title: Integrity of human sperm DNA assessed by the neutral comet assay and its relationship to semen parameters and clinical outcomes for the IVF-ET program.
abstract: OBJECTIVE
  To explore potential relationships between sperm DNA integrity and both semen parameters and clinical outcomes.
  
  
  METHODS
  Semen analysis of 498 samples was performed according to the 2010 criteria of the World Health Organization. The sperm DNA fragmentation Index (DFI) of the semen samples was assessed using a neutral comet assay.
  
  
  RESULTS
  Sperm DFI showed a significant correlation with semen parameters, including the patient's age, sperm viability, motility, morphology, and number of leukocytes (p<0.05). The sperm DFI values for asthenozoospermic (15.2%), oligoteratozoospermic (18.3%), asthenoteratozoospermic (17.5%), and oligoasthenoteratozoospermic semen samples (21.3%) were significantly higher than that observed in normozoospermic semen samples (10.5%, p<0.05). A sperm DFI value of 14% was used as a threshold of sperm DFI in assessing whether DNA was highly damaged. In 114 IVF-ET cycles, the fertilization rate of the sperm DFI <14% group (70 cycles, 61.7%) was significantly higher than that observed for the ≥14% group (44 cycles, 55.3%), but there was no difference in the other clinical outcomes between the two groups. In the ≥14% group, the pregnancy rates of the ICSI cycles (40.0%) and half-ICSI (44.0%) were higher than conventional IVF cycles (30.7%), but the difference was not statistically significant.
  
  
  CONCLUSIONS
  Along with the conventional semen analysis, the sperm DFI assessed using the comet assay was shown to improve the quality of the semen evaluation. To evaluate the precise effect of ICSI on pregnancy rates in the patients who demonstrate high sperm DFI values, further study is necessary.
authors.affiliation: ART Research Center, Seoul, Korea.
authors.forename: Hee-Jun
authors.initials: HJ
authors.lastname: Chi
authors.forename: Da-Yeon
authors.initials: DY
authors.lastname: Chung
authors.forename: Soon-Young
authors.initials: SY
authors.lastname: Choi
authors.forename: Jong-Hyun
authors.initials: JH
authors.lastname: Kim
authors.forename: Gi-Young
authors.initials: GY
authors.lastname: Kim
authors.forename: Jae-Seok
authors.initials: JS
authors.lastname: Lee
authors.forename: Hee-Sun
authors.initials: HS
authors.lastname: Lee
authors.forename: Myung-Hee
authors.initials: MH
authors.lastname: Kim
authors.forename: Sung-Il
authors.initials: SI
authors.lastname: Roh