Why does an embryo produce a different type of hemoglobin from an infant child or adult blood?

An embryo produces a different type of hemoglobin, known as fetal hemoglobin (HbF), which has a higher affinity for oxygen than adult hemoglobin (HbA). This adaptation allows the fetus to efficiently extract oxygen from maternal blood in the low-oxygen environment of the womb. As development progresses and the infant is born, the need for this high-affinity hemoglobin decreases, leading to a transition to adult hemoglobin, which is better suited for breathing air and meeting the oxygen demands of a growing child and adult.