Sperm aspiration involve a simple aspiration(processing of sperms) for men who have a blockage or require much more extensive sampling of the testis for males who have a sperm production problem. As a result, there is a significant difference in the amount of time it takes, time depend on various health factors. Need for anesthesia and the equipment utilized are all the important key factors.

Very few tests allow for an accurate prediction or a 100% effective result of whether or not sperm will be found in the testes of men with any testicular problems. Genetic testing may give insight into the chance of finding sperm but are not absolutely correct. But again there is no appropriate result that absolutely predicts the presence or absence of sperm. Other blood tests, including hormonal studies, are also not predictive most of the times.