Iron Requirements

Increase in the maternal blood supply increases the demand for dietary iron. Iron requirements increase substantially during pregnancy (an additional 700–800 mg throughout the pregnancy), although a higher rate of absorption also compensates for this increase. Athletes also have higher iron requirements and potentially higher losses than nonathletes. Pregnant or lactating athletes have very high iron requirements, despite no menstrual blood loss, and are unlikely to meet these needs from their dietary intake.

Iron supplementation may be necessary to meet the physiological needs of pregnancy and exercise. If the athlete continues training through pregnancy, hemoglobin and hematocrit should be measured every 6 to 8 weeks and 2 to 3 weeks postpartum. A level of hemoglobin less than 12gdL has been suggested to impede training in the pregnant athlete. Iron deficiency anemia is commonly treated with 60–120 mg of ferrous iron throughout the day. Once hemoglobin levels return to normal, 30 mgd may be continued. Excessive doses of iron are not recommended in pregnancy as they have been linked to the pathogenesis of preeclampsia and gestational diabetes. For women of childbearing age who become pregnant, the importance of eating foods high in heme-iron or iron-rich foods or iron-fortified foods with an enhancer of iron absorption such as vitamin C-rich foods is highlighted as one of the key recommendations of the 2005 Dietary Guidelines for Americans.