Development and perinatal risk factors of very low-birth-weight infants. Small versus appropriate for gestational age.

371 long-term surviving very low-birth-weight (VLBW) infants born between July 1983 and June 1986 with a birthweight under 1501 g were followed-up. This sample amounted to 91% of such infants of six neonatal intensive care units in Hamburg (Germany). A neurological examination and a developmental evaluation using the Griffith Developmental Scale were carried out at the age of 18 to 20 months, corrected for gestational age. Ninety-six of the 371 infants were small for gestational age (SGA), 275 appropriate for gestational age (AGA). Striking differences between these two groups were found concerning perinatal risk factors and neurological outcome. Maternal risk factors associated with intrauterine growth retardation such as maternal toxemia and signs of fetal stress were found in a high percentage of the mothers of SGA-children, factors associated with premature labor and chorioamnionitis in mothers of AGA-children. Cerebral palsy was detected in only 7% of the SGA-children but 17.5% of the AGA-children. The difference in the development of cerebral palsy was attributed mainly to different postconceptual ages of the SGA- and AGA-children. In general, minor neurological abnormalities were detected in as many as 30% of SGA- and only 15.3% of AGA-children. None of the SGA-children over 33 weeks of gestational age developed cerebral palsy, but 25% minor neurological abnormalities. As to cerebral palsy the prognosis of SGA-infants with a very low birthweight is not different from AGA-infants with a similar gestational age. Regarding the development of minor neurological abnormalities, however, intrauterine growth retardation seems to be a risk factor independent from gestational age.