RESUMEN
BACKGROUND: In preterm infants, skin barrier maturation entails regional variability. OBJECTIVES: To characterize postnatal skin barrier development in covered, uncovered and diapered regions in healthy premature infants over a longitudinal observation period. METHODS: Transepidermal water loss (TEWL), stratum corneum hydration (SCH), pH and sebum were measured at postnatal ages of 1-7 days and 2-7 weeks on the forehead, abdomen, thigh and buttock of preterm infants (gestational age 30-37 weeks; n = 48) under monitored ambient conditions. A standard minimal skin care regimen was practised. RESULTS: TEWL increased significantly on the buttock (p = 0.007), while remaining stable on the forehead, abdomen and thigh. SCH and sebum remained stable in all studied body regions with increasing age. On the buttock, pH increased (p = 0.049), while other body regions exhibited a significant decrease (p ≤ 0.019). TEWL (p < 0.001) and SCH (p ≤ 0.002) revealed significantly higher values on the buttock, compared to other body regions. CONCLUSIONS: Stable TEWL, SCH and sebum values may indicate a lack of skin barrier maturation. Postnatal decrease in skin pH suggests an adaptation process with acid mantle formation. Differences in skin barrier development were observed between anatomical regions. SCH, TEWL and pH values demonstrated a distinct course in the diaper area, indicating an impaired skin barrier function in this region.