Answer:
During early gestation, fetal skin wounds will heal without scarring. The exact reasons for this are not known. Studies have shown that the fetal fibroblast has different properties including greater migratory ability and greater ability to induce dermal appendage formation. The immune response in fetal wounds has a greater proportion of monocytic infiltration and less neutrophilic response which corresponds with the lack of acute inflammation seen in fetal wounds. The cytokine profile in the fetal wound is also different, particularly in decreased expression of TGF-beta and FGF. Epithelialization occurs more rapidly in fetal wounds, but angiogenesis is also absent. The fetal wound matrix shows greater amounts of hyaluronic acid and a greater efficiency in matrix reorganization during healing. The ability of fetal skin to heal scarlessly diminishes as gestation progresses and corresponds to changes in these elements which more closely approximate their adult counterparts.