How low your hemoglobin hematocrit to do work up for anemia?

Find cause. I would investigate any anemia in the hope of finding a treatable cause, especially before things get serious. Iron deficiency causes fatigue before it causes anemia.
In a young female. I would say under HGB 10.5 or hct 30, unless there are other issues of concern.
Below normal. Anemia is a hemoglobin (HGB) or hematocrit (hct) below "normal". Normal is defined by the laboratory doing the testing and varies by laboratory and "normal" population that the lab calibrates based on. Usually <12 g/dl HGB fora woman is anemia.

Related Questions

How quickly will anemia from low iron damage the heart? Hemoglobin is 9.7, hematocrit 31.3. Normal 11mos ago, but is it too late? 35 yrs old.

You will be fine. You just need to supplement back the iron. This hemoglobin level is low, but I expect you to recover fully. Once you take the iron supplements, check back with your doctor for repeat labs to confirm your good health. Then you will see. You have your young age and relative good health that will help you pull through this time. Read more...