Oocyte vitrification: what is it?

In recent years, the extracorporealfertilization develops very quickly. This procedure is no longer considered something incredible and inaccessible to ordinary people. IVF is carried out all over the world. Specialized laboratories and clinics are available in every major city. New, improved approaches to fertilization are developed annually. Thanks to the development of this method, many infertile couples were able to become parents. Often, when collecting information about IVF, women are faced with the concept of vitrification of oocytes. This term implies a relatively new procedure, which allows to improve the quality of eggs.

The concept of "oocyte vitrification" - what is it?

To understand how the process happensvitrification, it is necessary to have an idea about in vitro fertilization. This procedure involves the collection of female germ cells (oocytes) from the ovary. Then they are cleaned and fertilized by the partner’s sperm or donor (if the husband cannot have children). After that, the zygote that started to divide is placed in the uterine cavity. Oocyte vitrification is a procedure similar to cryopreservation of eggs. However, it is more refined. By vitrification is meant the freezing of immature germ cells. As a result, oocytes can be saved for a long time. Despite the "frozen" state, vitrified cells remain viable. This procedure is considered a huge breakthrough in medicine, because thanks to her, women have the opportunity to have a child, even in the absence of genital organs.

What is the purpose of oocyte vitrification?

In Europe, concepts likecryopreservation, vitrification of embryos and oocytes, has been known for a long time. This can be judged by Western films on medicine. In the post-Soviet countries, doctors are also familiar with these terms for several decades. However, these procedures have become available to patients recently. In most cases, oocyte vitrification is performed for in vitro fertilization. When carrying out freezing of immature cells in this way, a woman has a greater chance of successful IVF. The first batch of oocytes isolated from the ovary may not settle down. In this case, re-sampling of the material is not required, since there are already vitrified cells. In addition, there are cases when a barren couple asks for the preservation of oocytes for a long time. Often this is required in various pathological conditions in which a woman cannot have children. Also, a similar request is made by patients preparing for surgery to remove the reproductive organs.

What pathologies recommend vitrification of ova?

Vitrification of oocytes and embryos is paidprocedure available to anyone. There are no special indications for it, however, it is necessary only in specific cases. This does not mean that some women cannot afford to vitrify their cells. Nevertheless, in the absence of reasons for freezing oocytes in a similar way, cryopreservation is recommended for patients. Most often, vitrification is carried out in the following conditions:

1. Preparing for oophorectomy. This operation is performed in case of ovarian cancer and suspicion of its development. This reason is not very common, since in most cases, in the oncologic pathology, the uterus is also removed.
2. The inability to obtain sperm on the day of the collection of oocytes. For this reason, cells are required to freeze until fertilization material is provided.
3. Oncological diseases of any localization.Regardless of where the cancer is located, radiation therapy and treatment with chemical (cytostatic) drugs are required. With each of these methods of exposure, pregnancy is undesirable. After all, similar methods of treatment destroy not only cancer cells, but also healthy cells, including oocytes.
4. The desire of a woman to have children in a remote period,for example, after menopause. In such cases, cryopreservation is rarely productive, since eggs with this method of freezing are viable for a short time. Therefore, doctors propose an alternative method - oocyte vitrification.
5. Repeated IVF, if for the first time the eggs do not survive. In this case, they offer vitrification in order not to take the material three times.

Stimulated donor oocytes - what is it?

In some cases, a barren couple does not haveopportunities to conceive a child even with the help of in vitro fertilization. We are talking about women with dysfunction of the sex glands. To this end, donor oocyte banks have been developed. Unfortunately, they are not available in all countries. All immature germ cells are vitrified, so they can be stored. The indications for IVF using donor oocytes are:

1. Genetically determined pathology - ovarian exhaustion syndrome.
2. The absence of oocytes due to the age characteristics of the reproductive system (from 40 years and older).
3. The inability to stimulate ovulation due to surgical interventions on the ovaries, the effects of chemotherapy.
4. The risk of having a child with a genetic pathology.
5. Repeated IVF, which did not produce a result due to the “poor quality” of own eggs.

Who can donate vitrified oocytes: requirements

Family planning is a very serious decision.This is especially true when the couple is forced to use donor cells. Before getting the oocytes and subjecting them to vitrification, doctors conduct many examinations of both the woman and the material provided. One of the conditions established in the bank of frozen eggs is anonymity. That is, future parents should not know about the donor, and vice versa. Requirements for women who decided to vitrify their oocytes:

1. Age: 20-35 years old.
2. Lack of somatic and genetic diseases.
3. Mild phenotype.
4. The presence of the donor at least one of their own child.
5. Consent to confidentiality.

Technique of vitrification

Before you start to freeze femalegerm cells, ovulation is stimulated. It is necessary that there are several oocytes, not just one. After all, normally, when ovulation occurs, only 1 ovule matures and leaves the follicle. Stimulation is carried out with medication. Next is an ultrasound of the pelvic organs. If it turned out that ovulation has taken place and there are sufficient oocytes in the ovary, then the IVF procedure is continued. Cell sampling is performed under anesthesia. To get the puncture needle exactly where the oocytes are located, the whole procedure is performed under the control of an ultrasound. After taking the material proceed to the next stage - the preservation of immature eggs. Oocyte vitrification in the natural cycle is performed due to the method of rapid freezing. This is the main feature of this method of conservation.

Benefits of egg vitrification

Considering that the vitrification process begangradually replacing other methods of preserving eggs and embryos, it is preferable not only in the opinion of doctors, but also for patients. This method has the following advantages:

1. Ability to postpone pregnancy. Due to the fact that oocytes and embryos are frozen for a long time (depending on the decision of the woman).
2. The ability to repeat the IVF procedure without taking the material a second (or more) time.
3. Ability to conceive after surgery on the gonads, radiation and chemotherapy.

What is the difference between vitrification and cryopreservation of eggs?

Как известно, процессы криокенсервации и vitrification of ova is very similar. Both methods are designed to freeze oocytes and embryos in order to preserve their viability. However, there are some differences. Often, during cryopreservation, immature eggs are damaged. This is due to the fact that this method implies slow freezing of the material. As a result, the liquid cytoplasm turns into ice crystals. It is they that damage the cell wall. A method other than cryopreservation is vitrification of oocytes. The percentage of defrost when it is held is much lower, as the cooling of the eggs occurs almost instantly. That is, the main difference from cryopreservation is considered to be new technologies that allow long-term preservation of oocytes in a viable state. Delay conception for a long time can only be a method of vitrification. Cryopreservation does not give such long results.

How is IVF performed after oocyte vitrification?

Витрификация ооцитов проводится не везде.Freezing germ cells and embryos for a long time engaged only in highly specialized laboratories. Almost at every clinic with this equipment there is a bank of donor vitrified oocytes. After a woman makes a decision about wanting to conceive a child, the cells are thawed. Fertilization is then performed using the ICSI method. The resulting embryo is cultivated (3-5 days), and implanted into a pre-prepared endometrium. The remaining fertilized cells can be vitrified again. If the implantation attempt is unsuccessful, the IVF procedure is repeated.

Oocyte vitrification: doctor reviews

Currently, oocyte vitrification and storageand embryos are performed in all major cities with advanced medicine. After this method was tested and established itself, doctors respond positively to it, assessing the advantages over other (early) egg storage procedures. Many women can allow themselves to freeze their own oocytes. The cost of the procedure is about 12 thousand rubles. This is the price for vitrification. The cost of storing frozen cells is 1 thousand rubles per month.