Why is the Microcell 20 microns deep?
20 microns allows the visualization of all sperm in a single plane for counting accuracy while not constricting the movement of the sperm allowing for a more accurate motility assessment. “The volume of semen and the dimensions of the cover slip must be standardized so that the analyses are always carried out in a preparation of a fixed depth of about 20 micrometers. This allows a rough estimate of sperm concentration to be made in order to determine how to prepare the semen for accurate determination of sperm concentration. Depths less than 20 microns may constrain the rotational movement of the spermatozoa.” – 1999 Edition WHO manual Chapter 2, Section 2.4.
