title: The association between maternal smoking during pregnancy and childhood obesity persists to the age of 9-10 years.
abstract: BACKGROUND
  We previously reported that a number of factors related to maternal lifestyle during early pregnancy, including smoking, are associated with childhood obesity at 5 years of age. In the present study, we investigated whether the association with maternal smoking persisted to the age of 9-10 years.
  
  
  METHODS
  The study population comprised children born between April 1, 1991 and March 31, 1999, and their mothers. The dependent variables--childhood overweight and obesity at 5 and 9-10 years of age--were defined according to internationally acknowledged cut-off values. Maternal smoking during early pregnancy was used as the independent variable.
  
  
  RESULTS
  Mothers who completed a specifically designed questionnaire gave birth to a total of 1644 infants during the study period. Anthropometric data were collected from 1302 of these children during medical checkups at 9-10 years of age (follow-up rate: 79.2%). Maternal smoking during early pregnancy was associated with obesity in 9- to 10-year-old children (adjusted odds ratio, 1.91; 95% confidence interval, 1.03-3.53). However, the point estimates at the age of 9-10 years were considerably lower than those at the age of 5 years.
  
  
  CONCLUSIONS
  Our results suggest that fetal environment, including exposure to maternal smoking, continues to be associated with childhood obesity at the age of 9-10 years.
authors.affiliation: Department of Health Sciences, School of Medicine, University of Yamanashi, Chuo, Yamanashi, Japan.
authors.forename: Kohta
authors.initials: K
authors.lastname: Suzuki
authors.forename: Daisuke
authors.initials: D
authors.lastname: Ando
authors.forename: Miri
authors.initials: M
authors.lastname: Sato
authors.forename: Taichiro
authors.initials: T
authors.lastname: Tanaka
authors.forename: Naoki
authors.initials: N
authors.lastname: Kondo
authors.forename: Zentaro
authors.initials: Z
authors.lastname: Yamagata
mesh_terms: D001837:Body Weights and Measures; D002648:Child; D002675:Child, Preschool; D004032:Diet; D005260:Female; D015438:Health Behavior; D006801:Humans; D008019:Life Style; D009035:Mothers; D009765:Obesity / Q000453:epidemiology* / Q000209:etiology; D050177:Overweight / Q000453:epidemiology / Q000209:etiology; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000453:epidemiology* / Q000209:etiology; D011446:Prospective Studies; D012890:Sleep; D012907:Smoking / Q000009:adverse effects*