title: Associations of prenatal and childhood antibiotic use with child body mass index at age 3 years.
abstract: Early-life antibiotic exposure, whether through prenatal or childhood antibiotic use, may contribute to increased child body mass. Associations of prenatal and childhood antibiotic use with body mass index z-score (BMIz) were evaluated at age 3 years.
  
  
  
  Electronic health records were utilized from 8,793 mothers and singleton children delivered at Geisinger Clinic in Pennsylvania between 2006 and 2012. Antibiotic orders were ascertained for mothers during pregnancy and for children through their age-3 BMI measurement. Linear mixed-effects regression models evaluated associations of prenatal and childhood antibiotic use with child BMIz.
  
  
  
  Prenatal antibiotic orders were not associated with child BMIz. Children in the three largest categories of lifetime antibiotic orders had higher BMIz compared with children with no orders; associations persisted when controlling for prenatal antibiotics (β [95% confidence interval]) (4-5 child orders: 0.090 [0.011 to 0.170]; 6 to 8: 0.113 [0.029 to 0.197]; ≥9: 0.175 [0.088 to 0.263]; trend P value <0.001). Two or more first-year orders were also associated with BMIz (1: 0.021 [-0.038 to 0.081]; 2: 0.088 [0.017 to 0.160]; ≥3: 0.104 [0.038 to 0.170]; trend P value < 0.001).
  
  
  
  Associations of early-life and lifetime childhood antibiotic use with increased child BMI highlight antibiotic exposure as a modifiable factor for reducing population-level excess weight.
authors.affiliation: Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA.|Geisinger Center for Health Research, Danville, Pennsylvania, USA.
authors.forename: Melissa N
authors.identifier: 0000-0002-5915-371X
authors.initials: MN
authors.lastname: Poulsen
authors.affiliation: Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Pollak
authors.affiliation: Geisinger Center for Health Research, Danville, Pennsylvania, USA.
authors.forename: Lisa
authors.initials: L
authors.lastname: Bailey-Davis
authors.affiliation: Geisinger Center for Health Research, Danville, Pennsylvania, USA.
authors.forename: Annemarie G
authors.initials: AG
authors.lastname: Hirsch
authors.affiliation: Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA.
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Glass
authors.affiliation: Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA.|Geisinger Center for Health Research, Danville, Pennsylvania, USA.|Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA.|Department of Medicine, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA.
authors.forename: Brian S
authors.initials: BS
authors.lastname: Schwartz
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000627:therapeutic use; D015992:Body Mass Index; D001835:Body Weight / Q000187:drug effects*; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D010414:Pennsylvania; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000503:physiopathology*; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents