We present a longitudinal study on the neurodevelopmental outcome in preterm infants with extremely low birth weight <1000 g (ELBW) to answer the question at which age a developmental prognosis can be given.Methods
A group of 129 ELBW, median birth weight: 794 g (SD 123 g), gestational age: 27.0 weeks (SD 2.0 weeks), born between 1993 and1998, were followed up to the age between 6 and 10 years (mean 8.5 years [SD 1.7 years]) and evaluated by neurodevelopmental and psychometric tests. The status of children without cerebral palsy was ranked into categories of major, minor and no developmental impairments.Results
At the time of the last follow-up examination 17% of the children showed a major impairment including 9% cerebral palsy, 42% a minor impairment and 41% were normally developed. The longitudinal analysis of cases without cerebral palsy reveals that an assessment ‘at term’ can only give the correct developmental prognosis in 49% of the cases. At the corrected age of 12 months the prognosis is correct in 59% of the cases, whereas at the corrected age of 3 years 70% proves to be right. Diagnosis of cerebral palsy could be confirmed at the corrected age of 2 years with sufficient reliability.Conclusion
The neurodevelopmental evaluation of former preterm infants with a birth weight <1000 g demands a follow-up period of at least 6 years in order to make reliable statements. We are doubtful that follow-up testing completed prior to this age can yield reliable results.