To assess motility and estimate sperm concentration, switch to 400X magnification. An estimate of sperm concentration may be needed to determine an appropriate dilution for performance of the sperm count. Non-spermatozoa cells, such as epithelial cells (derived from the urogenital tract) and round cells, which include leukocytes and spermatids, can be observed using 400X magnification. However, identification and differentiation of leukocytes and spermatids should not be attempted on an unstained wet preparation. These cells can be more accurately identified through the use of PAP- or Wright-stained smears.
A phase contrast microscope is recommended for wet mount examination of semen.