title: Circumcision status and risk of sexually transmitted infection in young adult males: an analysis of a longitudinal birth cohort.
abstract: OBJECTIVE
  Previous research suggests that male circumcision may be a protective factor against the acquisition of sexually transmitted infections; however, studies examining this question have produced mixed results. The aim of this study was to examine the association between circumcision status and sexually transmitted infection risk using a longitudinal birth cohort study.
  
  
  METHODS
  Data were gathered as part of the Christchurch Health and Development Study, a 25-year longitudinal study of a birth cohort of New Zealand children. Information was obtained on: (1) the circumcision status of males in the cohort before 15 years old, (2) measures of self-reported sexually transmitted infection from ages 18 to 25 years, and (3) childhood, family, and related covariate factors.
  
  
  RESULTS
  Being uncircumcised had a statistically significant bivariate association with self-reported sexually transmitted infection. Adjustment for potentially confounding factors, including number of sexual partners and unprotected sex, as well as background and family factors related to circumcision, did not reduce the association between circumcision status and reports of sexually transmitted infection. Estimates of the population-attributable risk suggested that universal neonatal circumcision would have reduced rates of sexually transmitted infection in this cohort by 48.2%.
  
  
  CONCLUSIONS
  These findings suggest that uncircumcised males are at greater risk of acquiring sexually transmitted infection than circumcised males. Male circumcision may reduce the risk of sexually transmitted infection acquisition and transmission by up to one half, suggesting substantial benefits accruing from routine neonatal circumcision.
authors.affiliation: Christchurch Health and Development Study, Christchurch School of Medicine and Health Sciences, PO Box 4345, Christchurch, New Zealand. david.fergusson@chmeds.ac.nz
authors.forename: David M
authors.initials: DM
authors.lastname: Fergusson
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Boden
authors.forename: L John
authors.initials: LJ
authors.lastname: Horwood
mesh_terms: D000293:Adolescent; D000328:Adult; D002944:Circumcision, Male; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D012307:Risk Factors; D012749:Sexually Transmitted Diseases / Q000453:epidemiology*