BACKGROUND: From 1993 to 1997 we conducted two population-based case-control 
studies on childhood cancer and a variety of potential risk factors in Germany. 
One case group involved children under the age of 15 years having a tumor of the 
central nervous system (CNS).
PROCEDURE: For both studies, one conducted in the northwestern area of Germany, 
the other covering the whole of West Germany, incident cases were identified 
from the nationwide German Childhood Cancer Registry, and controls were randomly 
selected from complete population registration files.
RESULTS: In total 466 pediatric CNS tumor cases and 2,458 controls were 
available for analyses. We observed only few positive associations, namely, 
between CNS tumors and low birth weight [<2,500 g; odds ratio (OR), 1.73; 95% 
confidence interval (CI), 1.06-2.84], between ependymoma and maternal smoking 
during pregnancy (>10 cigarettes per day: OR, 4.71; 95% CI, 1.69-13.1), and 
between astrocytoma and exposure to wood preservatives (OR, 1.91; 95% CI, 
1.22-3.01). CNS tumors were not associated with high birth weight, duration of 
breast feeding, maternal age at time of delivery, duration of gestation, 
previous fetal losses, paternal smoking during pregnancy, maternal alcohol 
consumption, the child's exposure to pesticides, maternal diagnostic X-ray 
examinations during pregnancy, X-ray examinations of the child, or exposure to 
residential magnetic fields.
CONCLUSIONS: Despite the large study population, we found only few factors that 
were associated with CNS tumors or one of the morphological subgroups. 
Therefore, our results suggest that aspects of the prenatal and neonatal period 
play only a minor role in the etiology of pediatric CNS tumors.