title: Maternal smoking during pregnancy, behavioral problems and school performances of their school-aged children.
abstract: BACKGROUND
  Child behavior and school performance is influenced by many genetic and environmental factors including prenatal exposure to chemical neurotoxins contained in cigarette smoke. The European Longitudinal Study of Pregnancy and Childhood (ELSPAC) prospective study which in the Czech Republic incorporates a cohort of children born in the years 1991/2 in Brno city and the Znojmo district also allows to analyze the relationships between prenatal cigarette smoke exposure and the occurrence of behavior and learning disorders.
  
  
  METHODS
  Using questionnaires repeatedly filled in by teachers and investigation protocols performed by research team workers data for the Brno sample of children was collected on the occurrence of signs indicating more serious problems with school assignment fulfilling and behavior disorders in the childrens' 8, 11 and 13 years of age. According to mothers' statements about their smoking behavior during pregnancy, the children were divided into two groups: prenatally exposed and non-exposed. The frequency differences of individual traits were evaluated in the SPSS statistical program (Pearson's chi2 test and linear associations, probability relations).
  
  
  RESULTS
  In the ELSPAC study set the occurrence of inferior schoolwork performance evaluated based on term-report grades was more frequent in children prenatally exposed to mothers' smoking, along with more frequently diagnosed disorders which to significant extent implicate these inferior results and also special care needs occurred more frequently when compared to their peers born to non-smoking mothers. In the prenatally exposed subset also more frequent occurrence of various signs characterizing behavior disorders including attention disorders, hyperactivity, aggressiveness and signs of delinquency behavior were recorded.
  
  
  CONCLUSIONS
  The Czech ELSPAC cohort confirmed the results of other studies; within it was documented that children born to smoking mothers have more frequent behavioral problems and problems with fulfilling their school assignments in the school age period.
authors.affiliation: Research Institute of Preventive and Social Paediatrics, Faculty of Medicine, Masaryk University, Brno, Czech Republic. lubomir.kukla@tiscali.cz
authors.forename: Lubomir
authors.initials: L
authors.lastname: Kukla
authors.forename: Drahoslava
authors.initials: D
authors.lastname: Hrubá
authors.forename: Mojmír
authors.initials: M
authors.lastname: Tyrlík
mesh_terms: D000293:Adolescent; D000328:Adult; D019958:Attention Deficit and Disruptive Behavior Disorders / Q000453:epidemiology*; D016009:Chi-Square Distribution; D002648:Child; D018153:Czech Republic / Q000453:epidemiology; D004521:Educational Measurement; D005260:Female; D006801:Humans; D016014:Linear Models; D008137:Longitudinal Studies; D009035:Mothers; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D011446:Prospective Studies; D012907:Smoking / Q000009:adverse effects* / Q000453:epidemiology; D011795:Surveys and Questionnaires