title: Penetration of zona-free hamster oocytes using human sperm aspirated from the epididymis of men with congenital absence of the vas deferens: comparison with human in vitro fertilization.
abstract: OBJECTIVE
  To assess the ability of sperm aspirated from the epididymis of men with congenital absence of the vas deferens to penetrate zona-free hamster oocytes. To directly compare the performance of human epididymal sperm in the zona-free hamster oocyte sperm penetration assay (SPA) with the results of human in vitro fertilization (IVF).
  
  
  METHODS
  Sperm penetration assay was carried out with epididymal sperm retrieved microsurgically, and with ejaculated sperm obtained from fertile donors (internal controls). For direct comparison, SPA was performed with the same epididymal sperm sample used for IVF.
  
  
  METHODS
  Men with congenital absence of the vas deferens undergoing sperm aspiration as part of their infertility treatment and control donors who provided ejaculated sperm.
  
  
  RESULTS
  Epididymal sperm penetrated SPA with a score of 0% to 30%. The SPA scores for internal controls using ejaculated sperm was 30% to 71%. Linear regression analysis of the association between penetration scores in SPA and fertilization rate in IVF indicated a positive correlation that was highly significative.
  
  
  CONCLUSIONS
  These findings using SPA confirm previous reports on the fertilizing potential of human epididymal sperm and its ability to produce normal pregnancies. The good correlation between SPA and human IVF using epididymal sperm suggest that SPA is an excellent bioassay to test laboratory experimental conditions for improving fertilizing capacity of human epididymal sperm.
authors.affiliation: Department of Obstetrics and Gynecology, University of California, Irvine Medical Center, Orange 92668.
authors.forename: F J
authors.initials: FJ
authors.lastname: Rojas
authors.forename: A T
authors.initials: AT
authors.lastname: La
authors.forename: T
authors.initials: T
authors.lastname: Ord
authors.forename: P
authors.initials: P
authors.lastname: Patrizio
authors.forename: J P
authors.initials: JP
authors.lastname: Balmaceda
authors.forename: S J
authors.initials: SJ
authors.lastname: Silber
authors.forename: R H
authors.initials: RH
authors.lastname: Asch
mesh_terms: D000328:Adult; D000818:Animals; D006224:Cricetinae; D004822:Epididymis / Q000166:cytology*; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D007248:Infertility, Male / Q000209:etiology* / Q000628:therapy*; D008297:Male; D009865:Oocytes / Q000502:physiology*; D012044:Regression Analysis; D013084:Sperm-Ovum Interactions; D013094:Spermatozoa / Q000502:physiology*; D014649:Vas Deferens / Q000002:abnormalities*; D015044:Zona Pellucida / Q000502:physiology