Effects of gestation and birth weight on the growth and development of very low birthweight small for gestational age infants: a matched group comparison

Aims-To investigate the effects of small for gestational age (SGA) in very low birthweight (VLBW) infants on growth and development until the fifth ye ar of life. Methods-VLBW (< 1500 g) infants, selected from a prospective study, were cl assified as SGA (n = 115) on the basis of birth weight below the 10th perce ntile for gestational age and were compared with two groups of appropriate for gestational age (AGA) infants matched according to birth weight (AGA-BW ; n = 115) or gestation at birth (AGA-GA; n = 115). Prenatal, perinatal, an d postnatal risk factors were recorded, and duration and intensity of treat ment were computed from daily assessments. Body weight, length, and head ci rcumference were measured at birth, five and 20 months (corrected for prema turity), and at 56 months. General development was assessed at five and 20 months with the Griffiths scale of babies abilities, and cognitive developm ent at 56 months with the Columbia mental maturity scales, a vocabulary (AW ST) and language comprehension test (LSVTA). Results-Significant group differences were found in complications (pregnanc y, birth, and neonatal), parity, and multiple birth rate. The AGA-GA group showed most satisfactory growth up to 56 months, with both the AGA-BW and S GA groups lagging behind. The AGA-GA group also scored significantly more h ighly on all developmental and cognitive tests than the other groups. Devel opmental test results were similar for the SGA and AGA-SW groups at five an d 20 months, but AGA-BW infants (lowest gestation) had lower scores on perf ormance intelligence quotient and language comprehension at 56 months than the SGA group. When prenatal and neonatal complications, parity, and multip le birth were accounted for, group differences in growth remained, but diff erences in cognitive outcome disappeared after five months. Conclusions-Being underweight and with a short gestation (SGA and VLBW) lea ds to poor weight gain and head growth in infancy but does not result in po orer growth than in infants of the same birth weight but shorter gestation (AGA-BW) in the long term. SGA is related to early developmental delay and later language problems; however, neonatal complications may have a larger detrimental effect on long term cognitive development of VLBW infants than whether they are born SGA or AGA.