Hemoglobin F (HbF) is a type of hemoglobin found primarily in fetuses and newborns. It consists of two alpha and two gamma chains, which allow it to bind oxygen more effectively than the adult form, Hemoglobin A. This increased affinity for oxygen is crucial for fetal development, as it helps transport oxygen from the mother’s bloodstream. As a person grows, the production of Hemoglobin F decreases, typically being replaced by Hemoglobin A by around six months of age. In some conditions, such as sickle cell disease or beta-thalassemia, elevated levels of Hemoglobin F can persist into adulthood, providing some protective benefits against symptoms.