Ask Our Doctors – Archive
Our Medical Directors are outstanding physicians that you will find to be very personable and compassionate, who take care to ensure that you have the most cutting-edge fertility treatments at your disposal. This is your outlet to ask your questions to the doctors.
Hello Dr. Sher,
I’m writing in response to your blog, “Embryo Mosaicism: What You Need to Know”. I submitted a comment and received an email that there was a glitch and I should post here instead.
I have had 3 IVF retrievals and only 2 embryos have reached blast and been tested. One was abnormal and the other high level mosaic. We are willing to accept above average risk of miscarriage, but we are not comfortable with significantly above average risk of disability (and might not be open to terminating a pregnancy). Based on that, would you personally recommend transferring the mosaic (Embryo # 2, below) or discarding it? Does a -21 mosaic carry higher than normal risk of Down’s?
Embryo #1: Aneuploid -15,dup(21) (pter-q22.11)[mos
Embryo #2: High Level Mosaic +11 [mos], -21 [mos]
Thank you for sharing your expertise so generously with so many prospective parents,
Jillian
Although unlikely, the possibility of a disabled baby cannot be excluded with surity.
Geoff Sher
While highly unlikely that should a pregnancy occur there would be a disability…this cannot be guaranteed!
Dr. Sher, thank you so much for responding so quickly. In my case the eggs were purchased from an egg bank and both women were in their 20’s. With the 2nd lot of cohorts we did PGS and identified the gender/chromosomes of the 2 good embryos. I am a very healthy 55 year old and had my 1st child at 51! However, even with getting the eggs from a bank earlier and now considering purchasing Embryos, do you think age is the detrimental factor in getting pregnant in my case? I am happy to do a skype consult with you if you think it might help! Thanks!
Your age does make pregnancy a more hazardous undertaking but it should not markedly affect your ability to conceive with egg donation.
I think we should talk!
Geoff Sher
Dear Dr. Sher, I watched your visit in the Egg whisperer show and I really got curious about all your knowledge regarding implementation failure.
I’m a 33 year old woman who suffers from unexplained infertility. In 2019 I got naturally pregnant one month after stopping the birth control pill. Unfortunately I has a missed abortion around week 8 which had to be removed by surgery. For one year after that nothing happened and we asked for fertility help. In oktober 2020 I got pregnant with twins in the first IUI-H attempt. Unfortunately I suddenly got into labour in week 22+3 and we still don’t know why. At first the doctors explanation was that it is just risky with a twin pregnancy and then they thought I might had a bicornuate uterus. Later I got a mini-hysteroscopy that showed only slightly bicornuate uterus but nothing that they would correct in surgery.
8 weeks after I gave birth to the twins we found out that the entire placenta was not out yet so I had to undergo two surgeries. Two weeks after the last surgery I got the mini-hysterescopy that showed that everything looked normal.
Now the fertility clinic have suggested IVF to avoid a twin pregnancy. I have now had four egg retrievals with 5 transfers without a positive result. First egg retrieval = 4 eggs but only 1 made it to blastocyst, second attempt= 18 eggs (I had to wait for a frozen embryo transfer due to overstimulation) 1 egg made it for the freezer, third attempt= 10 eggs, 1 transferred in fresh cycle and 1 in frozen but this one didn’t make the thawing that well but we transferred it anyway and now the fourth attempt = 4 eggs, 1 7-cell embryo was transferred at day 3.
In my eyes it seem like my egg quality is suddenly very bad. My husband have really good sperm quality and normally almost all my eggs will be fertilised but they will not make it to day 5.
So my question is if there is anything I should ask the doctor to check before having the last egg retrieval in this clinic? I just can’t understand what is changed from when I got pregnant naturally and when I got pregnant with even two eggs and until now when the blastocysts will not implement in my uterus?
In august 2021 my AMH was 7,3 pmol/L
Thank you so much in advance!
