title: Ultrastructure of human sperm in men with congenital absence of the vas deferens: clinical implications.
abstract: OBJECTIVE
  To determine the ultrastructural features of epididymal and vasa efferentia sperm in men with congenital absence of the vas deferens.
  
  
  METHODS
  Prospective.
  
  
  METHODS
  University of California Irvine Center for Reproductive Health.
  
  
  METHODS
  Thirteen men with surgical diagnosis of congenital absence of the vas deferens undergoing epididymal and vasa efferentia aspiration for assisted reproductive technology procedures.
  
  
  RESULTS
  The morphological quality and the integrity of the spermatozoa aspirated from the extratesticular segment of the rete testis, the vasa efferentia, and the caput epididymis were always markedly superior to those of sperm aspirated from the corpus and cauda epididymis, where the vast majority, if not all, were degenerating or frankly necrotic. The aspirates obtained from the distal segments of the epididymis also contained large numbers of sperm-laden macrophages; these were instead absent or exceptional in the fluids aspirated from the pre-epididymal portions of the excurrent pathways and from the caput of the epididymis.
  
  
  CONCLUSIONS
  This study demonstrates that the ultrastructural morphology of spermatozoa obtained by aspiration from the rete testis, vasa efferentia, and caput epididymis of individuals with congenital absence of the vas deferens is indistinguishable from that of spermatozoa in the semen.
authors.affiliation: Department of Obstetrics and Gynecology, University of California, Irvine.
authors.forename: R H
authors.initials: RH
authors.lastname: Asch
authors.forename: P
authors.initials: P
authors.lastname: Patrizio
authors.forename: S J
authors.initials: SJ
authors.lastname: Silber
mesh_terms: D000013:Congenital Abnormalities / Q000453:epidemiology; D004822:Epididymis / Q000166:cytology / Q000502:physiology / Q000648:ultrastructure; D006801:Humans; D008297:Male; D008854:Microscopy, Electron; D011446:Prospective Studies; D013094:Spermatozoa / Q000502:physiology / Q000648:ultrastructure*; D014649:Vas Deferens / Q000002:abnormalities* / Q000502:physiology / Q000648:ultrastructure