title: Maternal smoking in pregnancy, fetal development, and childhood asthma.
abstract: OBJECTIVE
  We examined the relationships among maternal smoking in pregnancy, fetal development, and the risk of asthma in childhood.
  
  
  METHODS
  We conducted a population-based cohort study, where all 58 841 singleton births were followed for 7 years using nationwide registries.
  
  
  RESULTS
  Maternal smoking increased the risk of asthma (adjusted odds ratio = 1.35; 95% confidence interval = 1.13, 1.62 for high exposure). Low birthweight and preterm delivery increased the risk of asthma at the age of 7, whereas being small for gestational age did not.
  
  
  CONCLUSIONS
  Maternal smoking in pregnancy increases the risk of asthma during the first 7 years of life, and only a small fraction of the effect seems to be mediated through fetal growth.
authors.affiliation: Institute of Occupational Health, The University of Birmingham, Birmingham, United Kingdom. j.jaakkola@bham.ac.uk
authors.forename: Jouni J K
authors.initials: JJ
authors.lastname: Jaakkola
authors.forename: Mika
authors.initials: M
authors.lastname: Gissler
mesh_terms: D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000453:epidemiology* / Q000209:etiology; D001724:Birth Weight / Q000187:drug effects; D015984:Causality; D002648:Child; D002675:Child, Preschool; D005260:Female; D005317:Fetal Growth Retardation / Q000139:chemically induced; D005387:Finland / Q000453:epidemiology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D008423:Maternal Age; D008431:Maternal-Fetal Exchange; D016017:Odds Ratio; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D012137:Respiratory System / Q000187:drug effects; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects* / Q000453:epidemiology