Pre-natal factors in the origin of germ cell tumours of childhood.

The Manchester (England) Children's Tumour Registry is population-based with a high level of ascertainment. Pathologic review ensured diagnostic accuracy. Routine monitoring of annual incidence revealed a significant increase in germ cell tumours from approximately 1 per million person years to approximately 4. Analysis of the children's case records and their mothers' obstetric records showed an association between germ cell tumours and congenital malformations, particularly of the central nervous system, in the children themselves and in their stillborn sibs. An association between infections in pregnancy and early onset of tumours in the offspring was demonstrated. Other factors such as chronic illness in the mothers and drug-taking during pregnancy may be important, but further work is required to establish any definite associations.