P.S. If I win the lottery I will travel all the way from Denmark to you and let you help us in becoming parents of a healthy baby 🙂
Dear Dr Sher, I got your name and blog details from Alena at Embryo Adoption. We got eggs from Fairfax egg bank in 2017 where we had 2 good embryos created with my husbands sperm. The first transfer was successful and we have a wonderful 4 year old. We have been trying to have a baby so he can have a sibling. The 2nd transfer from that cohort gave me a chemical pregnancy and did not work. We again got a 2nd lot of cohorts from the same bank and had 2 good embryos. But both transfers were unsuccessful. Before my last transfer on April 19th, the clinic had me do an ERA test which would give an idea of the time to start the progesterone/endometrin before the transfer and an Endometrial Receptivity Test. I was told there was no inflammation of the uterus after that test was done. My fertility doctor kept telling me I have the best uterine lining of all her patients and am the healthiest and the fittest of them. I believe my lining was at 9mm. She is at a loss to explain why the embryos could not implant. I have been on thyroid medication and prenatals with DHEA the whole time. Alena mentioned that in her case she was taking dexamethasone and it might help in my case. Any insight would be wonderful. Thank you!
Whenever a patient fails to achieve a viable pregnancy following embryo transfer (ET), the first question asked is why! Was it simply due to, bad luck?, How likely is the failure to recur in future attempts and what can be done differently, to avoid it happening next time?.
It is an indisputable fact that any IVF procedure is at least as likely to fail as it is to succeed. Thus when it comes to outcome, luck is an undeniable factor. Notwithstanding, it is incumbent upon the treating physician to carefully consider and address the causes of IVF failure before proceeding to another attempt:
1.Age: The chance of a woman under 35Y of age having a baby per embryo transfer is about 35-40%. From there it declines progressively to under 5% by the time she reaches her mid-forties. This is largely due to declining chromosomal integrity of the eggs with advancing age…”a wear and tear effect” on eggs that are in the ovaries from birth.
2.Embryo Quality/”competency (capable of propagating a viable pregnancy)”. As stated, the woman’s age plays a big role in determining egg/embryo quality/”competency”. This having been said, aside from age the protocol used for controlled ovarian stimulation (COS) is the next most important factor. It is especially important when it comes to older women, and women with diminished ovarian reserve (DOR) where it becomes essential to be aggressive, and to customize and individualize the ovarian stimulation protocol.
We used to believe that the uterine environment is more beneficial to embryo development than is the incubator/petri dish and that accordingly, the earlier on in development that embryos are transferred to the uterus, the better. To achieve this goal, we used to select embryos for transfer based upon their day two or microscopic appearance (“grade”). But we have since learned that the further an embryo has advanced in its development, the more likely it is to be “competent” and that embryos failing to reach the expanded blastocyst stage within 5-6 days of being fertilized are almost invariably “incompetent” and are unworthy of being transferred. Moreover, the introduction into clinical practice about 15y ago, (by Levent Keskintepe PhD and myself) of Preimplantation Genetic Sampling (PGS), which assesses for the presence of all the embryos chromosomes (complete chromosomal karyotyping), provides another tool by which to select the most “competent” embryos for transfer. This methodology has selective benefit when it comes to older women, women with DOR, cases of unexplained repeated IVF failure and women who experience recurrent pregnancy loss (RPL).
3.The number of the embryos transferred: Most patients believe that the more embryos transferred the greater the chance of success. To some extent this might be true, but if the problem lies with the use of a suboptimal COS protocol, transferring more embryos at a time won’t improve the chance of success. Nor will the transfer of a greater number of embryos solve an underlying embryo implantation dysfunction (anatomical molecular or immunologic).Moreover, the transfer of multiple embryos, should they implant, can and all too often does result in triplets or greater (high order multiples) which increases the incidence of maternal pregnancy-induced complications and of premature delivery with its serious risks to the newborn. It is for this reason that I rarely recommend the transfer of more than 2 embryos at a time and am moving in the direction of advising single embryo transfers …especially when it comes to transferring embryos derived through the fertilization of eggs from young women.
