Optimizing diagnosis and treatment of iron deficiency and iron deficiency anemia in women and girls of reproductive age: Clinical opinion.

Iron deficiency (ID) is the world's most common disorder and one of the top five causes of years lived with disability. Whereas low serum ferritin is diagnostic of ID, ferritin-an acute phase reactant-may be elevated in inflammatory states and the first trimester of pregnancy even if ID exists. Consequently, in early pregnancy or chronic inflammation, percent transferrin saturation (TSAT) measurement is the best indicator of iron status. Unfortunately, current guidelines do not recommend routine screening for ID in either pregnant or nonpregnant women in the absence of anemia. This circumstance should be urgently reviewed based on available data. While oral formulations have long been the standard for iron replacement therapy and are widely available and inexpensive, oral iron is frequently associated with adverse gastrointestinal effects for the majority-a major reason for poor adherence, inadequate repletion, and persisting ID symptoms and sequellae. Although safe intravenous iron administration was introduced in the mid-1950s, formulations with cores binding the elemental iron more tightly became available in the 2000s, allowing complete and safe replacement, even in a single setting. Prospectively acquired neonatology evidence reports oral iron's failure to reach the developing fetus when the mother is iron deficient. Consequently, while oral iron remains frontline in the first trimester because of insufficient safety data for intravenous iron, the author recommends that the intravenous route should be the gold standard for second-trimester ID when hemoglobin concentrations are less than 10.5 g/dL and for all iron-deficient women in their third trimester.