If you are going for IUI then you will need to order washed sperm unless your individual clinic has facilities to wash the sperm for you.
'Washed' sperm means the sperm is separated from the semen.
Washing or spinning the sperm is a laboratory technique for separating sperm from semen and separating non-motile sperm from motile sperm.
The ejaculate is mixed with a washing medium followed by centrifugation (spun at high speed). The sperm rich fraction left at the end of this spinning process is mixed with more washing medium and the process repeated 2-3 times until only the highest quality sperm remain. This is then placed into a test tube ready for insemination.
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