Parameter | Definition | Unit |
Total Motility (TM) | Percent of sperm showing any movement | % |
Progressive Motility (PM) | Percent of sperm moving rapidly and in a straight path | % |
Rapid Motility (RAP) | Percent of sperm travelling at a speed of 25 µm/sec or faster | % |
Curvilinear Velocity (VCL) | Time-average velocity of sperm head along its actual path | µm/s |
Straight Line Velocity (VSL) | Time-average velocity of sperm head projected along straight line | µm/s |
Average Path Velocity (VAP) | Time-average velocity of sperm head projected along its spatial trajectory | µm/s |
Linearity (LIN) | Ratio of projected length to total length of curvilinear trajectory; LIN = VSL/VCL | % |
Straightness (STR) | Ratio of projected length to average velocity of sperm head along a spatial trajectory, STR = VSL/VAP | % |
Wobble (WOB) | Expression of the degree of oscillation of the curvilinear path about its spatial average path; WOB = VAP/VCL | % |