Dr Robert Najdecki, the scientific director at Assisting Nature centre in Thessaloniki paid us a visit in order to speak about implantation problems. As some of you may already know, despite all the advances in reproductive medicine and all the progress made in the past few decades, the process of embryo implantation still remains the least understood part of pregnancy.
While the method by which embryos implant themselves within the uterus is understood on a basic level, the exact specifics are yet to be properly mapped out by fertility specialists. In order to help us understand how implantation actually works, Dr Najdecki chose to share a couple of patient stories with all of us. Before that, however, we need to understand what implantation failure actually is.
The term “implantation failure” is used to describe patients who have never shown increased hCG levels, as well as those in whom ultrasound evidence of a gestational sac was not found. It can apply to both patients undergoing assisted reproduction treatments as well as those who are trying to conceive naturally. There’s also the big bogeyman – repeated implantation failure. This term is used to describe patients in whom embryos don’t implant despite repeated attempts using assisted reproductive technology.
There are many factors which influence the implantation process. The environment inside the uterine cavity is a major one – from the thickness of the endometrial lining to its bacterial flora, the uterus must be ready to accept the embryo. Implantation relies on the successful cross-talk between the embryo and the uterus, with facilitation by many different factors, such as growth factors, cytokines, cell adhesion molecules, and transcription factors.
Large congenital abnormalities within the uterus – polyps, fibroids, and others – are well known to have a negative effect on embryo implantation. Smaller anatomical variations, however, are less understood and the degree to which they influence reproductive function isn’t fully known; however, they should not be underestimated.
Changes in endometrial receptivity may also contribute to repeated implantation failure. One of these changes may be the shift in optimal implantation timing. The Endometrial Receptivity Array test, also known as ERA, is used to determine how the optimal implantation window changes, based on 238 genetic markers.
The embryos themselves are an important piece of the puzzle. Their quality and health have a major impact on their odds; basically, the healthier they are, the better. Aneuploid embryos – those displaying chromosomal anomalies – aren’t well known for their implantation success. Even if they do, they carry additional risks to themselves and the mother which makes them a non-option.
Fortunately, PGT-A testing (previously known as PGS) allows embryologists to only choose those embryos which are genetically healthy, or euploid. In fact, modern embryology allows a staggering level of insight into embryo health, which has led to increased success rates.
Natural Killer cells derive their name from their ability to destroy leukemic cell lines. Many studies reveal that patients suffering from recurrent implantation failure have elevated levels of NK cells in both the uterus and the peripheral blood. These, as well as other autoimmune bodies are involved in biochemical pregnancy loss. Additionally, hereditary thrombophilias may be involved in unexplained pregnancy loss. Immunosuppressants and antithrombotic agents are used to manage these issues.
While other factors also have an impact on implantation, the embryo quality, uterine health, and autoimmune issues influence the process the most.
Now, lets discuss patient stories. The first case Dr Najdecki brought up concerned a 36 year old woman, recently married. She managed to conceive naturally twice; both of those pregnancies, however, ended with a miscarriage. She decided to try IVF. Two blastocyst stage embryos were transferred, however the patient did not end up pregnant. So, Dr Najdecki had a puzzle on his hands.
The first order of business was testing – a hysterosalpingography and uterine ultrasound revealed nothing out of the ordinary. Clearly, deeper investigation was required. It was a hysteroscopy that revealed the true reason for implantation failure – a partially septate uterus. It’s one of the more common deformations of the uterus, occurring during fetal development – before birth. Some women can go their entire lives without knowing they’re affected, and that’s what happened to our patient.
Septate uteruses are called that because of a membrane of skin – the deformity – divides the uterus in half. This membrane is called the septum. Treatment, fortunately, is very simple – a minimally invasive surgery to cut away the membrane. This is what our patient went through; a hysteroscopic septum excision. Additionally, Dr Najdecki recommended endometrial scratching; essentially, creating a small, controlled wound in the endometrial lining. This causes the uterus to grow its lining even thicker to compensate, which in turn leads to a higher chance of a successful implantation.
