Cryopreservation is the term used to describe the process of freezing and storing sperm, eggs or surplus embryos from an in vitro fertilization cycle.
There are 2 methods currently used for freezing in IVF labs-slow freezing and vitrification (ultra-rapid freezing)
Vitrification is the process of converting something into a solid without any crystal formation. This is done by adding a cryo-protectant. This is important because ice crystal formation can be very damaging to frozen embryos.
Embryos can be frozen at the pronuclear stage (one cell), or at any stage after that up to and including the blastocyst stage (5-7 days after fertilization). Different cryoprotectants and freezing solutions and protocols are used for different stages of embryo development. Many IVF clinics freeze their embryos at the blastocyst stage
Sperm Freezing
Sperm freezing also known as cryopreservation or semen banking is a technique of preserving sperm by freezing and storing it in liquid nitrogen at the temperature of -196⁰C that is used on a later date for fertilizing an egg.
Sperm freezing is useful if:
- you have a condition or are facing medical treatment for a condition, that may affect your fertility
- you are about to have a vasectomy
- you have a low sperm count or the quality of your sperm is deteriorating
- you have difficulty producing a sample on the day of fertility treatment
- you are at risk of injury or death (eg: you’re a member of the Armed Forces who is being deployed to a war zone)
Procedure before you store sperm
- You need to go through careful screening for HIV, HBV, HCV, etc. to avoid chances of infection.
- You need to give written consent regarding what will happen to your sperm if you cannot make decisions for yourself or die, whether anybody can use your sperm such as your partner or for research or if it can be donated for somebody else’s treatment and for how long you want to store your sperm
The standard time for storing sperm is 10 years, but you can extend the storage time up to 55 years. Before doing that your Andrologist will check the condition of the sperm in one of the vials and helps you decide on the fate of the frozen sperms.
Cryopreservation is a method that freezes and preserves sperm, eggs, or embryos. It is mostly applied in IVF to conserve fertility for future use by individuals who wish to postpone childbearing. This ensures that the eggs or sperm are maintained viable for eventual fertilization. This process is very efficient since it decreases the risk of infertility caused by ageing or health complications.
There is also a freezing stage to pronuclear when the embryo has just one cell. The later stage at which freezing can happen includes any day up and until the blastocyst, usually around 5 to 7 days after conception. This stage is often preferred by those in vitro since the blastocyst will have better chances during the thawing process due to being developed more, hence increasing its chances of surviving thawing. However, freezing depends solely on the quality and readiness of the embryo.
Sperm freezing, also known as semen banking, is a method that freezes sperm at extremely low temperatures, specifically -196°C, using liquid nitrogen, with the potential to be kept for use in fertilizing an egg in the future. Most individuals go for this when they are expected to undergo any medical treatment which can affect fertility, such as chemotherapy and radiation therapy, or have personal reasons for delaying a family. It gives people the possibility of preserving fertility in case of unexpected changes.
Before sperm can be banked, a series of tests need to be done to ensure the sperm is disease-free and will not transfer disease when fertility treatments are implemented. These tests commonly include HIV, HBV (Hepatitis B virus), HCV (Hepatitis C virus), and other sexually transmitted infections. The aim is to make the sperm safe for later use so that there is less of a chance of transmitting health risks to the partner and the child.
For sperm to be stored, there should be written consent. This shows specific instructions concerning the sperm's use. This consent indicates what will be done with your sperm in case you can no longer decide on some issues in future. Whether the sperm will be donated to others or used in IVF for your partner will also be determined. The consent process ensures that your wishes are followed and that all legal and ethical considerations are addressed.
Under standard guidelines, the sperm can be stored for up to 10 years, but depending on individual circumstances, the period may vary. However, in some cases, with the advice of an Andrologist, sperm storage can be extended up to 55 years. The period of storage depends on the condition of the sperm and how it survives the freezing and thawing process. A fertility doctor will be consulted to determine how best to proceed based on the quality and condition of the sperm.
