The overall rate of cerebral palsy excluding post-neonatal cases, has
remained relatively constant, varying between 1.93 and 2.27 per 1000 b
irths over the 20-year period between 1969 and 1988 in Avon. The rate
of the subgroup of spastic cerebral palsy varied from 1.40 to 1.78 per
1000 births over the same time period. In singletons the correspondin
g figures were 1.80-2.17 per 1000 births and 1.28-1.67 per 1000 births
, and in multiple births the figures were 7.12-8.80 per 1000 births an
d 7.12-8.44 per 1000 births. Although the overall rates have remained
fairly constant there was an increase in incidence in the later years
among children with low birthweight and short gestation.