Following all of that, the patient and her medical staff decided on performing another embryo transfer during the next cycle. Two blastocyst embryos were transferred, and, wouldn’t you know it – a successful pregnancy occurred. Our story ends with the birth of two healthy children.
The second patient was a healthy 45 year old woman with a very low ovarian reserve – her AMH measured less than 0,1ng/ml. Before seeking Dr Najdecki’s help, she underwent an embryo transfer at another facility with a negative result. Once she was under Assisting Nature’s help, it was decided to place her in an exclusive egg donation program with additional PGT.
Her husband’s sperm was severely oligoasthenozoospermic – which basically means his semen had very low motility and sperm count. Twelve total eggs were used, eleven were successfully fertilised. Only six embryos managed to reach the blastocyst stage. PGT diagnostics revealed that out of those six, only two embryos were genetically healthy.
Eggs are tricky – not all of them are made the same. Some oocytes are of higher quality than others; in turn, that means not all eggs become embryos. This depends on the donor’s age and health, the stimulation protocol used and other factors.
The term blastulation rate is used by embryology laboratories to express the percentage of oocytes that reach the blastocyst stage. Assisting Nature boasts a blastulation rate of over 50%, which means for every six oocytes they fertilise, at least three will reach the blastocyst stage.
Sperm, however, is not the same; over the years, the average sperm morphology in the male population has been on the decline. Environmental, lifestyle and health factors are to blame. Emotional stress, smoking, excessive alcohol consumption, exposure to environmental toxins – these factors and more cause sperm quality to drop dramatically.
Obviously, sperm quality affects embryo quality. Low-quality sperm often results in aneuploid embryos being generated. As we already mentioned, embryos with chromosomal abnormalities are less likely to implant. By simply choosing euploid embryos, the pregnancy rate per embryo transfer rises to a level above 60%.
Out of the two euploid blastocysts that were generated, one was transferred with a positive result – the patient was pregnant and gave birth to a healthy baby boy. The second embryo was frozen for further use.
Sometimes, however, just choosing the right embryo is not enough. Patient number three was a 43 year old woman with a regular cycle undergoing an egg donation programme at Assisting Nature. One transfer of two euploid blastocysts failed to take hold.
Further investigation was required. A diagnostic hysterescopy was performed, although it didn’t reveal any anatomic abnormalities. An endometrial scratch was performed and a second transfer attempt was scheduled.
The combination of choosing an euploid blastocyst and increasing endometrial receptivity through an endometrial scratch – 10 days after a double blastocyst transfer, the patient had a positive blood pregnancy test. She eventually gave birth to a healthy baby.
Dr Najdecki sums up his presentation by concluding that recurrent implantation failure is a complex problem with a wide variety of causes and mechanisms. Fortunately, the variety of available treatment options is just as wide. As each patient’s needs and medical situation is different, personalised medicine is the best approach to dealing with their implantation issues. In general, however, adding PGT and endometrial scratching to the egg donation cycle, along with post-implantation treatment using immunosuppressants and antithrombotic agents as needed does a lot of work toward increasing the chances of a successful implantation.
This is a very old, but very serious issue, and opinions vary. Active hydrosalpinx with elevated white blood cells and other blood results is a problem for implantation due to the inflammatory reaction in the whole region, both the uterus and the salpinx. We are able to proceed with the in vitro cycles and collect the eggs, but we must absolutely treat the hydrosalpinx before embryo transfer.
Generally, there are many options and a lot of discussion about what the real influence of NK cells is – as I explained, they play an important role, but we are still far from understanding all these issues. In some cases, with recurrent implantation failure, the NK cell levels are elevated, but treatment using intralipid infusions is not always the solution. I know cases where trying to make something better, we elevated the levels of NK cells without any results and without any benefits for the patient. We try to measure NK cells, but we don’t really know what to do with elevated levels, and then we advise our patients to try some therapies or to wait and see what will happen. This is under investigation now, and we have many opinions – some researchers say that it’s not very important, while others disagree – generally the immunological contribution to implantation failure is probably very small – it’s better to concentrate on some issues that are well known, for example to ensure the embryos are euploid, as it’s important to know that you are using normal embryos. We have to make sure that the uterus and it’s anatomy is perfect by doing a hysteroscopy, as some very small anomalies can play a big role in implantation failure, and these anomalies are very difficult to diagnose with 3D or 4D ultrasound or a hysterosalpingography. If we are talking about 80-90% of the reasons for implantation failure, we still have about 5-10% which are immunological/other and are still under investigation.
Generally, we do either double or single embryo transfers. The single embryo transfer is absolutely correct in cases where we have done PGT and we know that we are using euploid embryos. In a case where we use unknown embryos, only blastocysts, and we don’t know of any previous history of implantation failure in the past, I’d advise you to start with a double blastocyst transfer. There is no difference between day 5 or day 6 – it’s a matter of the gynaecologist monitoring the endometrial stimulation and together with the lab, they will decide the day. In this case, we measured 5 days and in day 6, measuring from point 0, we perform the embryo transfer. If the result will be negative, then you have another two embryos to think about the possibility of doing a single or double embryo transfer. In the case of blastocysts, there are some morphological criteria they must fulfil before we vitrify them – if the blastocysts are vitrified, they are in good condition, and a check will be done after thawing them in the morning in the lab. In our lab, we are follow certain rules and we leave the embryos for a few hours (until afternoon) while monitoring their development, and if the blastocysts start to do automatic hatching or hatching is done, then this is a very good sign that these blastocysts are very active and alive. We have noticed that leaving the blastocysts until the afternoon allows us to collect more information about them. I think that every blastocyst that is alive and well after thawing has the possibility to be implanted in the uterus, but we of course choose these blastocysts in cooperation with the lab and the embryologists.
There are many differences – actually, the endometrial scratch is used in some methods starting with some plastic pipettes, which are very easy to perform and performed in the luteal or follicular phase of the cycle, and this is around 70% of all scratches. However, hysteroscopic scratching is a completely different and more direct method – when the operator, using the hysteroscope and the optic control, is able to see the anatomical situation inside the uterus, they are able to perform deeper scratching using scissors. The scissors are around 2-3mm, and we perform one line of scratching from one tube opening to the other tube opening. Sometimes when the uterus is bigger or a uterine septum is present, we perform two lines of scratching – then it’s so impressive to see how the uterine cavity opens after this scratching. So, there’s a very big difference, and I’d like to say that we are not able to compare these methods – we have used only hysteroscopic scratching for the last 2-3 years, and we are thinking of changing the name from ‘scratching’ to ‘excision’ – we open the fundus of the uterus, it’s only a few millimetres, but it’s very important for implantation.
When we are talking about our own eggs and our own blastocysts, there are many issues, and the most important issue is the quality of the blastocysts and their euploidy. If we know that the blastocyst is euploid, then there is no difference between the age of 30, 35 or 39 if the endometrium is growing properly, all the hormones are measured and the preparation of the endometrium is done correctly. Regarding egg donation cycles, we discuss this issue in one of our other podcasts – there are no differences in the implantation possibility based on the patient’s age, because the blastocysts are from young donors, and knowing their karyotype gives us the answers – in this case, it is the patient’s decision if she would like to have one or two blastocysts transferred. The difference in implantation potential is very small, so then, every decision is correct. If the patient is ready for twins, then we are able to do the double embryo transfer.
PGT (prenatal genetic testing) is the new name for PGS and is divided into some other categories by the ESHRE (European Society of Human Reproduction and Embryology). Talking about PGT, we are talking about former Prenatal Genetic Screening.
After one or two failed embryo transfers, but with good, euploid embryos, we are thinking about the implantation window. The ERA test is very useful, but it is performed at least one month before by sampling the endometrium, after which we will have the results. If we, as doctors, analyse the failed embryo transfer, then we can easily come to the conclusion that in the second or third embryo transfer cycle, we must change the day of the embryo transfer to either one day before or one day after. This is the first step. The ERA test does the same; after some measurements and analysis, the ERA test tells you to do the transfer either one day before or after. An experienced reproductive specialist and experienced lab can solve this problem in the second or the third embryo transfer. However, we do of course have the option of doing the ERA test, and there are many papers and research about the influence of ERA for better pregnancy percentage, but of course it is possible for patients to do it while being monitored by doctors.
Every cycle is different, and the measurement of the time of the implantation window is valid for a few months. After a few months, the cycles and the hormone profiles change, so the implantation window is not the same. Using some medicines like estrogens or progesterone can also influence the window. The truth is, that at any time, this window is very personal and after 6 months, you must think about repeating these measurements and the simulation of how the cycle works again.
I have seen many hysteroscopies and many blastocyst transfers, but the point is the absolute synchronisation in the cycle. The first step is to achieve a euploid blastocyst, and for this, PGT is absolutely necessary to have the information about the karyotype and the blastocyst. Then, working with the endometrium and the uterus and performing a more aggressive hysteroscopic scratching, I believe, will be the solution. I have seen many hysteroscopies and have performed many hysteroscopies after previous hysteroscopies, and the results are very different. I mean that the frozen embryo transfer is absolutely the same as fresh transfer – we are supporting the freezing strategy, and the results are even better than in fresh cycles, because we are able to work with the endometrium independently, without time pressure – in the next cycle we are focused only on the endometrium and monitoring its correct growth. In my opinion, the most important is a euploid blastocyst, second is good preparation with hysteroscopy, and third is a properly prepared endometrium for the transfer.
There are differing opinions about EmbryoGlue having a positive influence as well as opinions about its negative influence. In our lab, we don’t use EmbryoGlue very often, because in our opinion, it’s not something valuable for the future development and for the implantation process.
There are many different opinions about what the level of progesterone should be in the luteal phase, and how to support it. Actually, if we believe in medicine and research, we must consider that the normal luteal phase support is enough for proper implantation. We must try another form of progesterone – we are now using subcutaneous injections of progesterone, waiting for stable levels of progesterone. But, in many cases, we cross the progesterone injections with vaginal gel and with oral drugs, to be sure that the level of progesterone is correct, and it’s easier to have stable levels. This is under investigation, but it is difficult to say that this is definitely the reason for failure. First if all, we don’t know the patient’s proper progesterone level – we haven’t got any previous research about it and it’s not possible to do it. We use some protocols for this, and a lot of them are very successful. I think that in the case of failure, the question is if the blastocyst was euploid, and if the karyotype of the blastocyst was correct. If we have recurring implantation failure after embyro transfer with euploid embryos, there is a clear answer: we must look into the uterus and into immunological mechanism, because the blastocyst is perfect. If we don’t know about the karyotype of the embryo, then there can be many reasons for the failure – first of all we must ensure the embryo is euploid, and then have really good, normal support with progesterone with the next cycle, and I’d like to advise you to use two or three different types of progesterone – endovaginally, orally or injected.
These are two absolutely different techniques. During the laparoscopy we see the uterus, tubes and ovaries from the outside – it’s a very important method for diagnosis of, for example, endometriosis, which affects the structures outside of the uterus. A hysteroscopy, however, concentrates only on the uterine cavity. Therefore, there is no connection between these two examinations.
My first question is about the karyotype of the embyros – if the blastocysts are euploid or not. My advice would be to proceed with PGT and start again with planning a treatment plan and in this way, be sure that we are transferring normal and proper embryos. In around 60% of cases of unknown infertility, we are talking about embryo failure, so improper karyotype. If the embryos are checked and found to be proper, and after one or two transfers there is still no pregnancy, then we must look for some anomalies in the uterus or some asynchronisation of the endometrial maturation. 13/14mm is a very good lining thickness, but even 7mm lining thickness is enough to perform an embryo transfer. In this case, once we have information about the embryos, then maybe the next step would be to perform an ERA test, to find the exact implantation window.
Without information on the karyotype of the blastocysts, we are able to make the same mistake again and again – we know of cases where 6,7,8 blastocysts are abnormal and this would explain the implantation failures. If we have the embryos frozen, the issue is more complicated because there is an option for a very quick PGT but it will be a 7 day embryo transfer – it is possible but it is under investigation to see if the results are the same as with a day 6 transfer. One solution is to agree with the statistics and to do this embryo transfer, and wait for good fate and to get pregnant, and if not, then to proceed with the PGT in all the blastocysts. This will give us the answers if there is any sense in continuing with the rest of the blastocysts, and without this information it is very difficult to decide what to do.
