This patient should discontinue her oral iron supplementation, because she does not have iron deficiency. She likely has α-thalassemia trait presenting with a mild microcytic anemia. Microcytic hypochromic erythrocytes and target forms may be seen on the peripheral blood smear in α- and β-thalassemia, which can only be differentiated by hemoglobin electrophoresis, in which α-thalassemia shows a normal pattern and β-thalassemia typically has a slightly increased hemoglobin A₂ band. α-Thalassemia trait (or α-thalassemia minor, double gene deletion -α/-α or –/αα) is associated with mild anemia, microcytosis, hypochromia, target cells on the peripheral blood smear, and, in adults, normal hemoglobin electrophoresis results. The (-α/-α) variant is often mistaken for iron deficiency. Microcytic anemia associated with a normal or slightly increased erythrocyte count is characteristic of thalassemia but not of iron deficiency. The red cell distribution width (RDW) is also useful in distinguishing between thalassemia and iron deficiency, because the RDW is often elevated in iron deficiency but normal in thalassemia. No treatment or monitoring is necessary for α-thalassemia trait.

The mild anemia of α-thalassemia is often confused with iron deficiency anemia, especially in a patient who could have a plausible cause for iron deficiency from menstrual blood loss. However, this patient's iron values are not consistent with iron deficiency, and the normal RDW argues against iron deficiency and the need for iron replacement therapy. This also rules out the need for evaluation for gastrointestinal blood loss with fecal occult blood testing.

Starting an oral contraceptive pill could potentially lessen the patient's menstrual bleeding, but because she is not iron deficient, oral contraceptives would not correct her mild anemia.