[Growth curves for premature infants during the 1st year of life].

A 107 newborn premature children were anthropometrically evaluated during the first 12 months of their lives at the Growth Clinic of the National Institute of Perinatology in Mexico City. The study was longitudinal and included variables such as weight, height, cephalic, thoracic, abdominal and bronchial perimeters. The data are show in percentiles of 10, 50 and 90 for each variable. A symmetrical logarithmic behavior throughout the entire curve was seen with each of the six indicators evaluated, whose greatest percentage increase within the growth rate was generally seen during the first semester, decreasing during the second. It was seen that once the child reaches one, the premature infant reaches the full-term child (50 percentile) in weight, height and cephalic perimeter. In addition, the average speed of growth was four times greater for weight, two times greater for height and similar for the cephalic perimeter of the premature child with respect to the full-term infant. We conclude that it is useful to count on specific growth curves for premature children since their speed and rhythm of growth are different than for the full-term child during the first year of life.