The bigger polyps and the bigger abnormalities are very well known – but the smaller ones also may have an influence and cause negative results. A 2mm polyp is probably found by ultrasound, and because of this method, we cannot be sure that this is actually a polyp. One way to be absolutely sure is to perform a hysteroscopy. A hysteroscopy with polyp removal and scissor scratching may be the solution for you in this case.
Actually, we perform hysteroscopic scratching in the cycle before the ET, but if we notice in the next cycle after the scratching that something has gone wrong and we see a liquid in the uterine cavity, then we would stop the monitoring of this cycle and we would focus on the following one. The second cycle after the hysteroscopy or the third – this is what we have found in our experience. We never perform an embryo transfer in the same cycle as the hysteroscopy – this is absolutely impossible. We perform the scratching in the follicular phase, 2-3 days after menstruation stops, and in every case, we use contraceptive pills to be sure of the level and the growing of the endometrium, and the next cycle or the cycle after will be the best for the implantation window.
If you decide to proceed with an egg donation programme, it’s probably a very good decision – first of all, because we will use a young donor’s eggs, but also in your case, I’d advise you to proceed with PGT so you have an absolutely clear view on the embryos before you transfer. It’s a matter of price, but I think that it’s absolutely worth it for you to not pay for multiple embryo transfers but to pay once for PGT and only transfer the euploid embryos. Once you have euploid embryos, you can prepare your endometrium by a hysteroscopic scratching or proceed with the first transfer without the scratching, and in the case of failure, then do scratching and transfer the euploid embryo. I think in a few years, it will be in the guidelines to only transfer euploid embyros and to prepare the uterus with a hysteroscopic scratching.
In your case, we must support your cycle with medicines, in order to have a normal cycle with bleeding and menstruation. This is very important to support your future embryo transfer. In my opinion, if we have this abnormality, and for example you menstruate every two or three months, then it’s better to use some substitution medicines or very light contraception to keep your cycle normal and to have the option to proceed with an embryo transfer every month.
If you have AMH 16, there is a possibility for you to use your own eggs, but only with the PGT procedure. It is well known that every woman who is around 40 years old, statistically, produces around 10 eggs per year. I say 10 eggs because you will have 1-2 menstrual abnormalities without egg production, so if we are talking about 10 eggs per year, then it is possible for 7-8 of those to be abnormal. Looking for those 1-2 normal eggs is difficult, and then we must realise that every year after 30 it’s getting more and more difficult. Without PGT procedures, we have no idea what we are transferring- I advise you to try with your eggs, but only with PGT. If good, euploid blastocysts are found, then it is possible to win this war. If there are no euploid blastocysts, then egg donation would be an option for you, instead of waiting and losing time doing other procedures. PGT with your own eggs, and then if not, then an egg donation programme.
This is a very simple issue and it’s easy to investigate this – these are signs of inflammatory disease. It may be connected with our procedures or not. Sometimes, it could be tooth inflammation, or something completely unrelated, so it’s something for an internal medicine doctor to investigate, and to be sure that in the next attempt, the white blood cell count should be under 9000. There are also other inflammatory index measurements which you can monitor with your doctor to solve this issue.
Before the hysteroscopy, we measure all the blood factors and then there are ways to do it, for example to change this medicine for Heparin for around the time of the hysteroscopy. There are no elevated risks for performing a hysteroscopy on a patient with Heparin support, and we have done it many times without any problems. If the operator is experienced and the hysteroscopy is short, then there shouldn’t be any issues with bleeding or anything else. However, we must discuss this with the anaesthesiologist and other specialists to solve this issue, and always in cooperation with your gynaecologist, however this procedure is very possible. This procedure is more diagnostic than therapeutic, and the incisions in the fundus of the uterus are very small, 2-3mm incisions where we go through the tissue until we see the blood vessels – the point isn’t to damage the blood vessels but to stop in the layer above the vessels. The risks are very small and the experience of the operator is very important in this case.