Spermatozoa are made to fertilize eggs. However, spermatozoa are not ready to interact with eggs when ejaculated. They need to undergo a physiological change called capacitation before penetrating the egg.
Capacitation is a temperature dependent phenomenon; variation in the incubation temperature could cause an alteration in some events associated with this process.

Sperm incubation a room temperature produces a temporary blockage of capacitation related events. When maintained under these conditions, cells are in a “quiescent” state (non-capacitated), retaining their functional properties that can be expressed at body temperature of 37°C (1)

The rise in temperature when spermatozoa enter the female reproductive tract could act as a trigger for the activation of spermatozoa, making them hyperactive (Gallup,2009). This hypothesis possibly explains the diminished survival of spermatozoa at 37°C compared with lower temperatures.

Tips and Tricks:

We recommend density gradient to prepare the semen samples and performed at room temperature. Remember, the best is to avoid temperature fluctuation and therefore, the best way to prepare and store the sample, is at room temperature.


Influence of temperature and sperm preparation on the quality of spermatozoa.
Thijssen, Klerkx, Huyser, Bosmans, Campo, Ombelet.
Reprod Biomed Online. 2014 Apr;28(4):436-42. doi: 10.1016/j.rbmo.2013.12.005. Epub 2014 Jan 14.