Iron Deficiency Assessment in Post-Breastfeeding Women

Core Iron Assessment Panel

The Centers for Disease Control and Prevention recommends serum ferritin as the single most important test and the earliest indicator of depleted iron stores, with a level of <15 μg/L having 99% specificity for absolute iron deficiency 1, 2, 3, 4
Ferritin levels <30 μg/L generally indicate low body iron stores requiring intervention, with normal reference being 43 μg/L for women 3, 4
Transferrin saturation (TSAT) calculated from serum iron and total iron-binding capacity is essential, with TSAT <20% indicating insufficient iron available for red blood cell production 3, 4
A complete blood count (CBC) with red cell indices is necessary, as hemoglobin and hematocrit detect late-stage iron deficiency (anemia) 1, 2, 5

Ferritin rises during inflammation, infection, or tissue damage independent of iron status, and a "normal" ferritin in the presence of inflammation may mask true iron deficiency 1, 2, 3, 4
No single test definitively diagnoses iron deficiency, and biochemical tests (ferritin, TSAT) detect earlier changes than hematological tests (hemoglobin, hematocrit) 1, 2, 5

The American College of Obstetricians and Gynecologists recommends ordering a comprehensive panel including serum ferritin, serum iron and total iron-binding capacity, complete blood count with differential, and vitamin B12 and 25-hydroxyvitamin D levels for post-breastfeeding women with symptoms of iron deficiency 1, 2, 3, 4