Infancy is the period of most rapid extrauterine growth and physiologic changes.
There is apt to be a physiologic anemia at 2-3 month and an iron deficiency anemia at 6-18 month possibly due to an inadequate weaning diet.
Korea has improved her social and economic status during the last few decades and mothers are more concerning about weaning diet and infant care.
The author checked hemoglobin, hematocrit and RBC counts on 803 cases (male 435, female 368) or healthy Korean newborns and infants up to 30 months of birth. Mean corpuscular volume, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration were calculated as usual, according to Wintrobe.
1. The highest hemoglobin level was 19.2 Gm/100ml at 5 days after birth, and the lowest level 10.8 Gm/100ml at 1-3 month. Thereafter the values were 111.4-11.9 Gm/100ml up to 2 years.
2. The average value of the hematocrit was 62% at 5 days after birth and 33% at 1-3 month. Thereafter it averaged 36-37% up to 2 years.
3. The average RBC count was 5,660,000/cub.mm at 5 days after birth, which was the highest level, and the lowest level 3,760,000/cub.mm was at 1-2 month. Thereafter the average RBC count was s4,350,000-4,840,000/cub.mm up to 2 years.
4. The average M.C.V. value, 113 cub. micron at birth, gradually decreased till about 1 year(13-15 month), when the value averaged 76 cub. micron. Thereafter it increased gradually.
5. The average M.C.H. value was highest at birth(37rr) and then, decreased gradually. At 1 year (10-11 month) the value was lowest, being 24rr. Thereafter it increased gradually.
6. The average M.C.H.C. value was 31-33% regardless the age groups.
7. No sex difference was noticed in all age groups.