The dermis.

All the dermal structures are less well developed in the newborn than in the older infant or child, but there are few important consequences of this. Sweating in response to a thermal stimulus occurs at birth in the term infant and can be detected in most preterm infants from 2 weeks of age. It is poorly developed though. Emotional (palmar/plantar) sweating is present from birth in term infants only. Skin blood flow can be regulated in term and preterm infants, and is often measured indirectly as a temperature gradient. Such a gradient is temperature as well as illness dependent which limits its use as a clinical tool. Sensory nerve endings are readily stimulated in the most immature infants. Finally, damage to the skin in the newborn period commonly leads to scarring, although this usually improves with time. Copyright 2000 Harcourt Publishers Ltd.