Growth in weight, recumbent length, and head circumference for preterm low-birthweight infants during the first three years of life using gestation-adjusted ages.

Data from 867 preterm low-birthweight participants in the Infant Health and Development Program (IHDP) were used to develop reference data for growth status at an age and for increments from term to 36 month gestation-adjusted age (GAA). Weight, length and head circumference were recorded at 4 month intervals in the first year and at 6 month intervals in the second and third years. Selected percentiles for values at an age (status values) and increments for age intervals are presented in graphs separately for VLBW infants (< or = 1500 g at birth) and for LBW infants (1501-2500 g at birth). Percentiles of weight increments are presented beginning shortly before term for 1 month intervals to 6 month GAA, for 2 month intervals to 12 month GAA, and for 3-month intervals to 36 month GAA. Percentiles for length and head circumference increments are presented from term to 6 months for 2-month intervals, and to 36 month GAA for 3 month intervals. Among LBW infants, boys, had larger status and increment values than girls (P < 0.05), but there were no significant sex-associated differences in VLBW infants for status or increments. The mean status values and increments in weight and head circumference of the LBW infants were larger than those of VLBW infants, but the differences in length were not significant.