title: Factors relating to pregnancy and birth and the risk of childhood brain tumors: results from an Australian case-control study.
abstract: BACKGROUND
  Childhood brain tumors (CBT) are the leading cause of cancer death in children, yet their causes are largely known. This study investigated the association between maternal and birth characteristics and risk of CBT.
  
  
  METHODS
  Cases families were recruited from all 10 Australian pediatric oncology centers between 2005 and 2010. Control families were recruited via random-digit dialing, frequency matched to cases on the basis of child's age, sex, and State of residence. Maternal and birth characteristics of children were ascertained by questionnaires. Odds ratios (ORs) and 95% confidence intervals (CI) were estimated using unconditional logistic regression, adjusting for relevant confounders.
  
  
  RESULTS
  For this analysis, data on 319 case children and 1,079 control children were available. No association was found between risk of CBT and birth weight, fetal growth, birth order, gestational age, or maternal body mass index. The ORs for inadequate and excessive maternal gestational weight gain (GWG) (Institute of Medicine 2009 guidelines) were 1.8 (95% CI 1.2-2.6) and 1.4 (95% CI 1.0-2.1), respectively; similar findings for GWG were seen across categories of child's age, fetal growth, maternal body mass index and height, maternal smoking, and parental education. Risk of low grade glioma appeared increased with preterm birth (OR 1.6 (95% CI 0.8-3.1) and admission to neonatal intensive care (NICU) for >2 days (OR 1.7, 95% CI 0.9-3.6).
  
  
  CONCLUSIONS
  We found little evidence of associations between risk of CBT and most birth characteristics. The associations we observed with GWG, prematurity and NICU admission require corroboration in other studies.
authors.affiliation: Telethon Institute for Child Health Research, Centre for Child Health Research, University of Western Australia, Perth, Western Australia, Australia.
authors.forename: Kathryn R
authors.initials: KR
authors.lastname: Greenop
authors.forename: Eve M
authors.initials: EM
authors.lastname: Blair
authors.forename: Carol
authors.initials: C
authors.lastname: Bower
authors.forename: Bruce K
authors.initials: BK
authors.lastname: Armstrong
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Milne
mesh_terms: D000293:Adolescent; D001315:Australia; D001932:Brain Neoplasms / Q000209:etiology*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D016015:Logistic Models; D008297:Male; D011247:Pregnancy; D047928:Premature Birth; D012306:Risk; D015430:Weight Gain
keywords: birth weight; brain tumors; cancer; child; fetal growth; gestational weight gain; neonatal intensive care; pregnancy