Bilateral spastic cerebral palsy--a comparative study between southwest Germany and western Sweden. II: Epidemiology.

Epidemiological data of a collaborative study on children with bilateral spastic cerebral palsy (BSCP) between south-west Germany and western Sweden are reported. The study period covered the birth years 1975 to 1986. Overall, the rate of BSCP increased during the birth year periods 1975-77 and 1978-80, but decreased thereafter. The rise was due to an increase of BSCP in low-birthweight (LBW) children, especially very LBW (VLBW) children. Mortality rates in LBW, and particularly VLBW, children decreased significantly during the whole study period in both countries. The BSCP rate, after the initial increase, showed a decrease during the second half of the study period in LBW children. Results are interpreted in favour of a predominantly prenatal aetiology in normal-birthweight and of a predominantly peri- and neonatal aetiology in LBW children.