Does embryo monitoring boost IVF success? What is it and how it works?
What is embryo monitoring and what role does it play during IVF treatment? What are advantages of using real-time monitoring? Does it affect embryo quality or their selection?
All you have to know is presented by experts in 3on1 #IVFANSWERS:
- Małgorzata Wójt – Embryologist at Salve Medica
- Dr Andrii Sozonyk – Head Doctor, obstetrician-gynaecologist Parens IVF Center
- Dr Ruth Sánchez – Gynecologist at PreGen, The Reproduction Unit at Clinica Vistahermosa
Answer from embryologist Wójt
It’s a very difficult question. We have different types of time-lapse system: EmbryoScope, Esco system, Primo Vision and few others. They are all based on the method of pictures that are taken every few minutes without disturbing the conditions in which embryos are kept. Time-lapse is a very helpful tool in the hands of embryologists. Before the era of time-lapse system, we had only the possibility of morphological assessment. For example, the assessment of cleavage stage is based on two main criteria: the number of cells and their morphology. The blastocyst scoring is also based on two different criteria: the expansion state of blastocyst and the consistency of the inner cell mass and trophectoderm cells. Time-lapse gives us more information. Morphokinetics, as seen with time-lapse, can enhance the power of embryo selection because it allows for morphology to be assessed more accurately.
Time-lapse embryo monitoring allows continuous and – what’s very important – non-invasive embryo observation, without the need to remove the embryo from the incubator and the optimal culture conditions. The extra information about the cleavage pattern, morphological changes and embryo development dynamics could help us to identify the embryo with the higher potential. This assessment is very closely related to the optimal time of the individual embryonic division.
In my opinion, time-lapse is particularly important in two situations. Firstly, it’s when we perform the transfer on the second or the third day. At this stage of the embryo development, morphokinetics is very important. Embryos that are observed up to the blastocyst stage, undergo a kind of natural selection. Some of them, especially the ones with big defects, stop developing. Secondly, it’s the situation when we have more embryos than we can transfer. Two blastocysts, looking the same, do not always have the same potential. When we compare two equally looking blastocysts, we can sometimes see small and sometimes large gaps in the embryo development.
Unfortunately, sometimes things that seem obvious and beneficial to us, have no confirmation in clinical trials. Basing on the Cochrane Library, there are several clinical trials that say there is no clear evidence that time-lapse system increases pregnancy or live-birth rates. This means that, although time-lapse system is a very helpful device, it will not replace a good embryologist.
Answer from Dr Sozonyk
The morphological method is the main indicator of how we evaluate embryo quality. Embryos are evaluated according to the following criteria: the number of blastomers, the quality of blastomers and the presence of fragmentation. However, this is old method of assessing the quality of embryos is not without drawbacks and it is subjective. The embryo is extremely variable in its development. Ugly duckling embryo quality on the second day can develop into a completely healthy and very pretty baby.
Currently, a new game changer – the EmbryoScope method – turned up for assessing the quality of embryos. Its principle is the following: every 10-20 minutes a snapshot of the embryo is made in 7 layers using a computer program. The pictures are superimposed one on top of other and a short video summary of each embryo is obtained. EmbryoScope is the household name of the device of the new generation. At its core, it’s an incubator that supports the conditions for the growth and development of cultured embryos. But there is a difference which makes the breakthrough in the reproductive biology. Using the lenses and the camera built into EmbryoScope, we can observe what change occurred in vitro with embryos from the moment of fertilisation and up to 5-6 days of the development. The camera takes pictures every few minutes. The images subsequently form a video in which we see how the embryo was at what time, in what sequence it grows and the fragmentation of the cells of the embryo progress.
Recently a large study was conducted and the result showed the analysis of those embryos that gave pregnancy and subsequent births. It turned out that all those embryos had similar crushing time intervals and other time-related morphological criteria. The so-called time lapse system showed that a new direction of morphology was born: morphokinetics. Using retrospective analysis, morphokinetics gives us answers to many questions that were previously a mystery.
This new technology can significantly increase the chances of pregnancy. On one hand, it is no longer necessary to get the embryo out of the incubator every day to study it under a microscope.
Now the embryo is not affected by physical factors, which it is most sensitive to at this stage of its development: temperature changes, light, vibrations or sound. On the other hand, we can select the best embryos with the highest potential of implantation and pregnancy. EmbryoScope allows us to see in real time what we previously could only guess about. Now we can replace assumptions, such as what really happened to the embryo from the moment we saw it for the last time, with full science confidence. It is also important that future parents can subsequently see how the life of their unborn child progressed from minute to minute.
The use of EmbryScope will allow even wider access to the selective transfer of one embryo. A selective transfer of one embryo allows us to reduce the number of multiple pregnancies without reducing the overall pregnancy rate. It significantly minimises the risk of complications for both the mother and her unborn child. Preimplantation genetic screening (PGS) makes it possible to select euploid embryos with a high probability of implantation. It allows to increase the effectiveness of IVF programs, reduce the frequency of early reproductive loses and increase the frequency of gestation.
Answer from Dr Sánchez
EmbryoGlue is very new in IVF. At the moment, a lot of laboratories are looking into it. It is actually a medium that we use when we transfer the embryos. They stay there for some time. This medium usually contains high concentration of proteins. It is a protein called albumin. It has been shown in some studies that if an embryo develops in this fluid culture, it creates a very thick sticky matrix that can help it attach better to the lining of the womb. So actually it was a very clever idea.
Initially, we were very skeptical about how safe it could be for an embryo to stay in this medium before we transfer it into the uterus. The initial studies have shown that it is completely safe for the embryo, it doesn’t have any adverse effects on it. Now there is a lot of study going on whether it has some benefit or not.
Recently there was a study which, in medical terms, we call a Cochrane study. These are doctors who are gathering all the data from smaller studies related to this topic and trying to see whether this helps or not. In general, it has been shown that it has no benefit in the success rates.
But there is a very small group of patients that it actually has shown some benefit in. These patients are usually 42 years old and they had 2 IVF attempts with the implantation failure. They created good quality blastocysts that were not able to implant. In this patients, EmbryoGlue could have some benefit. For this reason, in our lab we are considering to start using this technology. Our lab director is trying to find appropriate funds so we can get this medium and start using it in a very well selected population of patients.
Unfortunately, this medium is a little bit expensive. It costs about 600 euros. You have to be very sure where to put it and whether you have a clear indication to put it. So we are looking into it. There could be a potential benefit for some people to use it. So the answer is: yes, we consider using it. However, only in a very well selected population group – not in all cases, as it hasn’t shown any clear benefit for all patients doing IVF.