Sperm processing

After semen is collected, it can be processed to yield healthy sperm that are suitable for insemination by IUI or IVF. There are several methods of sperm processing, each with its own approach:

1. Density Gradient Centrifugation: This method involves layering semen in a tube with different densities of a viscous solution and then centrifuging it. The process separates sperm based on their motility and density. Healthier, more motile sperm cells migrate to the bottom of the tube, separating them from less viable sperm and other cellular debris.
2. Swim-up Technique: In this technique, a small amount of semen is placed beneath a layer of culture medium and left to incubate. The most motile sperm cells “swim up” into the medium over time. These upward-moving sperm are then collected from the top layer, ensuring that the selected sperm are highly motile and more likely to fertilize an egg.
3. Microfluidics: This modern technique uses a micro-channel device to separate sperm without the need for centrifugation. Sperm are passed through microscopic channels that mimic the female reproductive tract, selecting sperm based on their ability to swim effectively through these channels. This method is gentler and thought to reduce damage to the sperm DNA (sperm DNA fragmentation), potentially leading to better fertilization outcomes and healthier embryos. An example of a microfluidics device is Zymot.