Carbonyl iron Pregnancy Warnings
Carbonyl iron has not been formally assigned to a pregnancy category by the FDA. There are no controlled data in human pregnancy. Human case reports have not revealed evidence of teratogenicity. Carbonyl iron should only be given during pregnancy when the potential benefits outweigh the potential risks.
Generally, iron is considered safe for use during pregnancy and is regularly prescribed as a component of prenatal vitamin/mineral supplements. However, controversy exists as to whether or not routine iron supplementation is needed in the non-anemic pregnant patient. Although the FDA has not assigned iron to a pregnancy category, the European Community Committee on Proprietary Medicinal Products has rated iron preparations a category “A”, defined as a medicinal product assessed in pregnant women with no known harmful effects with respect to the course of pregnancy and the health of the unborn and the neonate. Anemia may be a risk factor for preterm delivery and low birth weight and should be diagnosed and treated as soon as possible, either before pregnancy or in the first trimester. Because supplementation with iron may reduce the dietary absorption of zinc, it may be important to assess zinc status as well. Most prenatal vitamins also contain adequate amounts of zinc. Absorption of iron and zinc may be reduced if calcium is also a component of the prenatal multivitamin.
Carbonyl iron Breastfeeding Warnings
One study demonstrated that a moderate iron supplementation of non-anemic nursing mothers (40 mg elemental iron daily over 3 months starting 2 days after delivery) resulted in increased maternal iron reserves, no significant alterations in milk iron concentration or lactoferrin, and no harmful effect on the infant. Another study evaluated oral iron supplementation in 19 anemic women receiving 100 mg elemental iron per day starting 2 days after delivery and continuing for 30 days. Ten non-anemic women had received iron supplementation during pregnancy. Iron and lactoferrin concentrations in milk obtained at 2 and 30 days after delivery did not differ between groups at either stage of lactation.
Several reports suggest that iron supplementation during lactation does not significantly affect the total concentration of iron in human milk. Carbonyl iron administration during lactation is generally considered safe for the infant by most clinicians.