Background and Objectives: To ascertain the safety of repeat apheresis dona
tion, hematological and biochemical tests were performed on 511 donors with
a donation rate of over 6 times per year for a period of 12-19 months. Mat
erials and Methods: Repeat donors who had apheresis more than 6 times in th
e previous year were chosen. Data for the repeat donors at the start of the
experiments were compared with those at the end of the study. Blood sample
s were taken prior to donation. Serum protein, albumin, immunoglobulin G, A
, and M, serum ferritin levels were determined by biochemical tests. Result
s: When compared to prospective donors of 400 ml, WBC, lymphocytes, and ser
um ferritin levels were lower in a roughly frequency-dependent manner in fe
male and male donor groups at the beginning of the study. All the data for
the male group remained almost constant with increasing frequency of aphere
sis donation. However, in the female group, ferritin levels significantly d
ecreased with over 21 donations. Conclusions: The present data showed that
the serum ferritin level of the female donors decreased the most with incre
asing frequency of apheresis donation. The cumulative RBC left in the colle
cting chamber and for the laboratory test is discussed in relation to a pos
sible cause of iron deficiency in frequent apheresis donors.