Scar formation after skin injury to the human foetus in utero or the premature neonate

A macroscopically visible scar was present at birth in three infants with a history of injury during amniocentesis at 16-20 weeks' gestation. In sever al neonates born between 21 and 31 weeks' gestation, chemical injury to the skin caused by extravasation of calcium gluconate healed by formation of a large scar. In the infant born at 21 weeks, biopsy of the injured area sho wed infiltration by large numbers of neutrophils and macrophages. It appear s that a very immature neonate can mount a prominent inflammatory reaction and that both a midtrimester foetus and a very immature neonate heal injuri es to the skin by scar formation and not by scarless healing.