Why do some embryos stop growing in the IVF lab ? Growth arrest of embryos !

Stages of human pre-implantation embryo development. Phase-contrast images of human embryo development from day (d) 0 to day 7. Following fertilization, embryos undergo a series of mitotic cell divisions. Arrowheads in d0 and d1 indicate pronuclei. On or around day 4, the embryo compacts, resulting in the formation of a morula that consists of cells (or blastomeres) in a compact cluster contained within the zona pellucida (the glycoprotein layer that surrounds the embryo). The blastocyst, which forms on day 5, is a fluid-filled structure composed of an inner cell mass (white arrowhead) and trophectoderm (gray arrowhead). On day 6, the blastocyst ‘hatches’ from the zona pellucida and it is ready to implant into the uterine wall on day 7.Courtesy : dev.biologists.org

If you have gone through IVF, you may have heard your IVF doctor or embryologist say - “Some of your embryos stopped developing (got arrested), and we had to discard them .” There are some unlucky women who end up with no embryos to transfer,  because all their embryos stopped developing at some time point during their preimplantation growth ! Why does this “developmental arrest “of embryos happen ? Are there any ways to prevent it ?

It is a well-known fact that 10-15% of IVF embryos permanently arrest during mitosis (during cell division) at the 2-4 cell cleavage stage. Some arrest immediately following fertilization and will not divide past the one-celled stage. Over half of all arrested human embryos display chromosomal abnormalities (genetic defect). Hence it is assumed that developmental arrest happens in order to prevent the growth of abnormal or poor quality embryos.

. An embryo might undergo developmental arrest because of :

1)      Sub-optimal culture conditions

2)      Chromosomal abnormalities

3)      Failure to activate its embryonic genome

4)      Mitochondrial defects

When embryos are exposed to sub-optimal culture conditions in the IVF lab ( for example, when the lab incubators malfunction; or if there is an infection in the culture medium) . they might stop dividing further. If you learn that the greater proportion of your embryos have stopped growing, please ask the embryologist about the possibility of lab error, and ask them to show you how embryos from other patients are faring under the same culture conditions. This will help you to understand whether lab conditions have played a role in the growth arrest of your embryos . Some labs maybe understandably reluctant to share this information with you, and this should serve as a red flag.

Oocytes from women of advanced maternal age have a higher chance of carrying genetic defects such as aneuploidy (wrong number of chromosomes). Such oocytes, when fertilized , can give rise to embryos; but depending on the chromosomal abnormality they are carrying, they stop growing at different time period. Some do not get past the single-celled stage (zygote stage); some stop developing before they are transferred to the uterus (in the IVF lab petri dish); some after being transferred to the uterus; and some even after implantation (remember that 60% of miscarriages happen because of a genetic abnormality in the embryo !). Genetic lesions in embryos are one of the commonest factors for developmental arrest, which is why embryos from older women are more prone to growth arrest when compared to embryos of younger women !

When the egg and the sperm fuse together , fertilization happens and an embryo is formed. The embryo thus formed carries the genetic material from both the mother and the father. On the first day of its formation , an embryo is just a single-celled entity. This single-celled embryo develops into a full-fledged baby provided it carries all the necessary genetic information .  The initial few cell divisions of a single celled embryo are carried out by the information provided by the oocyte (egg) and not by the sperm . The cytoplasm of the egg contains key information which will help the embryo to divide upto the 4-8 cell stage. It is only after the the 4-8 cell stage that the embryos’ own genome gets activated , and it produces the information necessary for further development. In some embryos this genomic activation fail to happen and they stop developing past the 4-8 cell stage, causing developmental arrest.

An embryo needs energy for its development.  The energy requirement of the dividing embryo is met by specialized organelles called mitochondria, which are also called as “cellular power plants”. They carry their own genetic material. They synthesize energy molecules called ATP (Adenosine triphosphate). ATP is the “energy currency” of a cell and the cells utilize ATP to carry out several functions, including cell division. Because the mitochondria are found in the cytoplasm, the embryo gets all its mitochondria from the mother - from the oocyte cytoplasm. The mitochondria from the sperm are immediately degraded after fertilization. When eggs from a woman of advanced maternal age are used to form embryos, there is a higher possibility that these mitochondria are genetically or functionally defective (as a result of aging !) Such defects compromise their function, including ATP production, as a result of which the embryo might not get enough energy to carry out its cell division , and will eventually stop dividing. This kind of mitochondrial dysfunction of oocyte has been proposed as one of the causes of developmental arrest. It has been shown that when the cytoplasm ( which contains the mitochondria ) from the oocyte of young women is transferred to the oocyte of older women (cytoplasmic transfer) , the developmental capability of the embryos was restored. Such kind of cytoplasmic transfer is being used to treat certain forms of infertility, leading to live births; but their efficacy and safety is yet to be appropriately investigated !

