title: The impact of semen processing on sperm parameters and pregnancy rates after intrauterine insemination.
abstract: BACKGROUND
  The objective of this retrospective study was to evaluate the effect of semen processing on computer analyzed semen parameters and pregnancy rates after intrauterine insemination (IUI).
  
  
  METHODS
  Over a two-year period, a total of 981 couples undergoing 2231 IUI cycles were evaluated and the freshly collected non-donor semen was analyzed before and after density gradient centrifugation (DGC).
  
  
  RESULTS
  DGC led to significant increases in sperm concentration by 66±74 ×106/mL (P=0.0001), percentage of motile sperm by 24±22% (P=0.0001), concentration motile by 27±58 ×106/mL (P=0.0001), and forward sperm progression by 18±14 µ/s (P=0.0001). In 95% of cases, there was a decrease in the total motile sperm count (TMSC), with an average decrease of 50±124% compared to pre-processed samples (P=0.0001). Importantly, the decrease in TMSC did not negatively affect pregnancy rates (P=0.45).
  
  
  CONCLUSIONS
  This study proves that DGC leads to significant increases in most sperm parameters, with the exception of TMSC. Remarkably, the decrease in TMSC did not affect the pregnancy rate. This should reassure clinicians when the TMSC is negatively affected by processing.
authors.affiliation: Department of Obstetrics and Gynecology, McGill University, Montreal, Canada - j.ruiter.ligeti@gmail.com.
authors.forename: Jacob
authors.initials: J
authors.lastname: Ruiter-Ligeti
authors.affiliation: Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: Chioma
authors.initials: C
authors.lastname: Agbo
authors.affiliation: Department of Obstetrics and Gynecology, McGill University, Montreal, Canada.
authors.forename: Michael
authors.initials: M
authors.lastname: Dahan
mesh_terms: D000328:Adult; D002499:Centrifugation, Density Gradient; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007315:Insemination, Artificial / Q000379:methods*; D008297:Male; D011247:Pregnancy; D018873:Pregnancy Rate; D012189:Retrospective Studies; D012661:Semen / Q000502:physiology*; D055101:Semen Analysis; D013076:Sperm Count; D013081:Sperm Motility / Q000502:physiology; D013094:Spermatozoa / Q000502:physiology*