what is sperm washing

Sperm washing is a process in which individual sperms are separated from the semen to improve the chances of fertilization and to extract certain disease-carrying material in the semen. The washed sperm is used in artificial insemination using the intrauterine insemination (IUI) technique and in in vitro fertilization (IVF) . Sperm washing involves removing any mucus and non-motile sperm in the semen to improve the chances of fertilization and to extract certain disease-carrying material in the semen. The process of sperm washing takes place in a laboratory following sperm donation and can be done by density gradient centrifugation or by a "direct swim-up" technique that does not involve centrifugation. The washed sperm is concentrated in a special sperm media or solution called HTF (Human Tubal Fluid) which nourishes and preserves them for fertilization of the egg. Sperm washing also removes materials from the semen specimen that may impair fertility, such as bacteria and hormones. Sperm washing can be used to decrease the risk of HIV transmission in HIV-positive males, because the infection is carried in the seminal fluid. Techniques used for sperm washing include basic sperm wash, density gradient sperm wash, and swim-up technique.