4.Implantation Dysfunction (ID): Implantation dysfunction is a very common (often overlooked) cause of “unexplained” IVF failure. This is especially the case in young ovulating women who have normal ovarian reserve and have fertile partners. Failure to identify, typify, and address such issues is, in my opinion, an unfortunate and relatively common cause of repeated IVF failure in such women. Common sense dictates that if ultrasound guided embryo transfer is performed competently and yet repeated IVF attempts fail to propagate a viable pregnancy, implantation dysfunction must be seriously considered. Yet ID is probably the most overlooked factor. The most common causes of implantation dysfunction are:
a.A“ thin uterine lining”
b.A uterus with surface lesions in the cavity (polyps, fibroids, scar tissue)
c.Immunologic implantation dysfunction (IID)
d.Endocrine/molecular endometrial receptivity issues
e.Ureaplasma Urealyticum (UU) Infection of cervical mucous and the endometrial lining of the uterus, can sometimes present as unexplained early pregnancy loss or unexplained failure following intrauterine insemination or IVF. The infection can also occur in the man, (prostatitis) and thus can go back and forth between partners, with sexual intercourse. This is the reason why both partners must be tested and if positive, should be treated contemporaneously.
Certain causes of infertility are repetitive and thus cannot readily be reversed. Examples include advanced age of the woman severe male infertility immunologic infertility associated with alloimmune implantation dysfunction (especially if it is a “complete DQ alpha genetic match between partners plus uterine natural killer cell activation (NKa).
Would you consider transferring aneuploid embryos of a (trisomy 13) and a (trisomy5- monosomy22).
Thank you
That depends on many additional considerations!
See below!
What is it and Human embryo development occurs through a process that encompasses reprogramming, sequential cleavage divisions and mitotic chromosome segregation and embryonic genome activation. Chromosomal abnormalities may arise during germ cell and/or preimplantation embryo development and represents a major cause of early pregnancy loss. More than 15 years ago, we were the first to introduce full embryo karyotyping (identification of all 46 chromosomes) through preimplantation genetic sampling (PGS) as a method by which to selectively transfer only euploid embryos (i.e. those that have a full component of chromosomes) to the uterus. We subsequently reported on a 2-3-fold improvement in implantation and birth rates as well as a significant reduction in early pregnancy loss, following IVF. Since then PGS has grown dramatically in popularity such that it is now widely used throughout the world.
Many IVF programs that offer PGS/PGT-A services, require that all participating patients consent to all their aneuploid embryos (i.e. those with an irregular quota of chromosomes) be disposed of. However, a growing body of evidence suggests that following embryo transfer, some aneuploid embryos will in the process of ongoing development, convert to the euploid state (i.e. “autocorrect”) and then go on to develop into chromosomally normal offspring. In fact, I am personally aware of several such cases having occurred in my own practice. So clearly, summarily discarding all aneuploid embryos as a matter of routine we are sometimes destroying some embryos that might otherwise have “autocorrected” and gone on to develop into normal offspring. Thus, by discarding aneuploid embryos the possibility exists that we could be denying some women the opportunity of having a baby. This creates a major ethical and moral dilemma for those of us that provide the option of PGS/PGT-A to our patients. On the one hand, we strive “to avoid knowingly doing harm” (the Hippocratic Oath) and as such would prefer to avoid or minimize the risk of miscarriage and/or chromosomal birth defects and on the other hand we would not wish to deny patients with aneuploid embryos, the opportunity to have a baby.
The basis for such embryo “autocorrection” lies in the fact that some embryos found through PGS/PGT-A-karyotyping to harbor one or more aneuploid cells (blastomeres) will often also harbor chromosomally normal (euploid) cells (blastomeres). The coexistence of both aneuploid and euploid cells coexisting in the same embryo is referred to as “mosaicism.”
It is against this background, that an ever-increasing number of IVF practitioners, rather than summarily discard PGS-identified aneuploid embryos are now choosing to cryobanking (freeze-store) certain of them, to leave open the possibility of ultimately transferring them to the uterus. In order to best understand the complexity of the factors involved in such decision making, it is essential to understand the causes of embryo aneuploidy of which there are two varieties:
1.Meiotic aneuploidy” results from aberrations in chromosomal numerical configuration that originate in either the egg (most commonly) and/or in sperm, during preconceptual maturational division (meiosis). Since meiosis occurs in the pre-fertilized egg or in and sperm, it follows that when aneuploidy occurs due to defective meiosis, all subsequent cells in the developing embryo/blastocyst/conceptus inevitably will be aneuploid, precluding subsequent “autocorrection”. Meiotic aneuploidy will thus invariably be perpetuated in all the cells of the embryo as they replicate. It is a permanent phenomenon and is irreversible. All embryos so affected are thus fatally damaged. Most will fail to implant and those that do implant will either be lost in early pregnancy or develop into chromosomally defective offspring (e.g. Down syndrome, Edward syndrome, Turner syndrome).
