Hematocrit shows what portion of your blood is red blood cells, helping assess oxygen-carrying capacity and hydration.
Hematocrit is the share of your blood made up of red blood cells, given as a fraction or percentage. If your hematocrit is 0.45, then 45 percent of your blood volume is red cells and the rest is mostly plasma.
It is a quick measure of how concentrated your red cells are and moves closely with hemoglobin, so the two are usually read together.
A hematocrit test helps detect anaemia, when the value is low, or thickened, concentrated blood, when it is high. Low hematocrit often reflects iron deficiency, blood loss, or chronic illness.
High hematocrit can come from dehydration, smoking, living at altitude, or, rarely, a bone marrow disorder. Because hydration affects it, hematocrit is most reliable when read alongside hemoglobin and the rest of the blood count.
Aniva reads your result against research-backed ranges, not just the lab's wide normal. The reference shown below is specific to this biomarker.
Ranges are guidance, are sex-specific, and vary by laboratory.
| Group | Reference range (SI) |
|---|---|
| Women | 0.36 to 0.46 (36 to 46 percent) |
| Men | 0.40 to 0.50 (40 to 50 percent) |
Aligned to German laboratory practice (DGKL). Always interpret against your own lab's range.
Dehydration raises hematocrit and overhydration lowers it. Pregnancy lowers it. A sample taken just after heavy bleeding may look near normal until fluid balance settles. Very high white cell counts can affect some methods.
Read together with hemoglobin, red blood cell count, and red cell indices such as MCV.
What does my hematocrit result mean? It shows what share of your blood is red cells. Higher or lower levels can reflect hydration, altitude, or red cell changes.
Do I need to fast for this test? No. Eat and drink normally unless your clinician orders other fasting labs.
What can affect the result day to day? Hydration, recent illness, smoking, altitude, pregnancy, and some medicines can shift values. Heavy exercise just before the draw can, too.
How often should I check hematocrit? It’s usually checked with a routine CBC or when symptoms appear. Follow your clinician’s advice for repeat testing.
How long do results take? Results are usually ready in about 7 days.
What should I discuss with my clinician? Share symptoms, recent blood loss or donation, your medicines and supplements, and any altitude or travel changes.
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