Low hematocrit means a reduced proportion of red blood cells in your blood, commonly indicating anemia. Causes include blood loss, iron, B12 or folate deficiency, chronic disease, bone marrow problems, pregnancy, or overhydration. Symptoms are fatigue, weakness, shortness of breath and pale skin. A doctor may order tests (CBC, iron studies, B12) and recommend supplements, treating underlying conditions, or rarely transfusion.

Hematocrit (Hct) is the percentage of blood volume made up by red blood cells, usually reported in a complete blood count or as packed cell volume. Normal ranges are roughly 41–53% for adult men and 36–46% for adult women. Low Hct suggests anemia or blood loss; high Hct indicates dehydration or conditions causing excessive red cell production. It helps assess oxygen‑carrying capacity.

Hematocrit is the percentage of blood made up by red blood cells. In pregnancy plasma volume expands more than red cell mass, causing physiologic hemodilution and a lower hematocrit. Typical pregnancy values are lower than in nonpregnant women (commonly about 30–36%). Values below roughly 33% are often used to define anemia in pregnancy and merit evaluation and treatment as needed.

A hematocrit of 25% means red blood cells make up 25% of blood volume — markedly below typical adult ranges. It indicates significant anemia and can cause fatigue, weakness, shortness of breath, pallor and rapid heartbeat. Common causes include blood loss, iron, B12 or folate deficiency, chronic disease or bone marrow disorders. Evaluation and treatment depend on the cause and may require supplements, transfusion or further testing.

Low hematocrit commonly results from anemia (iron‑deficiency, B12/folate deficiency, hemolytic anemia), chronic kidney disease (reduced erythropoietin), bone marrow disorders (aplastic anemia, myelodysplastic syndromes, leukemia), chronic inflammatory or infectious diseases (anemia of chronic disease), acute or chronic blood loss, liver disease, hypersplenism, and certain cancers. Endocrine disorders like hypothyroidism can also contribute.

Treating low hematocrit depends on the cause: address bleeding and underlying disease, replace blood for severe symptomatic cases, and correct nutritional deficiencies with iron, vitamin B12 or folate and diet changes. In chronic kidney disease or cancer, erythropoiesis-stimulating agents may be used. Monitor levels and follow up with your clinician to adjust therapy and investigate persistent or recurrent anemia.