Sperm motility is important because sperm must be moving in order to penetrate the cervical mucus, travel to the fallopian tube, and fertilize ova.
Accurate motility evaluation requires standardization of temperature, sample size, and depth of chamber for viewing. Some laboratories read motility at 37°C while others routinely report motility at room temperature. The temperature of the assessment should be specified in the final report and all laboratory personnel must perform the analysis at the temperature stated in the laboratory's procedure.
The laboratory's procedure should also state the volume of semen to be used for viewing motility, eg, 10 mL. The coverslip that is used for the stated semen volume should provide a chamber approximately 20 µm in depth. A chamber depth that is less than 20 µm may constrict the movement of sperm and a chamber that is too deep will not display the spermatozoa in a single plane, making it difficult to assess motility.
The use of an eyepiece reticle with grid, as shown in the image on the right, is recommended for more accurate assessment within a defined area of the microscopic field. If the sperm concentration is high, score only the top row of the grid. If the concentration is low, score the entire grid. Do NOT choose fields to view based on observation of highest motility. This will cause inaccurate results to be reported.