Abstract

Fresh semen obtained from infertile men occasionally exhibits the total absence of motile sperm (100 asthenozoospermia). Vitality tests may reveal that a proportion of the immotile sperm has functional membranes, which are considered viable. An easy test for the prior determination of sperm viability may assist in sperm selection for the microinjection of oocytes. The main objective of this study was to apply three standard vitality tests on the asthenozoospermia samples from infertile men. A total of 30 semen samples with >50 immotile sperm were obtained for this study. Each semen sample was divided into three equal aliquots following the preliminary evaluation of semen parameters. Three vitality tests of eosin-Y, hypoosmotic swelling (HOS) and pentoxifylline (PX) were applied on all samples. A total of 100 spermatozoa were then evaluated for the sign of viability. The percentage of normal morphology and sperm count were within the normal range of 31.8 ± 15.9 and 55.8 ± 46.6′ 106 per ml., respectively. Following the application of eosin-Y, 45.2 ± 15.2 of spermatozoa were unstained (alive). In addition, 51.9 ± 18.6 and 52.7 ± 21.1 of sperm were observed to be viable with HOS and PX tests, respectively. Three samples with total asthenozoospermia demonstrated with 37.61, 27, and 33.33 viability after the application of eosin-Y, HOS, and PX tests, respectively. The results indicate that the vitality tests are very useful in differentiating live sperm from dead one, even in the samples with total asthenozoospermia. Also, PX may be a more accurate vitality test with a therapeutic application during the microinjection cycles. It not only has the ability to differentiate live sperm, but also enhances motility.