title: Prenatal Phthalate Exposures and Body Mass Index Among 4- to 7-Year-old Children: A Pooled Analysis.
abstract: BACKGROUND
  Phthalates are hypothesized to cause obesity, but few studies have assessed whether prenatal phthalate exposures are related to childhood body mass index (BMI).
  
  
  METHODS
  We included 707 children from three prospective cohort studies enrolled in the US between 1998 and 2006 who had maternal urinary phthalate metabolite concentrations measured during pregnancy, and measures of weight and height at ages 4 to 7 years. We calculated age- and sex-standardized BMI z scores and classified children with BMI percentiles ≥85 as overweight/obese. We used mixed effects regression models to estimate associations between a 1 standard deviation increase in natural log phthalate metabolite concentrations and BMI z scores and overweight/obesity. We estimated associations in multiple metabolite models adjusted for confounders, and evaluated heterogeneity of associations by child's sex, race/ethnicity, and cohort.
  
  
  RESULTS
  Mono-3-carboxypropyl phthalate concentrations were positively associated with overweight/obese status in children (odds ratio [95% credible interval] = 2.1 [1.2, 4.0]) but not with BMI z scores (β = -0.02 [-0.15, 0.11]). We did not observe evidence of obesogenic effects for other metabolites. However, monoethyl phthalate and summed di-(2-ethylhexyl) phthalate metabolites (∑DEHP) concentrations were inversely associated with BMI z scores among girls (monoethyl phthalate beta = -0.14 [-0.28, 0.00]; ∑DEHP beta = -0.12 [-0.27, 0.02]).
  
  
  CONCLUSIONS
  Maternal urinary mono-3-carboxypropyl phthalate, a nonspecific metabolite of several phthalates, was positively associated with childhood overweight/obesity. Metabolites of diethyl phthalate and DEHP were associated with lower BMI in girls but not in boys, suggesting that prenatal exposures may have sexually dimorphic effects on physical development.
authors.affiliation: From the aDepartment of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC; bDepartment of Epidemiology, Brown University School of Public Health, Brown University, Providence, RI; cDepartment of Environmental Health Sciences, Columbia Center for Children's Environmental Health, Mailman School of Public Health, Columbia University, New York, NY; dDepartment of Nutrition, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC; eDivision of General and Community Pediatrics, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH; fDivision of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA; gDepartment of Community and Preventative Medicine, Mount Sinai School of Medicine, New York, NY; hChild and Family Research Institute, BC Children's and Women's Hospital, Vancouver, Canada; iFaculty of Health Sciences, Simon Fraser University, Burnaby, Canada; jDepartment of Biostatistics, Gillings School of Global Public Health, and Carolina Population Center, University of North Carolina, Chapel Hill, NC; and kDepartment of Epidemiology, Mailman School of Public Health, Columbia University, New York, NY.
authors.forename: Jessie P
authors.initials: JP
authors.lastname: Buckley
authors.forename: Stephanie M
authors.initials: SM
authors.lastname: Engel
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Braun
authors.forename: Robin M
authors.initials: RM
authors.lastname: Whyatt
authors.forename: Julie L
authors.initials: JL
authors.lastname: Daniels
authors.forename: Michelle A
authors.initials: MA
authors.lastname: Mendez
authors.forename: David B
authors.initials: DB
authors.lastname: Richardson
authors.forename: Yingying
authors.initials: Y
authors.lastname: Xu
authors.forename: Antonia M
authors.initials: AM
authors.lastname: Calafat
authors.forename: Mary S
authors.initials: MS
authors.lastname: Wolff
authors.forename: Bruce P
authors.initials: BP
authors.lastname: Lanphear
authors.forename: Amy H
authors.initials: AH
authors.lastname: Herring
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Rundle
mesh_terms: D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004051:Diethylhexyl Phthalate / Q000031:analogs & derivatives / Q000652:urine; D005260:Female; D006801:Humans; D008297:Male; D050177:Overweight / Q000453:epidemiology; D063766:Pediatric Obesity / Q000453:epidemiology*; D010795:Phthalic Acids / Q000652:urine; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000453:epidemiology*; D011446:Prospective Studies; D012737:Sex Factors
chemical_list: D010795:Phthalic Acids; C479069:mono(2-ethyl-5-hydroxyhexyl) phthalate; C575690:mono-isobutyl phthalate; C581825:monoethyl phthalate; D004051:Diethylhexyl Phthalate; C016599:mono-(2-ethylhexyl)phthalate; C007379:diethyl phthalate