What does a low hematocrit indicate?

Causes of decreased hematocrit include physiological and pathological factors. Physiological causes commonly occur during the second and third trimesters of pregnancy, and hematocrit may also decline in elderly individuals. Pathological causes are frequently associated with: 1. Gastrointestinal disorders—e.g., peptic ulcer disease, hemorrhoids, and cirrhosis; 2. Hematologic disorders—e.g., iron-deficiency anemia and megaloblastic anemia; 3. Immune-mediated disorders—e.g., systemic lupus erythematosus and Sjögren’s syndrome; 4. Endocrine and metabolic disorders—e.g., primary aldosteronism and severe heart failure.