ABSTRACT
Fetal Blood Fetal red blood corpuscles have no nuclei and are packed with fetal hemoglobin (Hb.F). The oxygen dissociation curve of this unique molecule lies to the R of that for Hb.E, but is shifted to the L of the postnatal Hb curve (Figure 3).The L shift of fetal Hb.F permits the red cells to bind avidly with O2 in the placenta, and to release it in quantity to the fetal tissues at low O2 tensions.
