Cryopreservation (sperm, oocytes and embryos)

Cryopreservation is a process of long-term storage of cells and tissues in a specialized facility (cryobank) at extremely low temperatures (down to −196°C) with the use of liquid nitrogen. Under these conditions, all biochemical processes within cells are halted, allowing biological material to be preserved for many years without loss of quality or viability. The main objects of cryopreservation in reproductive medicine are:

• Spermatozoa
• Oocytes (eggs)
• Embryos

Cryopreservation is widely used in in vitro fertilization (IVF) programs and other assisted reproductive technologies (ART).

Sperm cryopreservation in Belarus

Sperm freezing is one of the earliest and most well-developed procedures in reproductive medicine. The sperm freezing process includes:

1. Semen collection.
2. Addition of cryoprotectants, which protect cells from damage during freezing.
3. Freezing of spermatozoa in liquid nitrogen at a temperature of −196°C.

Who may need sperm cryopreservation:

• Men undergoing cancer treatment (chemotherapy and radiotherapy may affect fertility);
• Patients scheduled for surgery on the reproductive organs;
• Men wishing to postpone fatherhood for personal or professional reasons;
• Couples participating in IVF procedures where sperm preservation is required for future use.

Oocyte cryopreservation in Belarus

Egg freezing is becoming increasingly popular among women. This procedure is often used in cases where, for medical reasons or personal circumstances, a woman needs to postpone pregnancy.

Main stages of the procedure:

1. Hormonal ovarian stimulation (the physician prescribes hormonal medications to stimulate the ovaries to produce several oocytes in a single cycle).
2. Oocyte retrieval (after stimulation, ovarian puncture is performed under ultrasound guidance, during which mature oocytes are collected).
3. Egg freezing (the retrieved oocytes are treated with special cryoprotectants and rapidly frozen using the vitrification method, which prevents the formation of ice crystals that could damage the cells).

Who may need oocyte cryopreservation:

• Women diagnosed with cancer (chemotherapy and radiotherapy may lead to infertility; freezing eggs before treatment helps preserve fertility).
• Women over 30 who wish to postpone pregnancy (female fertility declines with age, especially after 35 years; freezing oocytes at a younger age allows their use in the future when a woman is ready for motherhood).
• IVF programs (if, for certain reasons, oocytes cannot be used immediately for fertilization, they can be frozen and stored until an appropriate time).

Embryo cryopreservation in Belarus

Embryo cryopreservation is the freezing of fertilized eggs obtained during IVF. This method is often used to preserve “surplus” embryos after a successful IVF procedure or when embryo transfer into the uterus needs to be postponed.

Stages of embryo cryopreservation:

1. Fertilization of oocytes (after retrieval, oocytes are fertilized with spermatozoa in the laboratory. On day 3 or day 5 after fertilization, embryos are assessed according to quality criteria).
2. Selection of embryos for freezing (fertilized embryos of good quality may be frozen for later use. This is especially useful for women who cannot undergo repeated IVF cycles).
3. Freezing of embryos.

Advantages of embryo cryopreservation:

• Increased chances of pregnancy (the possibility of using multiple embryos in the future increases the likelihood of successful implantation).
• Reduced physical burden (after a successful IVF cycle, there is no need to repeat ovarian stimulation and puncture — frozen embryos can be used).
• Postponement of pregnancy (frozen embryos can be stored for many years, allowing women to plan pregnancy at the most convenient time in their lives).

According to the regulatory acts of the Republic of Belarus, the maximum storage period for cryopreserved germ cells is 10 years. This period is established to protect the quality and viability of biological material and to ensure control over long-term storage of genetic material.

Cryopreservation in Belarus is an effective way to preserve reproductive health for men and women facing medical challenges or wishing to postpone childbirth. Thanks to modern technologies and the availability of medical services, this procedure is becoming increasingly in demand. Cryopreservation is not only a means of preserving reproductive potential but also a way to plan life, with possible medical and social changes taken into account. Of great importance is to seek specialist consultation in a timely manner in order to make the right decision at the appropriate moment.