Once you find out your embryos have arrested in vitro, can anything be done to revive them  ? Sadly, the answer is no.  The arrest is irreversible and these embryos cannot be rescued. The important thing is to document this; and learn from it, so you can improve your chances of success in your next cycle.

If you are an older woman who has experienced developmental arrest of your embryos, donor oocytes can be a very good alternate option to have a baby. If you are young, and if you were informed that all your embryos have arrested, you should consider changing the IVF clinic. If this situation repeats itself, cytoplasmic transfer is one treatment option which you could explore; but this treatment is still in its infancy, and is not practised widely. If you are undergoing IVF, you should be aware that a very small percentage of your embryos can arrest during their development in IVF lab, and this is quite normal. 

You should always ask your IVF clinic to provide you with photos of your embryos ! You can see what embryos should look like at www.drmalpani.com/embryos.htm

The bitter truth is that during IVF, not all the eggs can be fertilized; not all the embryos which are formed will be good enough to be transferred to the uterus; and not all the embryos which are transferred to the uterus will develop into a baby. Which embryo will become a healthy baby is a million dollar question, and hopefully in the near future, with the help of scientific advances, we will be able to pin point that single “good embryo” which will grow into the much desired baby. Until then it is wise to remember this – “all babies come from embryos but not all embryos can become babies” !

Do’s and don’ts during 2ww

Do’s

• Take your medicines properly.
• Continue with your everyday normal activity.
• Surround yourself with people who will make you feel relaxed and happy.
• Do not do anything which you are not comfortable with. This will help to avoid self-blame if the IVF cycle did not succeed.

Dont’s

• Do not use sauna, hot tubs ( you can have showers !) or do any vigorous activity (like strenuous exercise)  which could raise your basal body temperature.
• Don’t change your diet drastically.
• Do not restrict your daily activity-do not take bed rest !
• Do not raise your hopes too much – have realistic expectations !
• Avoid people who can raise your insecurity and stress levels.

Read more at : http://blog.drmalpani.com/2010/09/what-precautions-should-i-take-after.html

http://blog.drmalpani.com/2012/01/dos-and-donts-during-ivf-2-ww.html

I have failed IVF repeatedly, what should I do ?

You can do five things :

• Change your IVF clinic
• Change the egg
• Change the uterus
• Change the sperm
• Change the embryo

Unfortunately, there are no clear answers for most failed IVFs. If you have undergone multiple failed IVFs , these are the options you have in front of you :

• If you are a woman of advanced maternal age or with premature ovarian failure, it would be reasonable to try IVF with donor eggs from a young woman. In most cases this will solve the problem.
• If you are young and have still encountered several failed IVFs, try changing the clinic. However, make sure the doctor does not mechanically repeat the same treatment
• If you are obese and have metabolic disorders like PCOD or diabetes, try reducing your weight and keep your insulin and glucose levels under control and try again.
• If the above solutions do not solve your problem , then you can consider surrogacy.
• If fertilisation is occurring, then using donor sperm is unlikely to help, because 90% of the genetic abnormalities which prevent embryo development and implantation are found to arise from the egg , and not from the sperm.
• If you are unsure whether there is problem with your egg or your husband’s sperm , you can opt for donor embryos.

There is no explanation why IVF does not work for some women. Be open to different treatment options (like donor eggs or surrogacy); and if not, then have a plan B (like adoption or child-free living). Never start an IVF cycle with the notion that I will succeed. It is wiser  to start with the question “What will I do if my IVF cycle does not succeed ?”. Having such a mind-set will help you to remain resilient and sane.

Read  more at : http://www.drmalpani.com/failedivf.htm

http://blog.drmalpani.com/2010/06/after-4-failed-ivf-cycles-what-should-i.html

http://blog.drmalpani.com/2011/02/i-have-failed-five-ivf-cycles-dr.html

If I have repeated implantation failure, does this mean my uterus is defective ? Should I opt for surrogacy ?