2.Mitotic aneuploidy (“Mosaicism”) occurs when following fertilization and subsequent cell replication (cleavage), some cells (blastomeres) of a meiotically normal (euploid) early embryo mutate and become aneuploid. This is referred to as “mosaicism”. Thereupon, with continued subsequent cell replication (mitosis) the chromosomal make-up (karyotype) of the embryo might either comprise of predominantly aneuploid cells or euploid cells. The subsequent viability or competency of the conceptus will thereupon depend on whether euploid or aneuploid cells predominate. If in such mosaic embryos aneuploid cells predominate, the embryo will be “incompetent”). If (as is frequently the case) euploid cells prevail, the mosaic embryo will likely be “competent” and capable of propagating a normal conceptus.
Since some mitotically aneuploid (“mosaic”) embryos can, and indeed do “autocorrect’ while meiotically aneuploid embryos cannot, it follows that an ability to reliably differentiate between these two varieties of aneuploidy would potentially be of considerable clinical value. The recent introduction of a variety of preimplantation genetic screening (PGS) known as next generation gene sequencing (NGS) has vastly improved the ability to reliably and accurately karyotype embryos and thus to diagnose embryo “mosaicism”.
Most complex aneuploidies are meiotic in origin and will thus almost invariably fail to propagate viable pregnancies. The ability of mosaic embryos to autocorrect is influenced by stage of embryo development in which the diagnosis is made, which chromosomes are affected, whether the aneuploidy involves a single chromosome (simple) or involves 3 or more chromosomes (complex), and the percentage of cells that are aneuploid. Many embryos diagnosed as being mosaic prior to their development into blastocysts (in the cleaved state), subsequently undergo autocorrection to the euploid state (normal numerical chromosomal configuration) as they develop to blastocysts in the Petri dish. This is one reason why “mosaicism” is more commonly detected in early embryos than in blastocysts. Embryos with segmental mosaic aneuploidies, i.e. the addition (duplication) or subtraction (deletion), are also more likely to autocorrect. Finally, the lower the percentage of mitotically aneuploid (mosaic) cells in the blastocyst the greater the propensity for autocorrection and propagation of chromosomally normal (euploid) offspring. A blastocyst with <30% mosaicism could yield a 30% likelihood of a healthy baby rate with 10-15% miscarriage rate, while with >50% mosaicism the baby rate is roughly halved and the miscarriage rate double.
As stated, the transfer of embryos with autosomal meiotic trisomy, will invariably result in failed implantation, early miscarriage or the birth of a defective child. Those with autosomal mitotic (“mosaic”) trisomies, while having the ability to autocorrect in-utero and result in the birth of a healthy baby can, depending on the percentage of mosaic (mitotically aneuploid) cells present, the number of aneuploid chromosomes and the type of mosaicism (single or segmental) either autocorrect and propagate a normal baby, result in failed implantation, miscarry or cause a birth defect (especially with trisomies 13, 18 or 21). This is why when it comes to giving consideration to transferring trisomic embryos, suspected of being “mosaic”, I advise patients to undergo prenatal genetic testing once pregnant and to be willing to undergo termination of pregnancy in the event of the baby being affected. Conversely, when it comes to meiotic autosomal monosomy, there is almost no chance of a viable pregnancy. in most cases implantation will fail to occur and if it does, the pregnancy will with rare exceptions, miscarry. “Mosaic” (mitotically aneuploid) autosomally monosomic embryos where a chromosome is missing), can and often will “autocorrect” in-utero and propagate a viable pregnancy. It is for this reason that I readily recommend the transfer of such embryos, while still (for safety’s sake) advising prenatal genetic testing in the event that a pregnancy results.
