Impact of improved survival of very low birth weight infants on recent secular trends in the prevalence of cerebral palsy.

OBJECTIVE To review recent secular trends in the prevalence of cerebral palsy in industrialized countries that have population-based cerebral palsy registries and to estimate such time-trends for the United States, where until recently such registries were absent. DATA SOURCES Recent epidemiologic studies of cerebral palsy published in peer-reviewed journals in English, and US vital data bearing on the principal demographic determinants of cerebral palsy--birth rates, the birth weight distributions, birth weight-specific mortality risk, and cerebral palsy risk among survivors. RESULTS Most epidemiologic studies from industrialized countries show a rise in the childhood prevalence of cerebral palsy in recent decades, largely because of the increasing contribution of children of low and very low birth weight to its prevalence. The only demographic determinant of cerebral palsy prevalence that is changing rapidly in the United States is survival of low birth weight and very low birth weight infants. Based on the magnitude of change in the survival of low and very low birth weight infants, it is estimated that childhood prevalence of cerebral palsy rose about 20% between 1960 and 1986 in the United States. CONCLUSION An apparently unavoidable side effect of the increasing success of newborn intensive care is a moderate rise in the childhood prevalence of cerebral palsy.