Hyperactivated motility of human spermatozoa: a review of physiological function and application in assisted reproduction.

Hyperactivated motility is a specific movement pattern which has been recognized in mammalian spermatozoa for over 25 years. During this time, it has been established that hyperactivation is part of the complex process of sperm capacitation, which is necessary before fertilization can occur. The recent introduction of computed sperm motility analysis has allowed detailed studies of sperm movement characteristics to be undertaken, and evidence is accumulating that hyperactivated motility may correlate with fertility. In this review, the physiological consequences of hyperactivated motility, methods of measurement and their application in assisted reproduction are discussed.