Early Anemia in Mammals

Most data indicate that the basic hypoxia-erythropoietin mechanism operates in fetal life and also postnatally. This means that erythropoietin increases following hypoxia irrespective of the production site of the hormone and decreases when there is a surplus of oxygen-carrying capacity. There are, however, several studies indicating that regulation of erythropoiesis in the neonatal mammal differs from that in the adult [1, 2]. Erythropoiesis in the perinatal period is not a steady-state condition, it is constantly changing. This must be taken into consideration both regarding the experimental design and the conclusions that can be drawn from the studies.