title: Prenatal mercury exposure and birth outcomes.
abstract: BACKGROUND
  Results regarding the association between mercury exposure and anthropometry at birth, gestational length and placental weight are inconsistent, as is the role of seafood intake in these associations.
  
  
  OBJECTIVE
  We assessed whether prenatal mercury exposure is associated with anthropometry at birth, placental weight and gestational length in a population with a relatively high exposure to mercury from seafood consumption.
  
  
  METHODS
  Total mercury (T-Hg) was determined in cord blood from 1869 newborns with birth outcome measures, within the Spanish multicenter INMA cohort from 2004 to 2008. We adjusted cohort specific linear and Cox regression models to evaluate the association between T-Hg and birth anthropometry (weight, length, and head circumference), placental weight and gestational length. Non-spontaneous labor was taken to be censoring in the survival analysis. Final estimates were obtained using meta-analysis.
  
  
  RESULTS
  Geometric mean T-Hg was 8.2μg/L. A doubling of T-Hg was associated with a 7.7g decrease in placental weight (95% CI: -13.6, -1.8) and marginally with head circumference (beta: -0.052cm, 95% CI: -0.109, 0.005). T-Hg was also inversely related to weight and length, although with weaker estimates. Mercury exposure was not associated with the length of gestation. The inverse relation between T-Hg and growth was enhanced when the intake of different seafood groups was adjusted for in the models.
  
  
  CONCLUSIONS
  Prenatal mercury exposure may be associated with reduced placental and fetal growth. Confounding by fish intake should be considered when assessing these relationships.
authors.affiliation: Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Spain; Epidemiology and Environmental Health Joint Research Unit, FISABIO-Universitat Jaume I-Universitat de València, Valencia, Spain. Electronic address: murcia_mar@gva.es.
authors.forename: Mario
authors.initials: M
authors.lastname: Murcia
authors.affiliation: Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Spain; Epidemiology and Environmental Health Joint Research Unit, FISABIO-Universitat Jaume I-Universitat de València, Valencia, Spain; Nursing Department, Universitat de València, Valencia, Spain.
authors.forename: Ferran
authors.initials: F
authors.lastname: Ballester
authors.affiliation: ISGlobal, Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain; Universitat Pompeu Fabra, Barcelona, Spain.
authors.forename: Ashley Michel
authors.initials: AM
authors.lastname: Enning
authors.affiliation: Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Spain; Epidemiology and Environmental Health Joint Research Unit, FISABIO-Universitat Jaume I-Universitat de València, Valencia, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Iñiguez
authors.affiliation: Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Spain; ISGlobal, Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain; Universitat Pompeu Fabra, Barcelona, Spain; Harvard T.H. Chan School of Public Health, Boston, USA.
authors.forename: Damaskini
authors.initials: D
authors.lastname: Valvi
authors.affiliation: Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Spain; Public Health Division of Gipuzkoa, San Sebastián, Spain; Health Research Institute (BIODONOSTIA), San Sebastián, Spain.
authors.forename: Mikel
authors.initials: M
authors.lastname: Basterrechea
authors.affiliation: Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Spain; Epidemiology and Environmental Health Joint Research Unit, FISABIO-Universitat Jaume I-Universitat de València, Valencia, Spain; Medicine Department, Universitat Jaume I, Castelló de la Plana, Spain.
authors.forename: Marisa
authors.initials: M
authors.lastname: Rebagliato
authors.affiliation: Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Spain; Universidad Miguel Hernández, San Juan de Alicante, Spain.
authors.forename: Jesús
authors.initials: J
authors.lastname: Vioque
authors.affiliation: OSI Goierri-Alto Urola, Centro de Salud de Azkoitia, Spain.
authors.forename: Maite
authors.initials: M
authors.lastname: Maruri
authors.affiliation: Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Spain; IUOPA-Universidad de Oviedo, Spain.
authors.forename: Adonina
authors.initials: A
authors.lastname: Tardon
authors.affiliation: Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Spain; Pediatric Unit, Hospital San Agustin, Aviles, Spain.
authors.forename: Isolina
authors.initials: I
authors.lastname: Riaño-Galán
authors.affiliation: Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Spain; ISGlobal, Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain; Universitat Pompeu Fabra, Barcelona, Spain.
authors.forename: Martine
authors.initials: M
authors.lastname: Vrijheid
authors.affiliation: Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Spain; Epidemiology and Environmental Health Joint Research Unit, FISABIO-Universitat Jaume I-Universitat de València, Valencia, Spain.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Llop
mesh_terms: D000328:Adult; D000818:Animals; D049628:Body Size; D004785:Environmental Pollutants / Q000032:analysis*; D005260:Female; D005312:Fetal Blood / Q000737:chemistry; D005399:Fishes; D005506:Food Contamination; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D018811:Maternal Exposure; D008431:Maternal-Fetal Exchange; D008628:Mercury / Q000032:analysis*; D010929:Placentation; D011247:Pregnancy
chemical_list: D004785:Environmental Pollutants; D008628:Mercury
keywords: Birth weight; Diet, food, and nutrition; Gestational age; Maternal exposure; Mercury; Placentation