title: Lower birth weight and increased body fat at school age in children prenatally exposed to modern pesticides: a prospective study.
abstract: BACKGROUND
  Endocrine disrupting chemicals have been hypothesized to play a role in the obesity epidemic. Long-term effects of prenatal exposure to non-persistent pesticides on body composition have so far not been investigated. The purpose of this study was to assess possible effects of prenatal exposure to currently used pesticides on children's growth, endocrine and reproductive function.
  
  
  METHODS
  In a prospective study of 247 children born by women working in greenhouses in early pregnancy, 168 were categorized as prenatally exposed to pesticides. At three months (n = 203) and at 6 to 11 years of age (n = 177) the children underwent a clinical examination and blood sampling for analysis of IGF-I, IGFBP3 and thyroid hormones. Body fat percentage at age 6 to 11 years was calculated from skin fold measurements. Pesticide related associations were tested by linear multiple regression analysis, adjusting for relevant confounders.
  
  
  RESULTS
  Compared to unexposed children birth weight and weight for gestational age were lower in the highly exposed children: -173 g (-322; -23), -4.8% (-9.0; -0.7) and medium exposed children: -139 g (-272; -6), -3.6% (-7.2; -0.0). Exposed (medium and highly together) children had significantly larger increase in BMI Z-score (0.55 SD (95% CI: 0.1; 1.0) from birth to school age) and highly exposed children had 15.8% (0.2; 34.6) larger skin folds and higher body fat percentage compared to unexposed. If prenatally exposed to both pesticides and maternal smoking (any amount), the sum of four skin folds was 46.9% (95% CI: 8.1; 99.5) and body fat percentage 29.1% (95% CI: 3.0; 61.4) higher. There were subtle associations between exposure and TSH Z-score -0.66(-1.287; -0.022) and IGF-I Z-score (girls: -0.62(-1.0; -0.22), boys: 0.38(-0.03; 0.79)), but not IGFBP3.
  
  
  CONCLUSIONS
  Occupational exposure to currently used pesticides may have adverse effects in spite of the added protection offered to pregnant women. Maternal exposure to combinations of modern, non-persistent pesticides during early pregnancy was associated with affected growth, both prenatally and postnatally. We found a biphasic association with lower weight at birth followed by increased body fat accumulation from birth to school age. We cannot rule out some residual confounding due to differences in social class, although this was adjusted for. Associations were stronger in highly exposed than in medium exposed children, and effects on body fat content at school age was potentiated by maternal smoking in pregnancy.
authors.affiliation: University Dept, of Growth and Reproduction, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen Ø, Denmark. cwv@rh.regionh.dk
authors.forename: Christine
authors.initials: C
authors.lastname: Wohlfahrt-Veje
authors.forename: Katharina M
authors.initials: KM
authors.lastname: Main
authors.forename: Ida M
authors.initials: IM
authors.lastname: Schmidt
authors.forename: Malene
authors.initials: M
authors.lastname: Boas
authors.forename: Tina K
authors.initials: TK
authors.lastname: Jensen
authors.forename: Philippe
authors.initials: P
authors.lastname: Grandjean
authors.forename: Niels E
authors.initials: NE
authors.lastname: Skakkebæk
authors.forename: Helle R
authors.initials: HR
authors.lastname: Andersen
mesh_terms: D000273:Adipose Tissue / Q000254:growth & development / Q000503:physiopathology; D000328:Adult; D001823:Body Composition; D015992:Body Mass Index; D001835:Body Weight; D002648:Child; D015331:Cohort Studies; D003718:Denmark / Q000453:epidemiology; D005260:Female; D005865:Gestational Age; D006801:Humans; D007223:Infant; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D016014:Linear Models; D008163:Luminescent Measurements; D008297:Male; D018811:Maternal Exposure; D009765:Obesity / Q000453:epidemiology; D016273:Occupational Exposure; D010575:Pesticides / Q000633:toxicity*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000139:chemically induced* / Q000453:epidemiology*; D011446:Prospective Studies; D011863:Radioimmunoassay; D012907:Smoking; D013963:Thyroid Hormones / Q000097:blood
chemical_list: D018972:Insulin-Like Growth Factor Binding Protein 3; D010575:Pesticides; D013963:Thyroid Hormones; D007334:Insulin-Like Growth Factor I