SEMEN PROCESSING
A mandatory step in IVF/ICSI and IUI treatments, semen processing consists of separating sperm cells from the seminal fluid, which contains substances such as prostaglandins (active lipids that act like hormones) that can cause undesirable reactions and intense uterine contractions. In addition, harmful chemical substances and even bacteria may be present in the semen sample. These are also removed to prevent the development of infections.
There are two main semen processing methods:
Discontinuous density gradient
The fastest and most common semen separation method, it consists of applying centrifugal force to the sample, which drives the highest-quality sperm cells to the top and unwanted materials to the bottom of the container. It is the technique that recovers the greatest number of motile sperm cells, but it does not necessarily guarantee the highest motility rate (the ability of sperm cells to move progressively) of the collected gametes.
Swim-up
This method uses sperm motility as the main selection criterion. The best sperm cells detach and swim to the surface, where they are then collected. Since this technique retrieves only about 20% of the total motile sperm cells in the sample, it is not recommended in cases of oligozoospermia (low sperm concentration per mL).
