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Understand The Embryo Freezing Procedure

Embryo freezing is a medical technique in which embryos are frozen at a very low temperature of -196 degrees Celsius for a predetermined period. It is also known as embryo cryopreservation. The embryos stored are later used in the Frozen Embryo Transfer (FET) procedure in infertility treatments such as IVF.

In modern times, advanced medical procedures have taken a significant place in treating the medical conditions of patients irrespective of their healthcare issues. Infertility is one of the prime issues for couples who are unable to conceive naturally. Along with treatments created for curing infertility issues, various other medical procedures are introduced, which are combined with the chosen treatments to receive the desired results for the patients. In recent years, the demand for cryopreservation procedures has significantly increased due to the increased support of infertility experts along with government funding, which has motivated more individuals to go for the embryo freezing procedure. You will be surprised

to know that embryo freezing increases the chances of reproduction by 70% when compared to cases which go for natural conception or conventional IVF procedure. This proves to be useful for couples struggling hard to have babies. In countries like Europe, NHS supports couples’ In Vitro Fertilization (IVF) cycles to a great extent and helps them receive up to three cycles at affordable and reasonable costs. Europe and North America have recorded the highest growth in the use of IVF treatment, which has proved to be very significant for patients. The usage of eggs, sperm, and embryo freezing in infertility treatments has also reached the next level in these continents. In the countries of Asia Pacific, the implementation of infertility treatments has increased significantly because of fertility tourism and the rise in awareness related to the treatment. In this article, you will find information about different aspects of the embryo preservation procedure and its contribution to the success of the IVF procedure.

Embryo Freezing or Embryo Cryopreservation procedure:

Embryo freezing procedure is a medical technique in which an embryo formed in the IVF laboratory is stored at a specific temperature. The best temperature at which infertility experts recommend storage of embryos in this technique is around -196 degrees Celsius. This temperature is proven to be the most suitable one for preserving embryos in the medical laboratory in the embryo bank or fertility clinic. As per the National Embryo Donation Academy, around five lakhs of embryos were stored in embryo cryopreservation procedures in the United States alone. Also, the procedure of embryo cryopreservation is performed within one to six days of the formation of the quality embryo.

History of Embryo Freezing:

Embryo Freezing first came into notice when the first baby was born in the year 1984. The baby born with the assistance of a frozen embryo was named Zoe. The scientists of Monash University mentioned that the news of the baby’s birth was hidden for two weeks to provide the desired protection to the baby’s family. Professor John Leeton was a significant part of the procedure of In Vitro Fertilization, which helped in the birth of the baby. As per the reports of IVF doctors, it was found that the egg and sperm of the couple were fertilized in the medical laboratory. The embryo, which was thus formed, was preserved for two months before progressing with the transfer of the embryo into the uterus of the woman.

Fortunately, the embryo was implanted with success. The woman got pregnant, and the entire team leading the procedure was happy with the accomplishment.

When is the Embryo Freezing procedure recommended?

There are certain specific and crucial conditions in which procedures, such as embryo infertility experts, recommend the freezing technique. Embryo freezing procedure is advised to patients in the following cases:

Intentional delay of conception: In recent years, a number of individuals have headed towards a life where professional priorities are considered before building a family. Here, a couple or even a single individual choosing a donor egg or sperm has decided to start a family after a couple of years. In such cases, the embryo-freezing procedure is selected for

the couple. It helps them to store embryos or embryos in the right conditions. As per the recent research published in the news publications, it is found that Total Fertility Rate (TFR) is decreasing at a constant rate. This has occurred due to the rise in the scenario of delayed marriages and late planning of babies.

Primary health conditions: There are various health conditions that take a toll on the fertility levels of the body. This makes an individual or couple think about safeguarding their eggs, sperm, or embryos for future use to start a family without facing many obstacles in their path towards parenthood. If a couple plans to have a baby, then they can simply take the assistance of the embryos stored in the medical laboratory. Some such health conditions include cancer, which needs to be dealt with in a positive manner. Here, embryo cryopreservation will help individuals and couples have babies in the later years of their life as well.

Will to donate embryos: Most of the couples that go for the embryo freezing procedure are often left with quality embryos. These embryos can be utilized for In Vitro Fertilization treatment of couples who are unable to conceive due to poor quality of embryos formed with their respective sperms or eggs. If a couple has chosen an embryo cryopreservation procedure, then they can help other couples go for the embryo donation. Another couple can quickly pick up the embryo donation procedure, thus improving chances of success in the IVF procedure with a positive pregnancy.

How do you prepare for the Embryo Freezing/ Embryo Cryopreservation procedure?

Patients need to understand that the embryo-freezing procedure requires some specific preparation to ensure that the procedure ultimately leads to a successful pregnancy for the couple opting for it. Choosing the best and most proven tips will help couples prepare for the embryo-freezing procedure and receive the desired results.

Blood tests are important for screening purposes. This helps in finding out the actual health status of the patients. Ovarian reserve testing is performed to find out the quality and number of eggs. Follicle stimulating hormone (FSH) and estradiol are tested to find out egg quality and number in the concerned women.

Infectious disease screening is also performed to know whether the woman is affected with HIV, Hepatitis B, and C. This prevents the passage of these serious healthcare conditions into the baby, who will be born with the help of the IVF procedure along with frozen embryos.

These tests are common for sperm, eggs, and embryo freezing procedures as well. Before starting with the procedure, couples need to make sure that they go for all the recommended medical tests as suggested by the infertility experts. Time to time monitoring is done under the guidance of the infertility specialists to make sure that the embryo cryopreservation procedure takes place in the right manner.

Methods of Embryo Freezing procedure:

Embryo freezing procedure comprises of different methods, which are utilized as per the requirement of the infertility case of the patients. The most crucial and commonly used

embryo freezing procedure includes Slow Programmable Freezing (SPF) popularly known as Slow Freezing along with Vitrification procedure. Each of these methods has its own set of pros and cons which are considered while choosing for the concerned procedure.

Slow Programmable Freezing (SPF)

Slow Programmable Freezing (SPF) is one of the top methods, which assist in fertility preservation from several years now. This procedure was utilized for the first time in the year 1986. This procedure was the only reliable way to freeze eggs for nearly 2 decades until procedures like vitrification were introduced. Here, a cryoprotective agent is used to preserve the embryo for a considerable period of time, as recommended by the infertility expert himself. The targeted embryo is stored at a temperature of -196 degrees to prevent any kind of damage throughout the time period of embryo cryopreservation procedure. The natural biological processes are shut down naturally in this procedure. Proper care is taken with respect to the cells, as around 30% of the cells in the embryos

cannot successfully complete the insemination process, which can also tolerate the thawing procedure. The success rates of the slow freezing or slow programmable freezing (SPF) technique are a considerable one. The slow freezing procedure is possible only in the pronuclear stages. This stage of embryo development is popularly known

as PN stage. Therefore, if this procedure is used, then inseminated egg cells are taken for successful completion of the same. This is because the inseminated cells have a different level of sensitivity than the non-sensitive types of cells present in the embryo. The time period, which is involved in the slow programmable freezing procedure, is around

hours. This procedure is very less utilized these days. This is because of the increased time consumption.


The procedure of vitrification involves various steps where the specialist utilizes a very high freezing rate when considered on per minute basis. This helps in getting the embryos frozen at a very quick rate. One of the major differences of slow programmable freezing and vitrification is that the later procedure is a modern one and the success rates of vitrification are much higher than the slow freezing procedure. These days, infertility experts

highly favor the utilization of vitrification procedure with the help of which embryo freezing can occur quickly without mere wastage of time and energy.