How important are laboratory conditions in the success of IVF treatment?
One of the most important factors in IVF treatment is laboratory conditions, and they play a very critical role in the success of treatment. Achieving maximum efficiency in the laboratory is only possible with a well-planned and organized laboratory, advanced technological equipment, experienced embryologists, meticulous work, and a serious quality control system. Since the factors determining success are always hidden in the details, the working environment and equipment must be checked regularly and frequently, and any problems must be resolved immediately.
How is the embryo transfer restriction applied in IVF?
In IVF treatment, the number of embryos to be transferred varies between 1 and 2. The woman’s age, the quality of the embryos, and previous IVF attempts are taken into consideration when determining the number of embryos. According to the regulations in Türkiye, in the first two IVF treatments for women under the age of 35, 1 embryo can be transferred, and in subsequent treatments, a maximum of 2 embryos can be transferred. For women aged 35 and older, regardless of previous IVF attempts, a maximum of 2 embryos can be transferred.
How is the day of embryo transfer decided?
Before deciding on the day of embryo transfer, the embryology team and physicians must evaluate the patient profile together.
The main factors taken into consideration are the reason why IVF treatment was chosen, the results of any previous attempts, the woman’s age, embryo development characteristics, whether PGT will be performed, the number of eggs retrieved and embryos developed, and the daily development of the embryos. Embryo transfer can be performed as early as day 2 and as late as day 6, meaning on days 2, 3, 4, 5, or 6.
What happens to embryos that are not transferred and not used?
Good-quality embryos remaining after transfer can be frozen and stored.
These embryos, which are not transferred but have a high chance of pregnancy and show good-quality development, can be frozen and stored for future use. Frozen embryos may be stored for up to five years with the written consent of the couple. In this way, the financial and medical burden of a new IVF treatment can be reduced through a simpler method.
What does blastocyst mean?
To identify the best embryo during embryo selection, embryos are followed in the laboratory until the fifth day. Embryos with higher pregnancy potential on day 5 are called blastocysts.
After fertilization, the zygote (fertilized egg) begins to divide and develop. This occurs in the same way in both natural pregnancies and IVF pregnancies. The fertilized egg becomes a group of 2, 4, and then 8 cells. On the second and third days, it is a solid cluster of 4–8 cells without a cavity. By the fifth day after fertilization, a cavity forms inside, surrounded by cells; this stage is called the blastocyst. In natural pregnancies, this is the stage the embryo reaches just before attaching to the uterine wall.
In which situations can embryo freezing be performed?
To effectively use embryo freezing and thawing treatments, the IVF center must provide a very good cryopreservation service. In addition to technological infrastructure, the experience of embryologists is very important.
The quality and selection of the embryos to be frozen are the first important steps. After that, the freezing method and the experience of the embryologists become important. Although many IVF centers offer embryo freezing and thawing services, there are serious differences in success rates.
In a high-quality IVF center, the number of patients offered embryo freezing is high. More importantly, the pregnancy rates achieved with frozen-thawed embryos are at least as high as, and sometimes higher than, those achieved with fresh embryos because the treatment is performed in a more natural uterine environment.
Who is embryo freezing recommended for?
With advances in technology, the patient profile for whom embryo freezing is recommended has also changed. In the past, it was recommended only for couples with a certain number and quality of embryos. Today, it may also be recommended for couples with only one good-quality embryo. The important factor is the developmental stage and quality of the embryo.
Embryo freezing is also an effective solution in cases where treatment must be stopped or postponed. For example, in women with Ovarian Hyperstimulation Syndrome, where the ovaries respond excessively to the medications used, all embryos can be frozen in their early stages. When the patient’s condition returns to normal, the embryos can be thawed and transferred, often resulting in high pregnancy rates.
Some clinics also use embryo freezing in cases where high doses of hormones may reduce the receptivity of the uterine lining or where conditions such as fibroids or polyps may prevent embryo implantation.
Another important use of embryo freezing is for couples planning genetic testing of embryos. Embryos can be accumulated through several treatment cycles and then tested together, reducing the cost of genetic testing.
When and for whom can oocyte (egg) freezing be performed?
As with embryos, eggs can also be frozen and stored successfully. Eggs collected at a younger age and frozen preserve their quality for future years.
In Türkiye, the Ministry of Health regulates the medical conditions under which women may freeze their eggs. Women who are unmarried but have reduced ovarian reserve, have not yet given birth, or have a family history of early menopause may freeze their eggs if this condition is documented by a medical board consisting of three specialists.
Egg freezing is also possible before treatments such as chemotherapy or radiotherapy, which may damage eggs, or before surgeries that may result in loss of fertility, such as removal of the ovaries. In our center, eggs are frozen using the vitrification method. Improvements in the solutions and protocols used have made it possible to achieve results similar to fresh treatments.
Frozen eggs may be stored for up to five years under current regulations, although this period may be extended with approval from the Ministry of Health.
What is Comparative Genomic Hybridization (CGH) – Comprehensive Chromosome Screening?
Until recently, only certain chromosomes could be examined. Today, however, all chromosomes can be analyzed in detail through comprehensive chromosome screening. This method allows all 24 chromosomes to be examined before embryo transfer, unlike older methods such as FISH, which only evaluate selected chromosomes.
Will an embryo found normal in all chromosomes always result in pregnancy?
Failure to achieve pregnancy or early pregnancy loss due to chromosomal abnormalities can occur at any age, but the risk is much higher in women over 35. Selecting genetically normal embryos through comprehensive chromosome screening significantly reduces this risk. However, obtaining a genetically normal embryo alone is not enough; a healthy uterus is also essential.
How does this method differ from the PGT method commonly used today?
Today, many clinics use PGT with a technique called FISH, which usually evaluates only selected chromosomes (5, 7, or 9). With PGT that screens 9 chromosomes, 60–80% of possible chromosomal abnormalities can be detected.
However, because the remaining 20–40% of chromosomal abnormalities cannot be detected, an embryo found “normal” after examination of only 9 chromosomes may still fail to result in pregnancy because of an undetected abnormality.
With comprehensive chromosome screening, all chromosome regions can be seen in detail, and transferring an embryo that is normal in all 24 chromosomes may increase pregnancy rates.
How is the embryo monitoring system used?
Our IVF laboratory follows all innovations in the field to provide services at world standards and continuously increase success rates. For this purpose, a Continuous Embryo Monitoring System has begun to be used in our IVF laboratory.
The embryo monitoring system allows your embryo to develop without excessive exposure to the external environment. By observing the embryo’s rate of division, it helps us identify the embryo with the highest implantation potential, thereby increasing pregnancy rates.
With current systems, embryos are removed from incubators at certain times for evaluation, exposing them to the outside environment. This exposure may reduce embryo quality and implantation potential. With the embryo monitoring system, this risk is eliminated because the embryo is monitored continuously inside the incubator.
Thanks to this system, you can follow the development of your embryos in real time and, if you wish, witness this remarkable journey yourself.