Optimum Measurement Time for Human Sperm Velocity Determination

The optimal time-duration required by spermatozoa to travel distances from which their average velocity can be accurately determined was investigated. For this purpose, 180 motile spermatozoa, from 12 seminal specimens, were photographed while being illuminated by six light pulses, given at 1-sec intervals. From these photographs, distances traveled by each spermatozoon were measured over identical time periods. Most individual spermatozoa showed slight deviation of their velocity when measured sequentially for 5 sec. Nevertheless, when mean sperm velocity of grouped spermatozoa were determined from 1- or 5-sec measurement time, the results were almost identical. This was attributed to a pure statistical law, that is, the mean deviation decreases as the number of spermatozoa in the sample increases. It was concluded that the sperm velocity of a certain specimen can be determined properly using a 1-sec measurement time. An extended period of time does not seem to contribute to the accuracy of sperm velocity determination.