Hematocrit is the percentage of blood volume occupied by red blood cells. Abnormal values reflect anemia or polycythemia and can indicate dehydration, bleeding, chronic disease, smoking, high-altitude adaptation. Underwriting considers hematocrit alongside hemoglobin, MCV, iron studies,and clinical notes. Significant or unexplained abnormalities may trigger ratings or postponement until stabilized.

When hematocrit is abnormal, advisors gather repeat labs and physician notes to show stability or resolution. Addressing dehydration, iron deficiency, or sleep apnea can improve outcomes.