title: Relationships between sperm motility characteristics assessed by the computer-aided sperm analysis (CASA) and fertilization rates in vitro.
abstract: OBJECTIVE
  Some studies have suggested that computer-aided sperm analysis (CASA) estimates of concentration and movement characteristics of progressively motile spermatozoa are related to fertilization rates in vitro. However, it has also been suggested that the greater number of motility parameters assessed by CASA does not imply more precision in predicting fertility. This study was carried out to investigate the relationships between the CASA estimates and fertilization rates in vitro.
  
  
  METHODS
  Semen quality analysis was performed using CASA in 136 in vitro fertilization-embryo transfer (IVF-ET) cycles with at least 3 oocytes collected. The CASA estimates before and after swim-up were compared between 108 cycles with fertilization rate > 50% ("good" group) and 28 cycles with fertilization rate < or = 50% ("poor" group).
  
  
  RESULTS
  Before swim-up, there were significant correlations between fertilization rates and CASA estimates, including amplitude of lateral head displacement (ALH) (r = .269), curvilinear velocity (VCL) (r = .297), straight line velocity (VSL) (r = .266), and rapid sprm movement (Rapid) (r = .243). There was also a significant correlation between the fertilization rates and straightness (STR) after swim-up (r = -0.178). As for sperm movement characteristics, there were significant differences of ALH (p < .005), VCL (p < .001), VSL (p < .005), and Rapid (p < .01) between "good" and "poor" groups before swim-up. After swim-up, there were significant differences of VCL (p < .005), average path velocity (VAP) (p < .005), and Rapid (p < .05) between the two groups.
  
  
  CONCLUSIONS
  These results indicate that some of the CASA estimates provide reliable estimation of the fertilizing ability of human sperm. There were significant differences of the two sperm movement characteristics, including VCL and Rapid (before and after swim-up), indicating that the total distance traveled by rapid sperm movement might be important in human sperm fertilizing abilities.
authors: Department of Obstetrics and Gynecology, Jichi Medical School, 3311-1, Yakushiji, Minamikawachi-machi, Tochigi 329-0498, Japan. sibahara@jichi.ac.jp
authors: Y
authors: Y
authors: Hirano
authors: H
authors: H
authors: Shibahara
authors: H
authors: H
authors: Obara
authors: T
authors: T
authors: Suzuki
authors: S
authors: S
authors: Takamizawa
authors: C
authors: C
authors: Yamaguchi
authors: H
authors: H
authors: Tsunoda
authors: I
authors: I
authors: Sato
mesh_terms: D048429:Cell Size; D005307:Fertilization in Vitro; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008297:Male; D011237:Predictive Value of Tests; D012661:Semen / Q000166:cytology; D013081:Sperm Motility / Q000502:physiology*; D013094:Spermatozoa / Q000166:cytology / Q000502:physiology; D013223:Statistics as Topic