Evaluation of sperm nuclear morphology in specimens with abnormal sperm chromatin structural assays.

Two recent tests have claimed to identify the subfertile male even when other semen parameters were normal: the sperm chromatin structure assay (SCSA) and abnormal sperm nuclear morphology using much higher magnification. The present study attempted to determine if having a high (> 30%) DNA fragmentation index (DFI), thus resulting in an abnormal SCSA test, is associated with a greater likelihood of sperm with abnormal nuclei. Four males with high DFI scores (57.6%, 65.4%, 31.0%, and 35.3%) had their nuclei evaluated by a complex microscope set-up that magnifies the sperm at least 6000x. The corresponding % of normal nuclei was 0%, 20.0%, 23.7% and 40.0%. The mean and median % of normal nuclei was 20.9+/-16.43 and 21.8, respectively. More studies of similarly matched refractory in vitro fertilization cases, where males have normal DFI scores, are needed to determine if having a high DFI index is associated with a lower percentage of normal nuclei.