Patients with low testicular volume have worse biofunctional sperm parameters

Background/Aim: Lower testicular volume (TV) (<12 cm3) is associated with lower testicular function. Several studies have examined the conventional sperm parameters (concentration, motility, and morphology) and the endocrine function (gonadotropins and testosterone serum levels) in the patients with reduction of TV. No other parameters have been examined. The aim of this study was to evaluate some biofunctional sperm parameters by flow cytometry of men with reduced TV compared with that of subjects with normal TV. Subjects and Methods: 78 patients without primary scrotal disease were submitted to ultrasound evaluation of the testis. They were divided into two groups according to testicular volume, calculated by the ellipsoid formula (length x width x thickness x 0.52): All patients underwent blood sampling for hormone measurements and evaluation of conventional and biofunctional (by flow cytometry) sperm parameters evaluation. Results: As expected, TV correlated positively with the following conventional sperm parameters: semen volume, sperm concentration, progressive motility, and normal forms (p<0.001) and negatively with the percentage of spermatids (p<0.001). No statistically significant correlation was found with pH. LH, FSH, and E2 serum concentration correlated negatively with testicular volume, while no statistically significant correlation was found with T and prolactin. The following biofunctional sperm parameters mitochondrial membrane potential, phosphatidylserine externalization, chromatin compactness, and DNA fragmentation) correlated strongly negatively with TV (p<0.0001). Conclusions: This study confirmed that conventional sperm parameters and serum hormone are worst in patients with low TV, whereas it, for the first time, showed that patients with low TV have impaired sperm mithocondrial function, early apoptosis, and abnormal chromatin/DNA integrity.