ANTENATAL RISK-FACTORS FOR MALIGNANT BRAIN-TUMORS IN NEW-SOUTH-WALES CHILDREN

A population-based case-control study of incident primary malignant br ain tumours diagnosed during 1985 to 1989 in children aged 0 to 14 yea rs was carried out in the coastal conurbation of New South Wales compr ising Sydney, Wollongong and Newcastle in the period 1988 to 1990. Per sonal interviews were conducted using a structured questionnaire with mothers of 82 cases and 164 control children individually matched to t he cases by sex and age. Among the hypotheses being examined were thos e related to exposure to parental tobacco smoke, N-nitroso compounds a nd possible protection from sources of vitamin C. No link was found wi th tobacco smoking by the mother before or during pregnancy. While exp osure during pregnancy of the mother to tobacco smoke of the father ap peared to double the risk of childhood brain tumours and a similar ris k was found for father (but not mother) smoking before the index pregn ancy, there was no ''dose-response'' and the increased risk was confin ed to data supplied by the mother (rather than the father himself). Th e risk of childhood brain tumours rose with reported increasing consum ption, during pregnancy, of cured meats, which have high levels of N-n itroso compounds (or their precursors), and fell with rising consumpti on of vegetables. No association was found between the risk of childho od brain tumours and family history of epilepsy, cancer, or tumours of the nervous system, parental irradiation, previous miscarriage or pro cedures carried out during pregnancy, maternal consumption of antihist amines, barbiturates or diuretics, or maternal contact with cats or fa rm-life during pregnancy.