title: Association of prenatal antibiotics with foetal size and cord blood leptin and adiponectin.
abstract: Early postnatal antibiotic use has been shown to promote excess weight gain, but it is unclear whether intrauterine exposure to antibiotics is associated with foetal growth and adiposity. The objective of this study was to examine associations of antibiotic prescription in each trimester of pregnancy with foetal size and adipokine levels at birth.
  
  
  
  In 2128 pregnant women from the pre-birth Project Viva cohort, from electronic medical records, we estimated antibiotic prescribing by timing during pregnancy. Outcomes were sex-specific birth weight-for-gestational-age z-score (BW/GA-z) and levels of umbilical cord leptin and adiponectin. We used linear regression models adjusted for maternal age, pre-pregnancy body mass index, parity, race/ethnicity, education, smoking during pregnancy, household income and child sex and additionally adjusted cord blood leptin and adiponectin models for gestation length.
  
  
  
  Of the 2128 women in our sample, 643 (30.2%) were prescribed with oral antibiotics during pregnancy. Mean (standard deviation) BW/GA-z was 0.17 (0.97), cord blood leptin was 9.0 ng mL-1(6.6) and cord blood adiponectin was 28.8 ng mL-1(6.8). Overall, antibiotic prescription in pregnancy was associated with lower BW/GA-z [multivariable adjusted β -0.11; 95% confidence interval {CI} -0.20, -0.01]. In trimester-specific analyses, only second trimester antibiotic prescription was associated with lower BW/GA-z (β -0.23; 95% CI -0.37, -0.08). Overall, antibiotic prescription in pregnancy was not associated with cord blood leptin or adiponectin levels. However, in trimester-specific analyses, third trimester antibiotic prescription was associated with higher cord blood leptin (β 2.28 ng mL-1; 95% CI 0.38, 4.17).
  
  
  
  Antibiotics in mid-pregnancy were associated with lower birth weight for gestational age, whereas third trimester antibiotics were associated with higher cord blood leptin.
authors.affiliation: Department of Epidemiology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD, USA.|Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins University, Baltimore, MD, USA.
authors.forename: N T
authors.initials: NT
authors.lastname: Mueller
authors.affiliation: Obesity Prevention Program, Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, MA, USA.
authors.forename: S L
authors.initials: SL
authors.lastname: Rifas-Shiman
authors.affiliation: Division of Translational Medicine, Department of Medicine, New York University Langone Medical Center, New York, NY, USA.|Department of Microbiology, New York University Langone Medical Center, New York, NY, USA.
authors.forename: M J
authors.initials: MJ
authors.lastname: Blaser
authors.affiliation: Obesity Prevention Program, Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, MA, USA.|Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
authors.forename: M W
authors.initials: MW
authors.lastname: Gillman
authors.affiliation: Obesity Prevention Program, Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, MA, USA.|Diabetes Unit, Massachusetts General Hospital, Boston, MA, USA.|Department of Medicine, Universite de Sherbrooke, Sherbrooke, Quebec, Canada.
authors.forename: M-F
authors.initials: MF
authors.lastname: Hivert
mesh_terms: D052242:Adiponectin / Q000097:blood*; D000328:Adult; D000900:Anti-Bacterial Agents / Q000009:adverse effects*; D001724:Birth Weight; D015992:Body Mass Index; D005260:Female; D005312:Fetal Blood / Q000378:metabolism*; D047109:Fetal Development / Q000187:drug effects*; D005865:Gestational Age; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D020738:Leptin / Q000097:blood*; D016014:Linear Models; D008297:Male; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects
chemical_list: C499918:ADIPOQ protein, human; D052242:Adiponectin; D000900:Anti-Bacterial Agents; D020738:Leptin
keywords: Adiponectin; antibiotics; foetal growth; leptin