EVALUATION OF NUCLEAR MATURITY IN HUMAN SPERMATOZOA OBTAINED BY SPERM-PREPARATION METHODS

Change in the nuclear maturity has been considered as an index of sper m quality. This is done by using aniline blue staining that stains spe rmatozoa with disturbances in the chromatin condensation. Therefore, t his technique was used to evaluate the quality of sperm obtained by sp erm preparation methods. In 14 semen samples from healthy donors with normal semen analysis and normal forms, the swim-up (SU), Percoll grad ient centrifugation (PG), glass wool column filtration (GW) and sedime ntation-migration (SM) were performed. GW and SM methods presented the lowest number of spermatozoa with alteration in the nuclear maturity (ANM), 11, 14% and 12, 42% compared to native semen (19%) (P<0.005 and P<0.05 respectively). SU and PG did presented no significant differen ce compared to native semen. In tests using the four methods, approxim ately 60% of the ANM occurred in normal spermatozoa. In the cells with pathologic abnormalities and ANM, 74.5% corresponded to macrocephalic forms, as this abnormality correlated mainly with ANM. It is conclude d that in a semen sample with a higher percentage of normal forms, app roximately 19% will have an ANM. GW and SM methods obtain the lowest p ercentage of ANM. ANM presents itself in 98% of the macrocephalic form s and they are effectively isolated with the PG method. The practice o f this simple technique may orientate towards the sperm preparation me thods to be used in assisted reproduction.