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Compared to routine supplementation in pregnancy, higher doses of iron are required for the treatment of maternal anemia (up to 200 mg/day). Oral iron therapy is most often utilized, with a list of the most commonly available formulations given in Table 11.2. Enteric‐coated forms should be avoided because they are poorly absorbed; absorption is increased by intake of iron on an empty stomach and with vitamin C or orange juice. Although several trials have been conducted to compare iron formulations, it is not possible to assess the efficacy of the treatments due to the use of different drugs, doses, and routes. Gut absorption decreases with increasing doses of iron; therefore it is best to divide the total daily dose into 2–3 doses.

Table 11.2 Oral preparations for therapy of iron deficiency anemia

Source: Based on ACOG Practice Bulletin No. 107, 2009.

Type of iron	Elemental iron (mg)	Brand
Ferrous fumarate	64–200	Femiron, Feostat, Ferrets, Fumasorb, Hemocyte, Ircon, Nephro‐Fer, Vitron‐C
Ferrous sulfate	40–65	Chem‐Sol, Fe50, Feosol, Fergensol, Ferinsol, Ferogradumet, Ferosul, Ferratab, FerraTD, Ferrobob, Ferrospace, Ferrotime, Moliron, Slowfe, Yieronia
Ferrous gluconate	38	Fergon, Ferralet, Simron
Ferric	50–150	Ferrimin, Fe‐Tinic, Hytinic, Niferex, Nu‐iron

A relationship exists between dose of oral iron and gastrointestinal side effects, with worsening of symptoms as dose increases, with such side effects leading to discontinuation of therapy in 50% of women. To encourage compliance, it is important to minimize side effects by increasing the dose gradually, with larger doses in the evening, and consideration for the use of an iron sulfate elixir which allows more gradual titration of dose. Stool softeners are often required to prevent constipation. Serum reticulocyte count should be elevated within 7–10 days of treatment initiation, with an improvement in hemoglobin levels less rapid – the hemoglobin deficit should be expected to halve in one month and normalize by 6–8 weeks after initiation of treatment. To replenish iron stores, oral therapy should be continued for three months after the anemia has been corrected.

Intravenous (IV) iron therapy is generally reserved for women who cannot or will not take oral iron preparations. Hemoglobin indices are equivalent after 40 days of treatment in women receiving IV iron therapy compared to those receiving oral therapy, but the rate of rise is more rapid in women receiving IV therapy. Randomized trials have not shown significant differences in need for maternal blood transfusion, neonatal birthweight, or neonatal anemia between the two forms of supplementation, and studies have demonstrated a preference for oral supplementation among most women. Therefore, IV therapy is indicated only in patients with severe anemia with intolerance to oral therapy or malabsorption. Iron dextran is associated with a greater risk of anaphylaxis and is not recommended in the light of other available formulations with a lower risk of allergic reaction. Intravenous preparations tested in pregnancy or puerperium are shown in Table 11.3.

Table 11.3 Intravenous preparations for therapy of iron deficiency anemia

Source: Based on ACOG Practice Bulletin No. 107, 2009.

Type of intravenous iron	Commercial names	Dose
Iron dextran LMW	INFeD, Cosmofer	1000 mg/60 min (diluted in 250–1000 mL of normal saline)
Ferric gluconate	Ferlecit	125 mg/30 min (diluted in 100 mL of normal saline)
Iron sucrose	Venofer	200 mg/60 min
Ferric carboxymaltose	Ferinject	100 mg/15 min

Erythropoietin is not indicated in the treatment of iron deficiency anemia unless the anemia is caused by chronic renal failure or other serious chronic medical conditions and is expensive with many associated side effects – its use should be reserved for treatment by a hematologist.

Blood transfusion is indicated only for anemia associated with hypovolemia from blood loss or in preparation for a cesarean delivery in the presence of severe anemia.