title: Early and late long-term effects of vasectomy on serum testosterone, dihydrotestosterone, luteinizing hormone and follicle-stimulating hormone levels.
abstract: OBJECTIVE
  We investigated whether the association between vasectomy and prostate cancer has a hormonal basis.
  
  
  METHODS
  We examined serum testosterone, dihydrotestosterone, luteinizing hormone and follicle-stimulating hormone levels by radioimmunoassay on 91 pairs of men who did and did not undergo vasectomy.
  
  
  RESULTS
  Men who underwent vasectomy 10 to 19 years previously had higher dihydrotestosterone levels than age matched controls. In men who underwent vasectomy 20 years or more ago testosterone was higher than in corresponding controls. No statistically significant difference in luteinizing hormone and follicle-stimulating hormone levels was noted between the men who had had vasectomy and controls.
  
  
  CONCLUSIONS
  Our results indirectly support the hypothesis that there is an elevated risk of prostate cancer among men who underwent vasectomy 20 or more years previously.
mesh_terms: D013196:Dihydrotestosterone / Q000097:blood*; D005640:Follicle Stimulating Hormone / Q000097:blood*; D006801:Humans; D007986:Luteinizing Hormone / Q000097:blood*; D008297:Male; D008875:Middle Aged; D013739:Testosterone / Q000097:blood*; D013997:Time Factors; D014659:Vasectomy
chemical_list: D013196:Dihydrotestosterone; D013739:Testosterone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone