In the daily hustle and bustle, in pursuit of a good education, brilliant career, financial solvency, many women forget that their reproductive capacity is limited. The number of eggs a girl is born with decreases every month. And along with this, the chances of motherhood decrease. One of the ways to prolong your "female" time is to cryopreservation of eggs. About what methods of freezing oocytes exist, what are their advantages and disadvantages, and which one to choose, we will tell in this material.
What it is?
Freezing of eggs has been practiced in the world for a long time. Experiments with freezing female germ cells first began in 1986 in Canada, but the task turned out to be almost unbearable - it was possible to freeze oocytes, but not to preserve their functions after thawing.
In the USSR, they thought about cryopreservation of germ cells in the 80s of the last century, they began to experiment, in 2010 in Russia even the first child was born, born from IVF using a frozen egg, but the technique was officially approved for clinical use only in 2012 year. Since then, the freezing of oocytes and their subsequent storage in a cryobank is a great way to postpone motherhood until better times, as the pop diva Alla Pugacheva did.
Cryopreservation means not just freezing, but maintaining all the functional abilities of the germ cell at low temperatures. The ovum, as it were, “slumbers” in anticipation of its time. The freezing procedure is a clear and standardized mechanism of action; the procedure is carried out only by high-class specialists using special equipment.
In Russia, it is still possible to preserve eggs for many years only in large reproductive centers. For comparison, in Israel, almost any clinic has such opportunities. But in our country, cryopreservation is only gaining momentum, and therefore it is not worth demanding everything right away.
Who May Need Cryopreservation?
The answer to this question is quite simple - any woman who plans to become a mother, but is not sure if she will be able to afford it in the near future. The only contraindication for cryopreservation is the woman's age.
If she is already 41 years old, doctors may refuse to carry out the procedure. After 35 years, oocytes rapidly age and lose quality.
No doctor can guarantee that a healthy child can be born from the egg of a mature woman. Although with age, everything is individual. For example, the aforementioned Alla Pugacheva applied for egg freezing services at 52 years old, and became the mother of twins who were conceived from frozen oocytes and carried by a surrogate mother at 64 years old.
Therefore, for women who are primarily interested in dealing with issues of education and professional career, for women who cannot meet the man of their dreams, but do not lose hope for a fateful meeting, cryopreservation will come in handy.
Eggs are also frozen for medical reasons, for example, in case of cancer in a woman before chemotherapy, before a course of radiation therapy, until the oocytes have undergone a destructive effect. The procedure is strongly advised for young women who are to have their ovaries removed, because after such an operation there will be no other eggs.
With the development of IVF, doctors have learned to obtain several eggs by stimulating the ovaries, and since there is no need to use all of them at once, the rest of the oocytes are frozen and stored in case IVF is unsuccessful and it will be necessary to repeat it, or for long-term storage in case the woman will want a second child in a few years and will need to do IVF again.
Cryopreservation of germ cells is highly recommended for women whose work is associated with harmful industrial influences, with radiation, with chemicals, as well as for the fair sex, whose work is associated with direct risks to life (military personnel in hot spots, special services employees, rescue women working in zone of disasters and catastrophes).
How does freezing take place?
Initially, doctors and scientists tried to freeze eggs slowly, lowering the temperature gradually. In this case, most of the eggs died, since the intracellular fluid turned into ice crystals and ruptured the oocyte shell. There was practically no suitable biomaterial left for subsequent fertilization. The method of slow and natural freezing was recognized as ineffective and is now practically abandoned.
Today, the eggs obtained by the puncture method are frozen by two main methods, it is they that allow keeping the largest number of oocytes in a normal state:
Slow exchange freezing. With it, the egg cell is first very slowly released from the intracellular fluid, then the space inside the oocyte is occupied by a special solution that does not crystallize when frozen.
- Vitrification. This is a very rapid cryofreezing method in which the egg is cooled to extremely low temperatures in seconds. In this case, the liquid inside the cell does not crystallize, but immediately passes into a glassy state.
The first method does not guarantee the absence of crystals, even if the entire procedure was carried out correctly. The percentage of living eggs with it is about 40-45%. During vitrification, eggs that are intact and capable of being fertilized after thawing are preserved more - up to 98%.
Freezing is carried out with liquid nitrogen at a temperature of minus 196 degrees Celsius or nitrogen vapor at a temperature of minus 180 degrees Celsius.
