title: Number of children as a risk factor for low back pain in men and women.
abstract: OBJECTIVE
  To estimate the influence of the number of liveborn children on the risk of low back pain.
  
  
  METHODS
  The study design was a cross-sectional population-based survey. The 4,501 respondents to a postal survey were asked to provide data on the occurrence of low back pain and on any children they had. Data on some potential confounding variables were also obtained.
  
  
  RESULTS
  There was an increased risk of low back pain in those who were married compared with those who were unmarried, among both men (odds ratio 1.7) and women (odds ratio 1.6). Among married individuals, there was a linear trend of increasing risk with increasing numbers of children.
  
  
  CONCLUSIONS
  The risk of low back pain is related more to childrearing than to childbearing, although this effect might be partially mediated by unknown confounders associated with increasing family size.
authors.affiliation: University of Manchester Medical School, England.
authors.forename: A J
authors.initials: AJ
authors.lastname: Silman
authors.forename: S
authors.initials: S
authors.lastname: Ferry
authors.forename: A C
authors.initials: AC
authors.lastname: Papageorgiou
authors.forename: M I
authors.initials: MI
authors.lastname: Jayson
authors.forename: P R
authors.initials: PR
authors.lastname: Croft
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D001416:Back Pain / Q000453:epidemiology*; D003430:Cross-Sectional Studies; D005191:Family Characteristics; D005260:Female; D006801:Humans; D008161:Lumbosacral Region; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D010298:Parity; D015995:Prevalence; D012307:Risk Factors; D017678:Sex Distribution