title: Birth weight, sex and childhood cancer: A report from the United Kingdom Childhood Cancer Study.
abstract: Birth weight has been linked to the risk of developing childhood cancer, in particular childhood leukaemia. However, despite many childhood cancers having a male predominance and boys generally weighing more than girls at birth few studies have reported sex-specific associations. The relationship between birth weight and childhood cancer risk was examined using information from a national case-control study. Children (0-14 years) newly diagnosed with cancer in GB were ascertained between 1991 and 1996 (n=3651) and for comparison, controls matched on sex, month and year of birth were identified from primary care population registers (n=6337). Birth weights were obtained from the Office of National Statistics for all targeted subjects born in England and Wales. Overall, cases were, on average, 30 g heavier at birth than controls (p=0.003) with differences seen by cancer type; those diagnosed with hepatic tumours weighing around 500 g less than controls at birth (p<0.0001) and those with leukaemia being, on average, 50 g heavier than those without (p=0.001). An interaction between birth weight and sex was found for acute leukaemia (chi(2)=11.2, p=0.04) and when data were stratified by sex, an association between high birth weight and risk of ALL was seen with girls (>4000 g, OR 1.86, 95% CI 1.38-2.50, chi(2) for trend 20.2, p<0.0001). Our results support the hypothesis that birth weight is an important determinant for childhood cancer. In addition, the data are consistent with the notion that childhood leukaemia has a prenatal origin.
authors.affiliation: Epidemiology & Genetics Unit, Department of Health Sciences and Hull & York Medical School, University of York, York, UK. alex.smith@egu.york.ac.uk
authors.forename: Alexandra
authors.initials: A
authors.lastname: Smith
authors.forename: Tracy
authors.initials: T
authors.lastname: Lightfoot
authors.forename: Jill
authors.initials: J
authors.lastname: Simpson
authors.forename: Eve
authors.initials: E
authors.lastname: Roman
mesh_terms: D000293:Adolescent; D001724:Birth Weight / Q000502:physiology*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D049690:History, Ancient; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D009369:Neoplasms / Q000453:epidemiology*; D012042:Registries; D012307:Risk Factors; D012737:Sex Factors; D006113:United Kingdom / Q000453:epidemiology