Semen freezing is a routine procedure that has been available throughout Australia and the world for many years and is used to preserve sperm cells. All semen freezing mediums will use a cryoprotectant agent (such as glycerol) to protect the cells and gentamicin as an antibiotic. For the slow freezing method, the cryoprotectant is added in equal volumes in a drop wise manner before gradually decreasing the temperature until it can be frozen and stored in liquid nitrogen at -196 degrees Celsius.
Semen freezing is useful and recommended for both fertility preservation and fertility treatment.
Who May Benefit From Semen Freezing?
Men who are faced with the following, may find sperm freezing suitable for them:
- Prior to chemotherapy treatment, as this may render a male infertile
- Prior to a vasectomy, as this will mean that if later in life the male wishes to father another child, he may not have to proceed with either a vasectomy reversal or surgical methods to retrieve sperm to fertilise an egg
- Pre-surgery involving the male reproductive tract and/or testicles
- Ejaculatory problems or dysfunction, to minimise the anxiety of producing a sample for fertility treatment in subsequent treatment cycles
- Absence of the male partner (e.g. due to work commitments) during a fertility treatment cycle
- It may also be considered for men in high risk occupations (e.g. defence force)
The use of semen freezing therefore makes it possible for men to preserve their fertility or undergo life saving medical treatment, with the chance of future fertility success. There is also mounting evidence that semen quality is reduced in men from the age of 40 and as such, it may be considered useful to freeze semen early in a man’s reproductive life. However it is important to consider the effects of freezing, which may make a sample unsuitable for certain types of treatment (see effects of freezing in a later section).
Donor semen (clinic recruited or known donor) is also frozen and used in subsequent treatment cycles. These samples need to be quarantined for a minimum of 6 months to ensure that the semen is free from infectious diseases prior to treatment. If you are interested in becoming a donor please contact the Fertility Solutions Donor Co-ordinator.
How Is Sperm Collected?
Usually fresh sperm is collected by either masturbation or surgical methods (e.g. MESA – micro-epidydimal sperm aspiration or TESE – testicular sperm extraction). If collection is via masturbation, the male should abstain from sexual activity for between 2-5 days and produce the sample into a sterile container. Ideally the sample would be produced at our clinic so that it can start to be processed immediately after collection.
A surgically retrieved sperm sample will be collected with either a fertility specialist under a local anesthetic, or with an urologist under a general anesthetic. If a general anesthetic is necessary, additional hospital fees will be required to be paid prior to the day of surgery.
What Happens Prior To Freezing?
After collection, the sample undergoes a complete semen analysis. This is to examine a number of important parameters including semen volume, sperm concentration, sperm motility and sperm morphology. The results of this testing will allow us to make a recommendation for future use of the frozen sample and these will be sent to your referring doctor within 3 working days.
Sperm Concentration: is a measurement of the density or number of sperm in the sample. It is usually reported as a value per millilitre and the normal value is greater than 15 million/mL. A reduced number of sperm present in a sample is referred to as oligospermia. In the event that no sperm are present in the sample, it is referred to as azoospermia.
Sperm Motility: refers to the movement of the sperm, especially forward progression, and is reported as a percentage. The movement of sperm is divided into three (3) categories:
- Progressive motility (PR), which refers to sperm moving actively, either linearly or in a large circle regardless of speed
- Non-progressive motility (NP), which refers to sperm which are not moving in a forward motion (i.e. absence of progression)
- Immotile, which refers to sperm that show no movement. Sperm which do not show movement may in fact be dead and therefore not capable of fertilising an oocyte.
If a sample shows reduced numbers of motile sperm it is referred to as asthenozoospermia.
Sperm Morphology: is a visual assessment of the shape of the sperm. This is reported as a percentage and the normal value is greater than 4%. A reduced number of normal appearing sperm is referred to as teratozoospermia.
What Do I Need To Do To Arrange A Semen Freeze?
- Obtain a referral from either a GP or your specialist. It is also recommended that if you have not been tested for infectious diseases recently, that a referral to a suitable pathology centre is also obtained for HIV, Hep B, Hep C, chlamydia, cytomegalovirus and syphilis prior to freezing.
- Phone Fertility Solutions to arrange a semen freeze appointment. At this appointment it will be necessary to sign relevant consents and have a discussion with a Scientist about the freezing process prior to providing a sample for freezing.
- Upon providing a sample for freezing, a Semen Declaration Form is required to be completed and signed by the patient providing the sample.
- Subsequent semen freezing appointments may be necessary depending on the quality and quantity of the initial sample provided.
Are Sperm Parameters Affected During Semen Freezing?
Sperm concentration and motility is expected to be affected during the freezing process. This is because a cryoprotectant needs to be added to the semen at a ratio of 1:1 and unfortunately not all the sperm will survive the freezing and thawing process. Therefore if we consider a sample which initially is 50 million/mL prior to freezing, once the cryoprotectant is added this will reduce the sample concentration to approximately 25 million/mL.
Similarly, not all motile sperm will survive the process; in fact it is common that only somewhere between 25%-50% of motile sperm survive freezing and thawing. Therefore this too can impact what type of treatment the frozen sperm will be recommended for. It is suggested that if you have frozen sperm, to follow up with your specialist prior to proceeding with a cycle, to ensure that the sample is suitable for your planned treatment.
How Long Can The Sample Be Frozen For?
Semen can be stored indefinitely once frozen, however there are guidelines which recommend that samples are stored for a maximum of ten years.
What Are The Fees Associated With Freezing?
There will be an initial fee associated with the semen analysis and freeze cost. There may be additional costs for subsequent samples that are frozen, however this will depend on your reason for freezing. There will also be additional six or twelve monthly storage fees. Please contact Fertility Solutions administration staff for the exact fees.
What Can Go Wrong With The Process?
The process of semen freezing is continually being revised and updated. Sometimes things can go wrong. Some of these things are outlined below:
- No sperm are present in the sample provided and as such no sperm is available for subsequent treatment.
- None of the sperm frozen survive the thawing process; this is very uncommon and more likely if the sperm quality was poor at time of production.
- The sample does not prepare as well as initially thought and as such may mean that either additional straws need to be thawed for treatment or another type of treatment is recommended in a subsequent cycle.
- The storage tank/dewar where the semen is stored can malfunction and as such the sample(s) can be lost.
If you would like more information, please phone (07) 5478 2482 and speak with a Scientist.