Andrology

Semen processing protocols vary depending on the specific assisted reproductive technology (ART) procedure being used, as well as the quality of the spermatozoa—factors such as concentration, motility, viability and morphology. The primary goal of these protocols is to enhance spermatozoa selection by isolating the most motile and morphologically normal, while removing debris, non-viable spermatozoa, and seminal plasma. This results in a concentrated spermatozoa sample optimized for the intended ART technique.

Below are the core semen processing methods described in the WHO Laboratory Manual for the Examination and Processing of Human Semen, 6th Edition (2021), each tailored to specific semen parameters and ART applications:

1. Swim-up
2. Simple washing
3. Discontinuous density gradient 
4. Magnetic-Activated Cell Sorting (MACS)