You know, a little more than 30 years ago, I was presented with some breathtaking information. No, not another invention or process. This was way more personal.
I found out that at my elevated age, I was about to become a father again. As I as processing this information (trust me- I was “flying high”- but also discerning how two very busy professionals running enterprises that were about 11 digits in volume would be able to devote sufficient time for this new addition), I was also listening to two sets of friends who were desperate to have their first.
These folks were relying on a very new process. IVF- in vitro fertilization. The cost for this process was sky high. (It actually was equal to the annual wages of one of the couples.) But, it gave them some hope.
Well, hope isn’t always reality. It seems that there were abnormalities in the embryos. After examining the shape and structure- as well as encountering some (then very rudimentary) genetic screens- the centers wouldn’t even consider implanting the cells.
That’s pretty much how things have been for decades. Except…
We now know that if only a small portion of the cells have chromosomal abnormalities (these are known as “mosaic embryos”), we shouldn’t be so quick at discarding them. That means about a 25% increase in the number of embryos that can be used for implantation.
The first “proof”?
Ms. Andria Besser, Director of Reproductive Genetics at NYU Langone Health, along with her two colleagues Amy Paul and Dr. James Grifo, presented findings from 35 implanted mosaic embryos over the course of 6 years , at the 2021 American Society for Reproductive Medicine in Baltimore (20 October 2021). The poster presentation was entitled: Results of Prenatal Diagnosis after Mosaic Embryo Transfer Indicate Low Risk of Fetal Chromosome Abnormality. [Note that Ms. Besser also headed up a Roundtable Discussion, How to Interpret Embryo Mosaicism and to Counsel PGT (RAA: that means PreImplanting Genetic Testing) Patients for Transferring Mosaic Embryos.]
The Second?
Dr. Antonio Capalbo (along with Drs. M. Poli, P.E.L. Setti, L. Girardi, D. Cimadomo, F. Benini, C. Rubio, L. Sacchi, C. Livi, F.M. Ubaldi, and C. Simon, plus Ms. E Albani and C. Pattasini, and L.F. Rienzi) of Igenomix (a genetic testing company) led another study. The title: Newborns Derived from Embryos Showing Low/Moderate-Degree Mosaicism Do Not Exhibit Chromosomal Aberrations or Uniparental Disomy Profiles.
The study examined some 897 embryo transfers effected via IVF. About ½ (484) were normal embryos, almost 1/3 (282) involved low-level embryos, with the rest (131) were moderate level mosaic embryos.
What’s the difference between low-level and moderate level? Low level was defined as such if 20-30% of the cells in the embryo had abnormal numbers of chromosomes; it was elevated to moderate level was the abnormalities ranged from 30 to 50%.
The good news? Both types of mosaic embryos had the same chance of implantation as did the chromosomally normal embryos. More importantly, 42% of each class led to successful baby births. Oh- with no genetic abnormalities.
Now, we have to wonder why such results manifested. The first postulate is that mosaic embryos have a means to eradicate abnormal cells during development. The more logical postulate is that genetic testing of the embryos identify mosaics that may not be truly so. After all, only a small sliver of DNA from the cells surrounding the embryo are extracted for samples- and these are probably not representative of the embryonic chromosomal status.
While both postulates need to be verified, the authors of both papers are more comfortable with the second concept. (Especially in light of the studies effected by Genomic Prediction [Nathan Treff and Diego Marin] of some 2700 mosaic IVF embryo transfers- where only 1 baby resulted in mosaicism, which was mild and didn’t affect the child’s health.)
This is great news for the 2/3 of IVF prospects that have routinely elected not to proceed with these embryos, since they were warned of the (now seemingly incorrect) risks of such implantation. (Not to mention that 1/3 of the US clinics that wouldn’t proceed with such implantation.)
Amazingly- there’s an article in today’s Washington Post describing other issues with IVF (also called ART- assisted reproductive technology)
https://www.washingtonpost.com/health/ivf-fertility-treatments-cost-success/2021/11/12/3eaaa4f0-26db-11ec-8d53-67cfb452aa60_story.html
You’d think implanting an abnormal embryo would be a No-No. Yet somehow they transform into normalcy . Wonders never cease!
That’s what drew me to this research, Kate.
This is interesting — I guess I didn’t realize that it was a significant problem in IVF.
But this is a weird subject for me as someone with a daughter with Down Syndrome (naturally no assistance), it’s always difficult to read about genetic issues with embryos. As a doctor, I understand and know the reasons, but as a mom, I feel sad.
Thank you for sharing!
Dominique recently posted..Tips for Thanksgiving Vegetable Sides
Yes, there are no guarantees. Thanks for adding to the discussion, Dominique.
Our older granddaughter (early 30’s) and her husband were about to look into tht when a mircale happened and it wasn’t needed.
Martha recently posted..It’s Chili
Ah! Wonderful how those miracles arrive, Martha.
Fortunate enough not to ever needed IVF, the concept of mosaic embryos was new to me. Having known women over the years who suffered from either infertility or the inability to bring a pregnancy to term (when one friend finally became pregnant in a last gasp effort and nearly died from a tubular pregnancy – she ended up adopting) this is hopeful news indeed.
Alana recently posted..Imperfect Pandemic Crochet
One can only hope that studies like this can make the costs lower and the successes higher.
Wow! What a great post. My sister-in-law had twin girls in vitro. I had trouble getting pregnant and had one miscarriage, so this topic is dear to my heart. Thanks for writing about a tender subject to many couples who despair over not getting pregnant easily.
Larada Horner-Miller recently posted..Are You a Homemaker? More Poetry
I thought this information should spread as wideely as possible, Larada.
this is certainly positive news for the many people for whom IVF is the only option.. I know many friends who went through the process and it was certainly a long one..
vidya recently posted..Great YA Books You Need to Read
I’m with you, Vidya!