Immature sperm and leukocytes (collectively known as round cells) must not be included in the count; they can be counted separately or counted during the morphology examination.
When a hemocytometer is used, the count must be performed in duplicate, counting both sides of the hemocytometer. The duplicate counts must agree within the laboratory’s defined limits of agreement. A sufficient number of spermatozoa (at least 200/side) should be counted to achieve a low sampling error.
Counting chambers are available that are designed specifically for sperm counting. These chambers may not require dilution of the specimen and may not require duplicate counts.