When artificial insemination techniques are used to help a woman conceive a child, fertility clinics and sperm banks sometimes use sperm washing as part of the process. This step is used to separate the sperm that will be used for the procedure from the semen sample a man provides. Doctors also use sperm washing to get rid of any protective fluid in which the sperm may rest while it is stored prior to washing. While some artificial insemination techniques do not require sperm washing, it is considered important for a procedure referred to as intrauterine insemination (IUI), because using unwashed sperm in this case can cause irritation and infection. Sperm washing also can help ensure that a sample contains the most motile sperm, or those with the strongest, swiftest movement.
Sperm washing is a procedure used to prepare sperm for use in artificial insemination, specifically IUI. With this procedure, fertility clinics separate sperm that are needed to fertilize an egg from the semen and any protective fluid in which they are contained. Sperm banks sometimes also perform this procedure to prepare sperm for use by fertility clinics and individuals who will perform IUI at home, without the help of a doctor. Sperm banks typically offer individuals the option of buying washed or unwashed sperm from a sperm bank. If a person is undergoing artificial insemination with the sperm inserted into the vagina or cervix, sperm washing isn’t usually necessary.
The washing technique used sometimes involves the addition of protein and antibiotics to the semen sample. Then, using a gradual process, the sperm are removed from the semen and any protective fluid in which they were originally placed. This process does not involve choosing the sperm that have the best movement.
In some cases, doctors and artificial insemination recipients may decide to choose more than just a basic wash. In such a case, the technique incorporates the purification of the sperm in the sample and the removal of only the most motile sperm. This is usually accomplished by creating a layer of fluid into which only the best sperm can swim. These highly motile sperm are then used for artificial insemination and the rest are discarded. Processes that involve isolating only the best sperm and washing it requires more time than regular washing, but all of these procedures usually take only a couple of hours to complete.