RESUMO
The utility of sperm DNA testing remains controversial. However, it may be helpful in couples with unexplained failures of multiple assisted reproductive techniques and/or recurrent abortions. This study analysed 10,400 spermatozoa of 26 patients for sperm-head morphology with high-magnification microscopy, DNA fragmentation and sperm chromatin decondensation. A significant negative correlation was demonstrated between sperm-parameters and abnormal sperm-head morphology as assessed by high magnification (score 0 according to this study's classification): concentration (r=-0.41; P=0.03), motility (r=-0.42; P=0.03), morphology (r=-0.63; P=0.0008). No correlation was found with DNA fragmentation. However, the sperm chromatin-decondensation rate of score-0 spermatozoa was twice as high as the controls (19.5% versus 10.1%; P<0.0001). This observation suggests that score-0 spermatozoa should not be selected for intracytoplasmic sperm injection.