What test should be ordered for a young female with a history of bleeding and initial lab results indicating microcytic anemia?

In the scenario described, where a young female presents with a history of bleeding and initial lab results indicating microcytic anemia, the most appropriate test to order is related to the evaluation of bleeding disorders.

The presence of microcytic anemia often suggests iron deficiency, a common cause in young females due to menstruation or other bleeding but does not fully address the bleeding history. Therefore, it’s essential to assess the hemostatic function to identify any underlying bleeding disorders that could be contributing to both the anemia and the bleeding history.

Bleeding time and platelet aggregometry specifically evaluate the primary hemostatic pathway, which involves platelets and their response to vascular injury. Perform these tests in cases where there is unexplained bleeding, particularly when considering platelet function disorders or von Willebrand disease, which can manifest with both anemia and bleeding symptoms.

In summary, ordering bleeding time and platelet aggregometry is the appropriate choice in this context, as it allows for an assessment of the patient's bleeding tendency, which is critical given the history of bleeding along with laboratory findings of microcytic anemia.