Sperm Freezing

Medical Fertility Preservation for Men

If you need to have treatment for cancer that may affect your fertility, there are options available to ensure you can still have children in the future.

Chemotherapy and radiotherapy can affect your sperm production – sometimes this is temporary but in other cases it may be permanent. Once your treatment begins, it may be too late to collect and preserve your sperm as it may already carry genetic damage. So, we strongly recommend you contact our Andrology Unit before commencing any cancer treatment.

Freezing sperm

Before you begin chemotherapy or radiotherapy treatment, some of your semen, containing sperm, can be frozen and kept until you wish to start a family.

Men who have to travel overseas or not present on day of their wife oocyte retrieval procedure may also want to have their sperm frozen for use in the future.

  • How fertility preservation is done?

    Men: Sperm Freezing

    General: Before you proceed with freezing and storing your sperms, one of our consultants will see you and explain what the process involves, listing any possible risks, especially for patients that will undergo anti-cancer treatment (for instance, chemotherapy and / or radiotherapy). We advise collection of sperm prior any such treatment, as side effects on sperm’s genetic material may appear as early as the first dosage.

    We also ask for a health screen to rule out infectious diseases or other medical conditions.

    Procedure: Depending on your individual circumstances for the freezing, you may be required to come to the clinic 2-4 times for the production of a fresh sample. After production in a private room in our Andrology unit, the semen is collected immediately before its quality declines.

    In the laboratory, our embryologists first wash the semen samples removing excess of material and isolating the sperms. Then, they perform a quick analysis of the sperm quality and mix it with a cryoprotective liquid. Following, it is either gradually cooled in liquid-nitrogen vapor, or rapidly cooled in liquid nitrogen, by a method called vitrification.

    Typically, 2-8 straws (ampules of samples), are produced per ejaculate, although this may vary depending on individual circumstances, sperm quality and quantity. These are stored in vessels containing liquid nitrogen for up to 5 years.

    If you are unable to produce enough sperm in the semen, we may be able to isolate sperm directly from your testicles using a needle. This procedure, also known as Percutaneous Sperm Aspiration (PESA), is performed by an experienced gynecologist or urologist, under local anesthesia, and involves minimal risk. The recovered sperm can be frozen in the same way as sperms coming from the ejaculate, and later can be used for fertilization with ICSI.

    In some cases, a testicular biopsy may be needed (please see Testicular Sperm Recovery Methods).

    Usage: Once, you decide to use your stored sperms, your options will depend on the quality and the amount of your stored sample, as well as your wife’s fertility. Sperms are thawed to normal temperature through a carefully controlled process. As these samples are very valuable, we always recommend using the minimum amount necessary to fertilize the available eggs through the ICSI procedure. With this approach, a few straws of frozen sperm can be enough for having several children.

  • How successful can sperm freezing be?

    Freezing of sperm cells has been routinely performed for the last 40 years, leading to a high number of live births.

    Although it is a highly efficient procedure, not all sperm cells survive. A range of about 25-60% of the sperm is recovered after freezing and thawing. Success rates also depend on maternal age and quality of eggs.