To assess motility and estimate sperm concentration, switch to 400× magnification. An estimate of sperm concentration may be needed to determine an appropriate dilution for the performance of the sperm count. Non-spermatozoa cells, such as epithelial cells (derived from the urogenital tract) and round cells, including leukocytes and spermatids, can be observed using 400× 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 using PAP- or Wright-stained smears.
A phase-contrast microscope is recommended for wet mount examination of semen.
