title: Motor vehicle crashes during pregnancy and cerebral palsy during infancy: a longitudinal cohort analysis.
abstract: To assess the incidence of cerebral palsy among children born to mothers who had their pregnancy complicated by a motor vehicle crash.
  
  
  
  Retrospective longitudinal cohort analysis of children born from 1 April 2002 to 31 March 2012 in Ontario, Canada.
  
  
  
  Cases defined as pregnancies complicated by a motor vehicle crash and controls as remaining pregnancies with no crash.
  
  
  
  Subsequent diagnosis of cerebral palsy by age 3 years.
  
  
  
  A total of 1 325 660 newborns were analysed, of whom 7933 were involved in a motor vehicle crash during pregnancy. A total of 2328 were subsequently diagnosed with cerebral palsy, equal to an absolute risk of 1.8 per 1000 newborns. For the entire cohort, motor vehicle crashes correlated with a 29% increased risk of subsequent cerebral palsy that was not statistically significant (95% CI -16 to +110, p=0.274). The increased risk was only significant for those with preterm birth who showed an 89% increased risk of subsequent cerebral palsy associated with a motor vehicle crash (95% CI +7 to +266, p=0.037). No significant increase was apparent for those with a term delivery (95% CI -62 to +79, p=0.510). A propensity score-matched analysis of preterm births (n=4384) yielded a 138% increased relative risk of cerebral palsy associated with a motor vehicle crash (95% CI +27 to +349, p=0.007), equal to an absolute increase of about 10.9 additional cases per 1000 newborns (18.2 vs 7.3, p=0.010).
  
  
  
  Motor vehicle crashes during pregnancy may be associated with an increased risk of cerebral palsy among the subgroup of cases with preterm birth. The increase highlights a specific role for traffic safety advice in prenatal care.
authors.affiliation: Department of Medicine, University of Toronto, Toronto, Ontario, Canada Evaluative Clinical Sciences, Sunnybrook Research Institute, Toronto, Ontario, Canada Institute of Clinical Evaluative Sciences (ICES) in Ontario, Toronto, Ontario, Canada Institute for Health Policy Management and Evaluation Division of General Internal Medicine, University of Toronto, Toronto, Ontario, Canada Department of Obstetrics and Gynecology, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada.
authors.forename: Donald A
authors.initials: DA
authors.lastname: Redelmeier
authors.affiliation: Department of Medicine, University of Toronto, Toronto, Ontario, Canada Evaluative Clinical Sciences, Sunnybrook Research Institute, Toronto, Ontario, Canada Institute of Clinical Evaluative Sciences (ICES) in Ontario, Toronto, Ontario, Canada.
authors.forename: Faisal
authors.initials: F
authors.lastname: Naqib
authors.affiliation: Evaluative Clinical Sciences, Sunnybrook Research Institute, Toronto, Ontario, Canada Institute of Clinical Evaluative Sciences (ICES) in Ontario, Toronto, Ontario, Canada.
authors.forename: Deva
authors.initials: D
authors.lastname: Thiruchelvam
authors.affiliation: Department of Obstetrics and Gynecology, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada Department of Obstetrics and Gynecology, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Jon F
authors.initials: JF
authors.lastname: R Barrett
mesh_terms: D000063:Accidents, Traffic / Q000706:statistics & numerical data*; D000293:Adolescent; D000328:Adult; D002547:Cerebral Palsy / Q000453:epidemiology*; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008137:Longitudinal Studies; D008875:Middle Aged; D009864:Ontario / Q000453:epidemiology; D011247:Pregnancy; D047928:Premature Birth / Q000453:epidemiology; D012189:Retrospective Studies; D055815:Young Adult
keywords: car accident; cerebral palsy; motor vehicle trauma; prenatal care; preterm birth; traffic crash