TRANSEPIDERMAL WATER-LOSS IN INFANTS BORN AT 24 AND 25 WEEKS OF GESTATION

The rate of evaporation of water from the skin of 13 infants born at 2 4 (n = 3) and 25 (n = 10) weeks of gestation was measured on the first day after birth and at postnatal ages of 1, 3, 7 and 28 d, using the gradient method. Transepidermal water loss was estimated from this rat e and corrected to an ambient relative humidity (RH) of 50%. Transepid ermal water loss, corrected to 50% RH, was high on the first day after birth (58.4 +/- 14.8 g m(-2) h(-1)) and remained at the same level du ring the second day (59.3 +/- 17.6 g m(-2) h(-1)). It then decreased s ignificantly to 43.8 +/- 9.5 at a postnatal age of 3 d, 36.1 +/- 12.6 at 7 d and 24.2 +/- 7.7 g m(-2) h(-1) at 28 d (p < 0.001). Within the group investigated, there was no significant correlation between trans epidermal water loss and body or skin temperature, birth weight, gende r, mode of delivery or gestational age. Transepidermal water loss on t he first day after birth was somewhat lower than the highest losses pr eviously found in infants born at 25 weeks of gestation, and of the sa me magnitude as previously reported for infants born at 25-27 weeks. T ransepidermal water loss at postnatal ages of 1, 3, 7 and 28 d in the present study was higher than that previously found in the group of in fants born at 25-27 weeks. In conclusion, in infants born at 24-25 com pleted weeks of gestation transepidermal water loss was high immediate ly after birth and decreased with increasing postnatal age, but at a s lower rate than previously reported for slightly more mature infants.