When women go through a couple of failed IVF cycles, the first doubt that comes to their mind is – is my uterus defective ? Is it rejecting my beautiful embryos ?  They start believing that implantation is not occurring because their uterus is defective . Their doubt appears very logical , because they can see that their embryos are growing well and are of Grade A quality .  When the doctor says  - Your embryos look beautiful and you have a very good chance of getting pregnant ( something most IVF doctor will say at the time of transfer, when they create good quality embryos in the lab), they start thinking that they are definitely going to get pregnant. When these beautiful embryos fail to implant, they start doubting the ability of their uterus to sustain a pregnancy. It is true that the uterus plays an important role in implantation , but not as much as the embryo does. When you develop a good endometrial lining and if your uterus does not have any gross abnormalities , it normally functions very well, no matter how old you are . However, even Grade A blastocysts which look perfect under the microscope can carry genetic defects which prevent them from implanting successfully.  This means that when both the embryos and the uterus appear perfect, it’s statistically much more likely that the embryo will be defective, as compared to the uterus. Let’s think about this logically. If all perfect embryos were to implant , then why does only one out of the 2 or 3 Grade A embryos which are transferred into a receptive uterus implant ? Why don’t all of them implant and give rise to multiple pregnancies ? If it was endometrial receptivity which played the major rate limiting factor in implantation , then all the Grade A embryos that are transferred to a women who gets pregnant in a particular cycle would have implanted ! The fact that only some of the Grade A embryos implant even in a successful cycle shows that it is the competency of the embryo which plays a major role in achieving implantation – not the uterus.  Even when you go through multiple implantation failures, there is a greater possibility that it is your embryos that are genetically defective , rather than your uterus. This is especially true if you are a women of advanced maternal age or have poor ovarian reserve. This is why older women get pregnant so easily with donor eggs, while they fail to achieve a pregnancy with their own eggs ! So if your uterine  cavity is normal , and if it develops a good endometrial layer, it is wise not to opt for surrogacy. Surrogacy is a good solution only for the very small minority of women whose uterus is damaged or absent. Unfortunately, the innocent uterus is blamed all the time when a couple faces infertility . “She is barren” on “In her uterus nothing grows, not even worms” - these are some of the hurting barbs directed against infertile women - and these break her  confidence in the ability of her uterus to carry a baby !

Can’t we tackle this problem by checking the embryos before transferring them ? Unfortunately, there are no fool proof ways of selecting embryos which are genetically normal as of now; but recent scientific discoveries like “comprehensive chromosome screening (CCS)” appear promising.

Read more at : http://www.drmalpani.com/solution_for_repeated_implantation_failure.htm

How many embryos should I transfer to optimize my chance of success ?

This decision depends on several factors :

1. Your age
2. the quantity of eggs retrieved from you
3. the quantity and quality of embryos that were formed
4. The age of your embryo at the time of transfer (day 3 transfer or day 5 transfer)
5. How many IVF cycles you have failed previously
6. Your risk taking appetite
7. The laws that govern Assited Reproductive Technology (ART) in your country

Read more at : http://blog.drmalpani.com/2010/10/how-do-we-decide-how-many-embryos-to.html

Even though transferring more embryos seems a logical way to achieve success quicker, the risk associated with multiple pregnancy should not be neglected. The goal of any particular IVF cycle should be to produce a healthy baby !

Why did my eggs fail to fertilize ? (complete fertilization failure)

This is another heart-breaking situation which some couples face when they go through IVF. You are very anxious to know the day after egg collection as to how many of your eggs have fertilizedand how many embryos you have ! But there are some rare instances where none of your  eggs fertilises and you are left with no embryos to transfer. The reasons for complete fertilization failure include :

•  Lab error - technical problems in the embryology lab , such as infection in the culture medium or an incubator malfunction can cause this

• Sperm problems  –  Sometimes even normal looking sperms can fail to fertilize the eggs.  This kind of fertilization failure due to functionally incompetent sperm can be prevented by using ICSI (a technique where a sperm is directly injected into egg , thus facilitating fertilization).  If ICSI fail to solve the problem then the issue lies most probably with the egg and not with the sperm.  This is because once the sperm enters the egg , the further events that take place are controlled by the egg’s machinery , and not by the sperm’s !
• Egg problems

What do you do when faced with such a situation ? This is a medical emergency !

• Ask the embryologist whether there was a lab problem. However, even if there was, it’s quite likely that the lab is not going to be completely honest about this. If only your eggs failed to fertilize on the particular day,  while the eggs of the other patients fertilised normally, the chances of a lab error are low.
• Ask the embryologist to do rescue ICSI. Here the embryologist injects a sperm into the unfertilized egg . While the success rate is low, this can help to salvage the cycle; and will also prove that the problem was with the sperm and not with the egg
• Try again in another clinic – this gives you a better chance of pinpointing where the problem lies!

Read more at : http://blog.drmalpani.com/2010/10/failed-fertilisation-after-ivf.html

I got no eggs during egg collection – what went wrong ? Why were my follicles empty ?

There are some women who face this difficult situation when undergoing IVF. They take all their injections, their ovaries grow lots of follicles, and their estrogen level in the blood rises as it should - but on the day of egg collection , the doctor cannot retrieve any eggs from their follicles ! This is called Empty Follicle Syndrome (EFS) and can be heart-breaking for a patient. Why does this happen ?

•  The hCG injection which is given to mature the follicles ( the “trigger shot”) was not taken at the right time. The follicles attain maturity 36 hours after taking the hCG injection. If the hCG is taken too early, the patient can ovulate her eggs before they can be collected. If the patient has taken the hCG shot too late, the eggs are not mature and these immature eggs cannot be flushed out of the follicles. So please ask the clinic staff for the exact time you need to take your hCG injection. If you fail to take the hCG shot at the proper time , please inform your doctor. 

•  The hCG shot was not given properly. Some patients forget to dissolve the powder in the solvent – and take only the solvent – which is just sterile water ! This is not uncommon, because the HCG injection is often given in the middle of the night, when errors do occur. 

• If your egg collection gets delayed past the 39 hour mark, you might ovulate , as a result of which the eggs are no longer present in the follicle. 

• EFS can also be the result of an abnormality in the in-vivo biological activity of some batches of commercially available human chorionic gonadotrophin (HCG)

•  In very rare cases there is an entity called genuine empty follicle syndrome where no known cause can be identified

Read more at : http://blog.drmalpani.com/2012/08/empty-follicle-syndrome-efs-guide-for.html

http://blog.drmalpani.com/2012/12/why-you-may-not-get-eggs-during-your.html

Poor Ovarian Reserve

(A) Follicular dynamics and illustration of the folliculogenesis process in physiology. (B) The possible mechanisms generating POI may affect different stages of folliculogene © 2011 Society for Endocrinology
POI - Primary Ovarian Insufficiency or premature ovarian failure

What is poor ovarian reserve ?

Poor ovarian reserve or diminished ovarian reserve ( DOR) is a condition where the amount of eggs which have the potential to give rise to a healthy baby decline.  Most women develop poor ovarian reserve 6 to 8 years before reaching menopause. As women age, their ovarian reserve declines too. But there are some women who develop diminished ovarian reserve much earlier in their reproductive period and their ovarian age does not match their calendar age . In 90% of cases there is no explanation (idiopathic) why such premature ovarian aging happens.  But there are a few explanations for premature ovarian aging . These include :

• Mutation in genes which codes for proteins that are involved in reproductive function
• Autoimmune disorders
• Certain viral infections
• Chemotherapy or radiation exposure during cancer treatment
• Surgery on the ovaries to remove cyst , or to remove endometriosis implants

Read more at : http://blog.drmalpani.com/2010/04/poor-ovarian-reserve-as-cause-of.html

http://www.drmalpani.com/ovarianreserve.htm

How will I know whether I have poor ovarian reserve ?

There are three important tests which are routinely used in the field of ART for predicting a woman’s ovarian reserve :

1)      Measuring Anti-Müllerian Hormone levels (AMH) in blood

2)      Measuring FSH levels in blood

3)      Counting antral follicles (AFC count) present in your ovaries using vaginal ultrasound

Read more at : http://www.drmalpani.com/ovarianreserve.htm

These are very simple tests to perform and the information they provide is pretty accurate.  

How does poor ovarian reserve compromise IVF success ?

• Women with poor ovarian reserve have fewer antral follicles in their ovaries. Antral follicles are the ones which grow in response to ovarian stimulation. This is why they produce fewer eggs when their ovaries are stimulated with gonodotropins (FSH and LH), which reduces their chances of IVF success .
• Older women with poor ovarian reserve have poorer egg quality too. Older eggs are more prone to genetic errors , like aneuploidy. Embryos formed from these eggs either fail to implant or fail to achieve a healthy pregnancy.

I am diagnosed with poor ovarian reserve , will I be able to have my genetic child ?

Women with poor ovarian reserve have a poor prognosis with IVF treatment. However, younger women who are diagnosed with poor ovarian reserve have a better chance of success than their older counterparts. This is because these younger women still produce some eggs which are of good genetic quality. This means they produce fewer eggs , but the quality of their eggs is comparable to women of their age. This improves their chances of achieving a pregnancy and carrying a baby to term is high too. 

If you are diagnosed with poor ovarian reserve, it is wise to try one IVF cycle by stimulating your own ovaries , before deciding what to do. Remember, the final proof of your ovarian reserve status depends on how well you respond to ovarian stimulation during IVF. There are women who have very good AMH levels, and yet they respond poorly to ovarian stimulation - and vice versa. Theoretically, as long as you produce eggs, you have a chance of achieving a pregnancy.  During your IVF cycle, if your doctor finds that even with maximal stimulation, you are unable to produce a decent amount of eggs ; and  if those eggs give rise to very poor quality embryos, you may want to consider the option of using donor eggs. This is a decision only you can make !