Development of sucking in term infants from birth to four hours postbirth.
The development of sucking response was investigated in 30 clinically normal infants from 1 or 5 minutes postbirth until their first feeding 4 hours later. Maximum sucking pressures were measured with a research nipple attached to a portable electronic suckometer. Mean suction (negative pressure) began at 5 Torr at birth, peaked at 103 Torr at 90 minutes, and decreased thereafter to 65 Torr at 4 hours. Expression (positive pressure) began at 12 Torr, rose to 29, and decreased to 25. Mean expression pressures correlated with feeding scale scores, r = +.44(24); p less than .025, but suction pressures did not, r = +.26(24); p less than .1. Normative data were gathered on 10 additional stabilized newborns who had been fed twice successfully. Suction pressures were 96 Torr on Day 1, and 103 Torr on Day 2; expression pressures were 25 and 24 Torr, respectively. These pressures approximate those recorded in newborns between 1 and 2 hours postbirth.
D001696:Biomechanical Phenomena; D005260:Female; D006801:Humans; D007227:Infant Nutritional Physiological Phenomena; D007231:Infant, Newborn / Q000523:psychology*; D008297:Male; D009055:Mouth / Q000502:physiology*; D011312:Pressure; D013391:Sucking Behavior; D013997:Time Factors