Passage of the first stool in very low birth weight infants.

Times of first stool passage were studied in 171 infants who weighed less than 1,500 g at birth. Delayed passage (greater than 48 hours) was noted in 20.4% of this group. Significant differences were noted between the delayed and nondelayed groups for gestational age, presence of severe respiratory distress syndrome, and the time of the first enteral feeding. In very low birth weight infants, delay in the passage of the first stool is a common occurrence. This delay is probably due to physiologic immaturity of the motor mechanisms of the gut, lack of triggering effect of enteral feeds on gut hormones, and the presence of severe respiratory distress syndrome, which may singly or in concert adversely affect gastrointestinal motility.