Fetal Hemoglobin (HBF)

Fetal hemoglobin is the main oxygen transport protein in the fetus during the last seven months of development in the uterus and in the newborn until roughly 6 months old. Functionally, fetal hemoglobin differs most from adult hemoglobin in that it is able to bind oxygen with greater affinity than the adult form, giving the developing fetus better access to oxygen from the mother's bloodstream. In newborns, fetal hemoglobin is nearly completely replaced by adult hemoglobin by approximately the twelfth week of postnatal life. In adults, fetal hemoglobin production can be reactivated pharmacologically, which is useful in the treatment of such diseases as sickle-cell disease.After the first 10 to 12 weeks of development, the fetus' primary form of hemoglobin switches from embryonic hemoglobin to fetal hemoglobin. At birth, fetal hemoglobin comprises 50-95% of the child's hemoglobin.