Erikson C, Allert C, Brogren Carlberg E, Katz-Salamon M. Stability of longitudinal motor development in very low birthweight infants from 5 months to 5.5 years. Acta Paediatr 2003; 92: 197-203. Stockholm. ISSN 0803-5253 Aim: The motor performance of 165 very low birthweight (VLBW) infants was assessed prospectively at 5, 10, 18 mo and 5.5 y. The aim of the study was to evaluate longitudinal stability of motor development and its association with birthweight (BW), gestational age at birth, intraventricular haemorrhage (IVH), periventricular leucomalacia (PVL) and retinopathy of prematurity (ROP). Furthermore, at 5.5 y the motor behaviour of the VLBW population was compared with that of 124 children born at term. Methods: The results of each examination were ranked into four levels and the stability of motor development was evaluated on the basis of this ranking. At 5.5 y, VLBW children and controls were compared according to percentiles in the Movement ABC. Results: Fifty-three percent of the VLBW infants displayed a stable motor development. Only PVL and BW contributed significantly to the variability in their motor performance. Forty-seven percent of the infants exhibited an unstable motor development with no association to risk factors. In the entire group only IVH and severe ROP were related to poor motor performance. The majority of the VLBW children performed within the normal range at 5.5 y but their performances were inferior to those of control children.Conclusion: VLBW infants with poor early motor performance and/or severe IVH/PVL and ROP should be recruited into individualized follow-up programmes, whereas regular ongoing monitoring by follow-up may be sufficient for those with normal early motor performance and normal ultrasound findings.