title: Sperm processing by swim-up and density gradient is effective in elimination of sperm with DNA damage.
abstract: OBJECTIVE
  DNA damage may occur during sperm processing, thereby negatively influencing fertilizing ability of the sperm. The present study was designed to compare the effectiveness of gradient and swim-up, either alone or in combination, to eliminate sperm with DNA damage.
  
  
  METHODS
  A total of 51 subjects visiting the University infertility clinic with normozoospermic parameters, oligozoospermia and teratozoospermia were included. Semen characteristics were analysed by standard criteria; Terminal deoxy nucelotidyl transferase mediated dUTP nick end labeling assay was employed for DNA damage assessment.
  
  
  RESULTS
  The percentage of TUNEL positive sperm after sperm processing was significantly lower in normozoospermic (P < 0.05), oligozoospermic (P < 0.001) and teratozoospermic samples (P < 0.01). No difference was observed in the incidence of TUNEL positive sperm between the various techniques, suggesting that they are comparable.
  
  
  CONCLUSIONS
  Sperm preparation has been found to result in enrichment of sperm with intact chromatin, which is likely to improve the chances of achieving a viable pregnancy.
authors.affiliation: Division of Reproductive Medicine, Clinical Embryology Laboratory, Kasturba Medical College Manipal University, Manipal 576 104, India. varsh1981@gmail.com
authors.forename: Varshini
authors.initials: V
authors.lastname: Jayaraman
authors.forename: Dinesh
authors.initials: D
authors.lastname: Upadhya
authors.forename: Pratap Kumar
authors.initials: PK
authors.lastname: Narayan
authors.forename: Satish Kumar
authors.initials: SK
authors.lastname: Adiga
mesh_terms: D002499:Centrifugation, Density Gradient / Q000379:methods*; D004249:DNA Damage; D006801:Humans; D020287:In Situ Nick-End Labeling; D007248:Infertility, Male / Q000473:pathology; D008297:Male; D009845:Oligospermia / Q000235:genetics; D012016:Reference Values; D012661:Semen / Q000166:cytology*; D013076:Sperm Count; D013081:Sperm Motility / Q000235:genetics; D013094:Spermatozoa / Q000166:cytology / Q000502:physiology*