[Measurement of serum ferritin in blood donors with reference to donation intervals].

Serum ferritin shows a high correlation to the storage iron in the reticuloendothelial cells of the bone marrow. Therefore it is a reliable test to watch over the body iron stores of blood donors. Measurements were made on 284 donors (171 male, 113 female) with a donation interval of 12 weeks without iron therapy and on 59 subjects (20 male, 39 female) with a donation interval of 6 weeks receiving 100 mg Fe2+/day. In the immunoradiometric determination of serum ferritin all groups showed a steady decrease of the values to a subnormal but not yet anemic level. Women could bear the short-donation intervals with oral iron supplementation better than the longer intervals without the iron therapy. Men did not show any significant differences in the ferritin values. In times of increased demand for blood or before planned autologous transfusions, the donation intervals can be shortened, if an oral iron supplementation is guaranteed. Female donors should get iron at each phlebotomy.