title: Comparison of associations of maternal peri-pregnancy and paternal anthropometrics with child anthropometrics from birth through age 7 y assessed in the Danish National Birth Cohort.
abstract: BACKGROUND
  Maternal prepregnancy adiposity may influence child adiposity beyond the transmitted genetic effects, which, if true, may accelerate the obesity epidemic, but the evidence for this mechanism is inconsistent.
  
  
  OBJECTIVE
  The aim was to assess whether the associations of maternal body mass index (BMI) with child anthropometric measurements from birth through infancy and at 7 y of age exceed those of paternal associations.
  
  
  METHODS
  In the Danish National Birth Cohort, information on parental and child anthropometric measures is available for 30,655 trio families from maternal interviews during pregnancy and the postpartum period and from a 7-y follow-up. By using multiple linear and logistic regression models of child SD (z) scores of weight and BMI at birth, 5 mo, 12 mo, and 7 y of age, and of child overweight at age 7 y, we compared associations with maternal prepregnancy and postpartum BMI z scores and with paternal BMI z scores.
  
  
  RESULTS
  When comparing maternal-child and paternal-child BMI z score associations, the strongest associations were observed with mothers' BMI at birth [maternal and paternal BMI z scores: 0.143 (95% CI: 0.130, 0.155) and 0.017 (95% CI: 0.005, 0.029), respectively] and throughout infancy, but the relative difference in the associations declined by child age [for BMI z score at child age 7 y per maternal and paternal BMI z scores: 0.208 (95% CI: 0.196, 0.220) and 0.154 (95% CI: 0.143, 0.166), respectively]. At 7 y of age, ORs of child overweight were 2.30 (95% CI: 1.99, 2.67) by maternal overweight and 1.96 (95% CI: 1.74, 2.21) by paternal overweight. There were no differences between the results based on maternal BMI before and after pregnancy or on child's weight adjusted for length or height.
  
  
  CONCLUSIONS
  The associations of child weight and BMI with maternal BMI were stronger than with paternal BMI. The differences between the associations were strong at birth but declined with child aging.
authors.affiliation: Institute of Preventive Medicine, Frederiksberg and Bispebjerg University Hospital, Copenhagen, Denmark; Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Public Health, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; and Medical Research Council Integrative Epidemiology Unit, School of Social and Community Medicine, Bristol University, Bristol, United Kingdom tsoe0005@regionh.dk.
authors.forename: Thorkild Ia
authors.identifier: http://orcid.org/0000-0003-4821-430X
authors.initials: TIa
authors.lastname: Sørensen
authors.affiliation: Institute of Preventive Medicine, Frederiksberg and Bispebjerg University Hospital, Copenhagen, Denmark;
authors.forename: Teresa Adeltoft
authors.initials: TA
authors.lastname: Ajslev
authors.affiliation: Institute of Preventive Medicine, Frederiksberg and Bispebjerg University Hospital, Copenhagen, Denmark;
authors.forename: Lars
authors.initials: L
authors.lastname: Ängquist
authors.affiliation: Institute of Preventive Medicine, Frederiksberg and Bispebjerg University Hospital, Copenhagen, Denmark;
authors.forename: Camilla Schmidt
authors.initials: CS
authors.lastname: Morgen
authors.affiliation: Institute of Preventive Medicine, Frederiksberg and Bispebjerg University Hospital, Copenhagen, Denmark;
authors.forename: Ioana Gabriela
authors.initials: IG
authors.lastname: Ciuchi
authors.affiliation: Medical Research Council Integrative Epidemiology Unit, School of Social and Community Medicine, Bristol University, Bristol, United Kingdom.
authors.forename: George
authors.identifier: http://orcid.org/0000-0002-1407-8314
authors.initials: G
authors.lastname: Davey Smith
mesh_terms: D000328:Adult; D000367:Age Factors; D000886:Anthropometry; D001724:Birth Weight; D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003718:Denmark; D005220:Fathers; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009035:Mothers; D009765:Obesity / Q000150:complications; D016017:Odds Ratio; D050177:Overweight; D063766:Pediatric Obesity / Q000209:etiology; D011247:Pregnancy
keywords: child anthropometry; childhood overweight; intergenerational relations; intrauterine environment; maternal effects; parental BMI; parental overweight