The first year of human life: coordinating respiration and nutritive swallowing.

This study provides the first documented report of the maturation of breathing-swallowing coordination during feeding in ten healthy term human infants through the first year of life. A total of 15,073 swallows were obtained across ten assessments between 48 h and 12 months of age. Midexpiratory swallows represented the dominant pattern of breathing-swallowing coordination within the first 48 h (mean = 45.4%), but the prevalence of this pattern declined rapidly in the first week to 29.1% (p = 0.012). Inspiratory-expiratory swallows increased with age (p < 0.001), particularly between 9 (37.0%) and 12 months (50.4%). Between 72.6% and 75.0% of swallows were followed by expiration in the latter 6 months, which is an adult-like characteristic. These data suggest that while postswallow expiration is a robust feature of breathing-swallowing coordination from birth, two major shifts in the precise patterns occur: the first after 1 week of postnatal feeding experience and the second between 6 and 12 months, most likely due to neural and anatomical maturation.