The guideline values of the WHO (World Health Organisation) for the year 2010 establish as the normal base limit for the volume of a sperm sample > 1.5ml.

Sperm capacitation involves the physiological changes that are produced naturally in the spermatozoa as they swim up the female genital tract and which enable them to acquire the capacity to fertilise. These modifications are: The change in the way in which the spermatozoide moves, changing from moving in a straight line to oscillating. The modification in the composition of the outer part of the spermatozoide, known as the membrane, to acquire the capacity to fuse with the egg.

Assisted reproduction is increasingly in demand, and the most important reason is the delay in the age of women having her first child. The average age of first birth in 1975 was at 28 years and currently is at 32.