title: Serum persistent organic pollutants and duration of lactation among Mexican-American women.
abstract: BACKGROUND
  Research suggests that estrogenic endocrine-disrupting chemicals interfere with lactation.
  
  
  OBJECTIVE
  (1) to determine if estrogenic persistent organic pollutants (POPs) are associated with shortened lactation duration; (2) to determine whether previous breastfeeding history biases associations.
  
  
  RESULTS
  We measured selected organochlorines and polychlorinated biphenyls (p, p'-DDE, p, p'-DDT, o, p'-DDT, beta-hexachlorocyclohexane, hexachlorobenzene, and PCBs 44, 49, 52, 118, 138, 153, and 180) in serum from 366 low-income, Mexican-American pregnant women living in an agricultural region of California and assessed breastfeeding duration by questionnaires. We found no association between DDE, DDT, or estrogenic POPs with shortened lactation duration, but rather associations for two potentially estrogenic POPs with lengthened lactation duration arose (HR [95% CI]: 0.6 [0.4, 0.8] for p, p'-DDE & 0.8 [0.6, 1.0] for PCB 52). Associations between antiestrogenic POPs (PCBs 138 and 180) and shortened lactation duration were attributed to a lactation history bias.
  
  
  CONCLUSIONS
  Estrogenic POPs were not associated with shortened lactation duration, but may be associated with longer lactation duration.
authors.affiliation: Center for Children's Environmental Health Research, School of Public Health, University of California, Berkeley, CA 94704, USA.
authors.forename: Rosana H
authors.initials: RH
authors.lastname: Weldon
authors.forename: Monique
authors.initials: M
authors.lastname: Webster
authors.forename: Kim G
authors.initials: KG
authors.lastname: Harley
authors.forename: Asa
authors.initials: A
authors.lastname: Bradman
authors.forename: Laura
authors.initials: L
authors.lastname: Fenster
authors.forename: Mark D
authors.initials: MD
authors.lastname: Davis
authors.forename: Alan
authors.initials: A
authors.lastname: Hubbard
authors.forename: Dana B
authors.initials: DB
authors.lastname: Barr
authors.forename: Nina
authors.initials: N
authors.lastname: Holland
authors.forename: Brenda
authors.initials: B
authors.lastname: Eskenazi
mesh_terms: D000293:Adolescent; D000328:Adult; D002140:California; D052244:Endocrine Disruptors / Q000097:blood / Q000633:toxicity*; D004967:Estrogens / Q000097:blood / Q000633:toxicity*; D005260:Female; D006801:Humans; D006843:Hydrocarbons, Chlorinated / Q000097:blood / Q000633:toxicity*; D053208:Kaplan-Meier Estimate; D007774:Lactation / Q000097:blood / Q000187:drug effects* / Q000208:ethnology; D008137:Longitudinal Studies; D017058:Mexican Americans; D008875:Middle Aged; D010575:Pesticides / Q000097:blood / Q000633:toxicity; D011078:Polychlorinated Biphenyls / Q000097:blood / Q000633:toxicity*; D011247:Pregnancy; D025341:Principal Component Analysis; D016016:Proportional Hazards Models; D057566:Self Report; D013997:Time Factors; D055815:Young Adult
chemical_list: D052244:Endocrine Disruptors; D004967:Estrogens; D006843:Hydrocarbons, Chlorinated; D010575:Pesticides; D011078:Polychlorinated Biphenyls