Sperm capacitation is the process by which the sperm acquires the ability to fertilize the egg. In a natural relationship, it occurs after ejaculation, when sperm enter the female reproductive system. While in the laboratory we force this capacitation by means of some processes of sperm washing in which, in addition, we select the best ones, eliminating the immobile ones and the substances that can be toxic for the spermatozoid.
In the laboratory, the duration of this process is between 30-60 minutes, depending on the type of training we select. We can choose between:
- Density gradients: where we separate and concentrate by centrifugation. In this training we select those spermatozoids that manage to cross the gradients. It takes about 30 minutes.
- Swim-up: where we also centrifuge the sample to concentrate it and eliminate the supernatant (seminal plasma). We add a new medium and it will be in this new medium where we will select the spermatozoa that have managed to rise or "swim" after 40 minutes in the incubator.
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