title: Maternal life course socio-economic position and offspring body composition at birth in a multi-ethnic population.
abstract: BACKGROUND
  Size and body composition at birth may affect long-term health. Mean birthweight and body composition differ between ethnic groups living in Europe. We wanted to explore if this relates to differences in socio-economic conditions in country of origin and over the maternal life course.
  
  
  METHODS
  This is a population-based cohort study of healthy pregnant women living in Oslo, Norway. Data on maternal early life and present socio-economic position (SEP) were collected in early gestation, and SEP scores were extracted through two separate principal components analyses. The associations between maternal present SEP and four different offspring anthropometric measures at birth were assessed separately, stratified by maternal early life SEP (dichotomised score) and Human Development Index (HDI, a country-level socio-economic indicator) in the country of origin [high HDI (Reference), n = 287 and low HDI, n = 250].
  
  
  RESULTS
  A strong positive association between maternal present SEP and offspring birthweight was observed if maternal early life SEP was high, but not if maternal early life SEP was low (P < 0.001 for the interaction term). This interactional effect was observed in both HDI groups. Maternal life course SEP affected offspring birthweight mainly through an effect on length and sum of skin folds. Offspring of mothers with origin from low HDI countries had smaller abdominal circumference, possibly indicating less fat-free mass, regardless of maternal life course SEP.
  
  
  CONCLUSIONS
  Our results suggest that there are transgenerational effects of maternal past socio-economic conditions on offspring size and body composition at birth that modify the associations with present socio-economic factors.
authors: Department of Child and Adolescents Medicine, Akershus University Hospital, Lørenskog, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway; Norwegian Resource Centre for Women's Health, Oslo University Hospital, Oslo, Norway.
authors: Line
authors: L
authors: Sletner
authors: Anne Karen
authors: AK
authors: Jenum
authors: Kjersti
authors: K
authors: Mørkrid
authors: Siri
authors: S
authors: Vangen
authors: Ingar M
authors: IM
authors: Holme
authors: Kåre I
authors: KI
authors: Birkeland
authors: Britt
authors: B
authors: Nakstad
mesh_terms: D000328:Adult; D001724:Birth Weight / Q000502:physiology*; D001823:Body Composition / Q000502:physiology*; D002648:Child; D005260:Female; D006801:Humans; D009664:Norway / Q000453:epidemiology; D011247:Pregnancy; D012307:Risk Factors; D012923:Social Class
keywords: Socioeconomic factors; body composition; ethnic differences