for at least one year. 8 Treatment should extend throughout pregnancy and into the postpartum period. 1

Postpartum Monitoring

Monitor hemoglobin levels at 4-6 weeks postpartum in women at risk for persistent anemia to ensure adequate iron repletion. 1

Critical Pitfall to Avoid

The most common error is failing to identify women at higher risk who need increased supplementation (such as vegetarians, minority populations, or those with short interpregnancy intervals) and treating them with standard prenatal vitamin doses (30-48 mg) rather than therapeutic doses (60-120 mg). 3