What should be done with “mosaic embryos? While the ability to identify “mosaicism” through karyotyping of embryos has vastly improved, it is far from being absolutely reliable. In fact, I personally have witnessed a number of healthy/normal babies born after the transfer of aneuploid embryos, previously reported on as revealing no evidence of “mosaicism”. However, the question arises as to which “mosaic” embryos are capable of autocorrecting in-utero and propagating viable pregnancies. Research suggests that that embryos with autosomal monosomy very rarely will propagate viable pregnancies. Thus, it is in my opinion virtually risk-free to transfer embryos with monosomies involving up to two (2) autosomes. The same applies to the transfer of trisomic embryos where up to 2 autosomes are involved. Only here, there is a risk of birth defects (e.g. trisomy 21/18, etc.) and any resulting pregnancies need to be carefully assessed and if needed/desired, be ended. Regardless, it is essential to make full disclosure to the patient (s), and to ensure the completion of a detailed informed consent agreement which would include a commitment by the patient (s) to undergo prenatal genetic testing (amniocentesis/CVS) aimed at excluding a chromosomal defect in the developing baby and/or a willingness to terminate the pregnancy should a serious birth defect be diagnosed. Blastocysts with aneuploidies involving > 2 autosomes are complex abnormal and should in my opinion, be discarded.
I strongly recommend that you visit http://www.SherIVF.com. Then go to my Blog and access the “search bar”. Type in the titles of any/all of the articles listed below, one by one. “Click” and you will immediately be taken to those you select. Please also take the time to post any questions or comments with the full expectation that I will (as always) respond promptly.
•A Fresh Look at the Indications for IVF
•The IVF Journey: The importance of “Planning the Trip” Before Taking the Ride”
•Controlled Ovarian Stimulation (COS) for IVF: Selecting the ideal protocol
•IVF: Factors Affecting Egg/Embryo “competency” during Controlled Ovarian Stimulation(COS)
•The Fundamental Requirements For Achieving Optimal IVF Success
•Use of GnRH Antagonists (Ganirelix/Cetrotide/Orgalutron) in IVF-Ovarian Stimulation Protocols.
•Anti Mullerian Hormone (AMH) Measurement to Assess Ovarian Reserve and Design the Optimal Protocol for Controlled Ovarian Stimulation (COS) in IVF.
•Controlled Ovarian Stimulation (COS) in Older women and Women who have Diminished Ovarian Reserve (DOR): A Rational Basis for Selecting a Stimulation Protocol
•Optimizing Response to Ovarian Stimulation in Women with Compromised Ovarian Response to Ovarian Stimulation: A Personal Approach.
•Hereditary Clotting Defects (Thrombophilia)
•Blastocyst Embryo Transfers done 5-6 Days Following Fertilization are Fast Replacing Earlier day 2-3 Transfers of Cleaved Embryos.
•Embryo Transfer Procedure: The “Holy Grail in IVF.
•Timing of ET: Transferring Blastocysts on Day 5-6 Post-Fertilization, Rather Than on Day 2-3 as Cleaved Embryos.
•IVF: Approach to Selecting the Best Embryos for Transfer to the Uterus.
•Fresh versus Frozen Embryo Transfers (FET) Enhance IVF Outcome
•Frozen Embryo Transfer (FET): A Rational Approach to Hormonal Preparation and How new Methodology is Impacting IVF.
•Staggered IVF
•Staggered IVF with PGS- Selection of “Competent” Embryos Greatly Enhances the Utility & Efficiency of IVF.
•Staggered IVF: An Excellent Option When. Advancing Age and Diminished Ovarian Reserve (DOR) Reduces IVF Success Rate
•Embryo Banking/Stockpiling: Slows the “Biological Clock” and offers a Selective Alternative to IVF-Egg Donation
•Preimplantation Genetic Testing (PGS) in IVF: It should be Used Selectively and NOT be Routine.
•IVF: Selecting the Best Quality Embryos to Transfer
•Preimplantation Genetic Sampling (PGS) Using: Next Generation Gene Sequencing (NGS): Method of Choice.
•PGS and Assessment of Egg/Embryo “competency”: How Method, Timing and Methodology Could Affect Reliability
•IVF outcome: How Does Advancing Age and Diminished Ovarian Reserve (DOR) Affect Egg/Embryo “Competency” and How Should the Problem be addressed.