Sperm cleanup and centrifugation processing for cryopreservation.

Fertility rates with artificial insemination are highest with good-quality sperm samples. Therefore, nonviable sperm, cellular debris, and seminal plasma are preferably removed from semen samples prior to use or for preservation. Such compounds are sources where reactive oxygen species are generated during storage or upon cryopreservation, impairing sperm function. In this chapter we describe methods to remove seminal plasma and cellular debris from sperm samples, and for selecting morphologically normal motile sperm. The methods that are described here include: ordinary centrifugation, sperm swim-up, glass wool and Sephadex filtration/adherence, and single-layer as well as discontinuous two-layer iodixanol density gradient centrifugation.