How is Embryo Freezing Done?
The first frozen embryo baby was born in 1984. Thanks to the eggs collected from the mother-to-be with the embryo freezing method, there is a chance to apply for IVF treatment again. If the embryos are of good quality and are taken when the mother’s age is appropriate, the chance of giving birth to healthy babies increases in later ages. For this reason, one of the most curious issues of couples is the question “How is the embryo freezing process done?”.
What are the advantages of embryo freezing?
Since the number of embryos transferred in IVF treatment is limited, the remaining quality embryos are then evaluated. When the result is negative, there may be a chance of a new medication and a re-embryo transfer without egg collection. In this way, the mother-to-be is less tired, the pressure on the couple in the financial sense is reduced and the chance of pregnancy increases. When the pregnancy results in a live birth, the frozen embryo can be used for the second child again in the following years without the need for medication.
Especially in the case of PCOS, Polycystic Ovary Syndrome, when the ovaries of the patients work too much and produce more eggs than necessary, the hormones increase and this increase can reduce the possibility of the embryo to attach to the mother’s womb. Or excessive egg production can continue, leading to OHSS status. In such cases, all embryos of our patients are frozen and the general condition of the patient is postponed until the embryo is ready for transfer.
In the IVF treatment process of the mother-to-be, endometrial thickness insufficiency may occur, endometrial polyp may be detected or fracture bleeding may occur. In such cases, too, the embryos are frozen and the transfer takes place later.
Embryo freezing in cancer treatment or before radiotherapy is important to protect the patient’s chance of becoming a mother after treatment.
How are embryos frozen?
Embryos can be frozen at any stage thanks to developing technological methods. Embryos are placed in special carrier apparatus after undergoing various processes in a protective solution. After this stage, it is frozen in liquid nitrogen at -196 degrees and safely stored in compartments specially allocated to each patient. Frozen embryo cells are removed from liquid nitrogen when they are to be thawed. These cells are then dissolved at appropriate temperatures and solutions. Then, the embryos taken to a special culture medium are put into special devices that mimic the mother’s womb called incubators. If the embryo is in good condition, it is transferred.
How long are embryos frozen?
This period is different for each country. The retention period of frozen embryos in Turkey is 5 years and those who want to extend the period must obtain permission from the necessary authorities.
What is the viability and pregnancy rate when frozen embryos are thawed?
In the case of thawing frozen embryos, the chances of preserving viability rates are quite high. The preservation rates of embryos are up to 95%. In other words, 9 out of every 10 embryos that are frozen have a chance of pregnancy. However, the reason for the low cold treatment thawing rates mentioned in different centers is; egg and sperm quality. In addition, insufficient laboratory conditions in the environment of embryo rearing also affect this failure. If the embryos continue to develop well when thawed, pregnancy rates may be the same as fresh embryo transfer, and in some cases even higher.
How are thawed embryos transferred?
In order to prepare the mother-to-be for embryo transfer to the uterus, it is necessary to first prepare the endometrium (uterine wall) and ensure that it reaches sufficient thickness. For this, it is preferred that it is prepared with a very mild treatment with natural cycles or medications containing estrogen hormone.
Are babies born with frozen embryos healthy?
Babies born from frozen and then thawed embryos did not have a risk ratio for any anomaly, mental retardation or other problem. For this reason, no more risk is expected than the anomaly risks that may occur in pregnancies that are eliminated through intercourse.