OBJECTIVETo investigate changes in sperm chromosome and sperm DNA integrity of infertile males.

METHODSThe level of DNA fragmentation was determined by Sperm Chromatin Dispersion (SCD) test in infertile males with idiopathic severe oligoasthenozoospermia (ISOA, n= 19), couples with unexplained recurrent miscarriage (URM, n= 38) and adult healthy fertile men (control group, n= 32). Multi-color fluorescence in situ hybridization (FISH) was performed with probes specific for chromosomes 13, 18, 21, X and Y in the control group (n= 5), the ISOA (n= 10) and the URM (n= 12).

RESULTSPatients with ISOA and URM showed a significantly higher abnormality with total rate of 4.02% (n= 19) and 3.91%(n= 38) for chromosomes 13, 18 and 21, and 2.03%, 1.98% for chromosomes X and Y, respectively, in their spermatozoa compared to control (1.29% and 0.61%, P< 0.01). A significantly higher proportion of total sperm DNA fragmentation was detected in patients with ISOA (40.7%+/- 17.8%) and URM (22.1%+/- 10.3%) of sperm compared to the control group (12.1%+/- 5.2%, P< 0.01). Moreover, a positive correlation was found between the rate of sperm chromosomal aberration and the rate of sperm DNA fragmentation (gamma = 0.874, P< 0.01, n= 27). There were significant correlation between sperm DNA fragmentation and sperm density, sperm motility and abnormal sperm (gamma = - 0.571, gamma = - 0.616 and gamma = 0.637, respectively, P< 0.01).

CONCLUSIONThe result indicates that spermatozoa from patients with ISOA and URM contain greater DNA fragmentation and chromosomal aneuploidy and may lead to male infertility. Screening for sperm DNA damage may provide useful information in the diagnosis of male idiopathic infertility.