Semen preservation is a relatively simple procedure and it typically involves collecting and then freezing a sample of semen taken from a male donor. This sperm can be used by the donor later to impregnate his partner, or it may be donated to a woman or couple looking to become pregnant through artificial insemination. Despite great advances in technology regarding fertility treatments, cryopreservation is still the primary option for semen preservation.
When a male ejaculates, a white or clear fluid is ejected from the urethra in the penis. This fluid contains millions of tiny living cells called sperm. These sperm can meet with an ovulated egg for fertilization to occur. Sperm still inside the semen can be preserved for later use in males who have concerns about future fertility, or who want to donate their sperm to be used by another couple or individual.
The process for semen preservation is relatively simple. A male will typically have his semen evaluated before giving a sample for storage. This is done by having the man enter a private room where he will be asked to ejaculate into a sterile cup. This cup is then labeled, and the semen is allowed to liquefy over the course of about half an hour. Once this has occurred, the semen will be inspected under a microscope to check for sperm motility, sperm count, and other factors that are important in terms of a man's fertility.
This testing is generally performed prior to semen preservation, because the sperm quality may affect the number of samples that will need to be frozen for successful fertilization. The process of collection is the same as for a sperm evaluation, only this time the specimen is kept inside the container and frozen in liquid nitrogen. Some sperm will die during the freezing process, but many will remain intact until they are needed.
Since sperm are destroyed during semen preservation, it is recommended that males undergoing this process abstain from ejaculation for at least three or more days prior to giving their samples. This will ensure a high sperm concentration in each ejaculation. Those with low sperm count or low sperm motility may need to provide more samples for successful insemination, although even smaller numbers of sperm are sufficient for many new infertility treatments.