title: Maternal pregnancy levels of trans-nonachlor and oxychlordane and prevalence of cryptorchidism and hypospadias in boys.
abstract: BACKGROUND
  The etiologies of the male urogenital anomalies--cryptorchidism and hypospadias--are poorly understood. Given positive associations between chlordane isomers and testicular germ cell tumors, it is reasonable to assume that chlordanes might also be associated with other testicular dysgenesis syndrome disorders, namely cryptorchidism and hypospadias.
  
  
  OBJECTIVE
  To examine whether exposure to in utero chlordane is related to cryptorchidism and hypospadias, we evaluated levels of chlordane derivatives, trans-nonachlor and oxychlordane, among pregnant women enrolled in the Collaborative Perinatal Project (CPP).
  
  
  METHODS
  From 1959 to 1965, the CPP enrolled pregnant women at 12 U.S. medical centers. We analyzed serum trans-nonachlor and oxychlordane levels measured in third-trimester serum from the mothers of 217 sons with cryptorchidism, 197 sons with hypospadias, and 557 sons with neither condition. Adjusted odds ratios (ORs) and 95% confidence intervals were calculated using conditional logistic regression.
  
  
  RESULTS
  The quartile-specific ORs for cryptorchidism or hypospadias show no notable associations with trans-nonachlor or oxychlordane. Further, there were no significant trends with increasing quartile of maternal trans-nonachlor or oxychlordane level in either cryptorchidism or hypospadias (p-trend all > 0.45).
  
  
  CONCLUSIONS
  The results do not support an association between chlordane levels and cryptorchidism or hypospadias. It is unlikely that current chlordane exposure is related to the development of either anomaly, given that serum chlordane levels at the time of sample collection, the early 1960s, were considerably higher than levels at present.
authors.affiliation: Hormonal and Reproductive Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Rockville, Maryland 20852, USA. britton.trabert@nih.gov
authors.forename: Britton
authors.initials: B
authors.lastname: Trabert
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Longnecker
authors.forename: John W
authors.initials: JW
authors.lastname: Brock
authors.forename: Mark A
authors.initials: MA
authors.lastname: Klebanoff
authors.forename: Katherine A
authors.initials: KA
authors.lastname: McGlynn
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002706:Chlordan / Q000031:analogs & derivatives* / Q000097:blood / Q000633:toxicity; D015331:Cohort Studies; D003456:Cryptorchidism / Q000139:chemically induced / Q000453:epidemiology*; D005260:Female; D006801:Humans; D006843:Hydrocarbons, Chlorinated / Q000097:blood / Q000633:toxicity*; D007021:Hypospadias / Q000139:chemically induced / Q000453:epidemiology*; D007306:Insecticides / Q000097:blood / Q000633:toxicity*; D016015:Logistic Models; D008297:Male; D016017:Odds Ratio; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000139:chemically induced / Q000453:epidemiology*; D015995:Prevalence; D011446:Prospective Studies; D012307:Risk Factors; D014481:United States / Q000453:epidemiology; D055815:Young Adult
chemical_list: D006843:Hydrocarbons, Chlorinated; D007306:Insecticides; D002706:Chlordan; C008743:oxychlordane; C001870:nonachlor