[Growth of small for gestational age preterm infants].

OBJECTIVE To describe the linear growth and growth velocity of preterm infants born small for gestational age according to variables such as weight, length and head circumference, from birth to three months of corrected age. METHODS Prospective study of one hundred preterm infants born small for gestational age from 28 to 36 weeks after birth and classified as small according to the weight for their gestational age. The anthropometric data was obtained at birth, and continued to be measured weekly until the probable delivery date and monthly until three months of corrected age. Growth curves were calculated according to the mean values adjusted by the polynomial function of Count model. RESULTS The infants' growth curves for the three variables were much below the ones of the preterm infants with adequate size for gestational age until the fortieth week. However, the head circumference growth reached the 10th percentile curve of the NCHS at the fortieth week, and the 25th percentile at three months of corrected age. The weight growth curve reached the 10th percentile curve around one month and a half for males and two months and a half for females. The length growth curve reached the 10th percentile for males at three months of corrected age and it almost reached that percentile for females after the same period of time. CONCLUSIONS A tendency of recovering weight and length related to preterm infants with adequate size and term newborns was observed. The head circumference showed an obvious and early recovery.