Abstract: Diaper rash is a common infant malady. This study documents the earliest stages of rash in a cohort of 31 healthy term newborns over the first 28 days of life. The diaper area was evaluated using a standardized diaper rash grading scale. The anal, buttock, genital, intertriginous, waistband, and leg areas were assessed separately. At birth the average grade was 0.1 and none of the infants had specific features of advanced rash. Nineteen percent had dryness and/or slight redness. By day 7, 71% of infants had some features of skin compromise, giving rise to an overall grade of 0.6. Both the frequency and overall grade increased during postnatal weeks 2 and 3. Overall scores for days 21 and 28 were the same (1.1). The perianal area had the highest overall regional rash grade. Gender differences were present for the genital area only. These findings indicate that epidermal barrier breakdown is an uncommon finding at birth. Clinical signs of irritated skin in the diaper area develop progressively over the first postnatal month. A better understanding of the mechanisms conferring epidermal barrier protection at birth may be important for developing skin care products and practices to extend this protection later into life.