title: Relation between in Utero Arsenic Exposure and Birth Outcomes in a Cohort of Mothers and Their Newborns from New Hampshire.
abstract: Studies suggest that arsenic exposure influences birth outcomes; however, findings are mixed.
  
  
  
  We assessed in utero arsenic exposure in relation to birth outcomes and whether maternal prepregnancy weight and infant sex modified the associations.
  
  
  
  Among 706 mother-infant pairs exposed to low levels of arsenic through drinking water and diet, we assessed in utero arsenic exposure using maternal second-trimester urinary arsenic, maternal prepregnancy weight through self-report, and birth outcomes from medical records.
  
  
  
  Median (interquartile range) of total urinary arsenic [tAs; inorganic arsenic (iAs) + monomethylarsonic acid (MMA) + dimethylarsinic acid (DMA)] was 3.4 μg/L (1.7-6.0). In adjusted linear models, each doubling of tAs was associated with a 0.10-cm decrease (95% CI: -0.19, -0.01) in head circumference. Results were similar for MMA and DMA. Ln(tAs) and ln(DMA) were positively associated with birth length in infant males only; among males, each doubling of tAs was associated with a 0.28-cm increase (95% CI: 0.09, 0.46) in birth length (pinteraction = 0.04). Results were similar for DMA. Additionally, arsenic exposure was inversely related to ponderal index, and associations differed by maternal weight. Each ln(tAs) doubling of tAs was associated with a 0.55-kg/m3 lower (95% CI: -0.82, -0.28, p < 0.001) ponderal index for infants of overweight/obese, but not normal-weight, mothers (pinteraction < 0.01). Finally, there was a significant interaction between maternal weight status, infant sex, and arsenic exposure on birth weight (pinteraction = 0.03). In girls born of overweight/obese mothers, each doubling of tAs was associated with a 62.9-g decrease (95% CI: -111.6, -14.2) in birth weight, though the association was null in the other strata.
  
  
  
  Low-level arsenic exposure may affect fetal growth, and the associations may be modified by maternal weight status and infant sex.
  
  
  
  Gilbert-Diamond D, Emond JA, Baker ER, Korrick SA, Karagas MR. 2016. Relation between in utero arsenic exposure and birth outcomes in a cohort of mothers and their newborns from New Hampshire. Environ Health Perspect 124:1299-1307; http://dx.doi.org/10.1289/ehp.1510065.
authors.affiliation: Department of Epidemiology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA.
authors.forename: Diane
authors.initials: D
authors.lastname: Gilbert-Diamond
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Emond
authors.forename: Emily R
authors.initials: ER
authors.lastname: Baker
authors.forename: Susan A
authors.initials: SA
authors.lastname: Korrick
authors.forename: Margaret R
authors.initials: MR
authors.lastname: Karagas
mesh_terms: D005260:Female; D006801:Humans; D007231:Infant, Newborn; D011247:Pregnancy; D001151:Arsenic / Q000378:metabolism; D004785:Environmental Pollutants / Q000378:metabolism; D018811:Maternal Exposure / Q000706:statistics & numerical data; D009513:New Hampshire / Q000453:epidemiology; D011256:Pregnancy Outcome / Q000453:epidemiology
chemical_list: D001151:Arsenic; D004785:Environmental Pollutants