Assessment of Sperm DNA Fragmentation in Patients with Partial Globozoospermia

Infertility is estimated to affect up to 15% of couples of reproductive age. Globozoospermia is a rare (incidence < 0.1%) but severe disorder in male infertility. It is characterized by the absence of acrosome in round-headed spermatozoa. Cases with partial globozoospermic are a group of patients whose semen samples show only a fraction with this typical head shape. It is possible that round-headed sperm may have an abnormal chromatin structure and/or DNA strand breaks. Moreover, sperm DNA fragmentation is shown to be associated with teratozoospermia. This study aimed to assess the sperm DNA fragmentation in the patients with partial globozoospermia. In this prospective cohort study, 77 subjects including 33 infertile men with round-headed sperm (above 20%) and 44 normozospermic men as control was recruited over a 30 month period. Semen examination was based on World Health Organization guidelines. Sperm chromatin structure assay (SCSA) and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay were done for evaluation of the chromatin structure. The analysis of sperm DNA fragmentation showed statistical differences between patients with partial globozoospermia and control group. Patients with partial globozoospermia had a higher mean level of DNA fragmentation than the men with normal spermogram in SCSA (26.57 ± 16.69 vs. 14.57 ± 9.24) and TUNEL (24.81 ± 18.68 vs. 11.50 ± 4.22) methods, respectively. The results of TUNEL and SCSA showed a strong relationship (r = 0.484; P < 0.001) in both groups. Some specific morphological abnormalities were shown to be predictive of chromatin alteration. The present study demonstrated that men with round-head sperm have elevated risk for DNA fragmentation in their sperm compared to control group. There are just some case reports about DNA fragmentation rate in men with globozoosprmia and further confirmation in a larger scale study is needed.