In order to get more eggs, the woman may be prescribed hormonal medications beforehand. They stimulate the maturation of not one, but several follicles. On the day of ovulation, which the doctor monitors by ultrasound, a woman under local or general anesthesia through the vagina will undergo a puncture of the ovaries and take ready and mature eggs, which will be immediately sent for sorting.
Specialists will assess the state of the oocytes, “discard” unsuitable ones and leave only ideal oocytes in the nutrient solution. They will be placed in special biocontainers in the form of tubes and frozen in one of the chosen ways. It should be understood that eggs found unsuitable are not used either for IVF or for freezing., since such oocytes increase the likelihood of conceiving a child with malformations and gross pathologies. They are simply disposed of.
It should also be understood that no method guarantees future pregnancy. Thawed oocytes can only be used for IVF or ICSI procedures.
Effects
Many women worry if the quality of the eggs will suffer after they are thawed. Experts are inclined to believe that no significant changes occur in the oocyte during the stay in suspended animation. Reproductologists note that embryos obtained from thawed female germ cells are usually more viable and strong. But this information has not yet been confirmed by either statistics or scientific facts. Therefore, it is quite reasonably questioned.
One thing is clear: if cryopreservation took place with at least the slightest violation of the requirements, there is no way to guarantee the safety of cell functions, as well as to predict the likelihood of their successful subsequent fertilization.
Violation of storage technology, temperature conditions (and oocytes are stored strictly at minus 196 degrees below 0), as well as errors of the medical staff during thawing can lead to the death of the entire volume of oocytes.
Frozen eggs do not affect the success of IVF, and failures in protocols should not be attributed to this factor. Success depends on the state of the endometrium, the woman's age, hormonal levels, the quality of her partner's sperm and the resulting set of genes.
How long can cells be stored?
Whichever method of freezing you choose, it will not affect the shelf life in any way. So far, medicine has insufficient data to determine the "critical" time limit, after which it would be impossible to keep cells in a stable state. Usually the material is stored for about 5 years, there have been cases of storage for 10 years. Terms beyond this are not mentioned in the medical literature, at least in official and verified sources.
How many treatments may be required?
Doctors tend to believe that for a successful IVF in the future, a woman would benefit from a cryo-storage of 15-20 eggs. It is clear that it is impossible to obtain such a number of oocytes in one period of ovarian stimulation. Therefore, some women have to go through the procedure of collecting and freezing her germ cells 3-4 times.
Some are limited to one procedure, in their cryobank there are about 5 eggs. This reserve, of course, may not be enough in the future, although sometimes the very first thawed egg is “successful” and “happy”.
Cons of techniques
The disadvantages of any of the freezing methods are that no one will give a 100% guarantee of the safety of eggs, just as there is no guarantee of a successful outcome of a subsequent pregnancy. In addition, the hormonal "shock" to which the woman's body is exposed in the process of stimulating the maturation of follicles, causes significant harm to the body. Depletion of the ovaries, hyperstimulation syndrome, as well as a violation of their functions are possible.
If suddenly a woman's plans change and she wants to conceive a baby naturally, it is not at all a fact that the state of her ovaries will allow her.
Another danger of the so-called "delayed motherhood" lies in the illusion of infinite time that a woman may have. It will seem to her that the most important thing - motherhood - is still ahead, she will have time for everything. And when the need arises, it may turn out that the age is not the same, and the state of health has changed. It is not worth relying too much on the oocytes stored in the cryobank.
All this, against the background of the rather high cost of the procedure, scares off many women. But the very prospect of postponed motherhood at the same time seduces no less of the fair sex.
The cost
In different regions of Russia, prices for cryopreservation of eggs may differ. The service is provided only by medical institutions that have the appropriate license from the country's Ministry of Health.
Much depends on the chosen method. Slow replacement freezing on average in Russia will cost 14-16 thousand rubles per procedure, and storage of material in a cryobank will cost about 1,500 rubles per month. Vetrification is somewhat more expensive - from 23 thousand rubles per procedure.
Some clinics offer comprehensive programs that include examination, preparation, ovarian stimulation, oocyte collection and freezing with a certain agreed storage period. Such programs cost about 75-90 thousand rubles.
Only women who do IVF under compulsory medical insurance can count on free freezing under a medical insurance policy from 2018... In this case, oocyte freezing is included in the list of services. In all other cases, a woman will have to provide for her "deferred motherhood" at her own expense.
For information on what methods of freezing eggs exist and how the process takes place, see the next video.
