PGT-SR – structural rearrangements diagnosis

Luca Gianaroli, MD
Specialist in Reproductive Medicine & Scientific Director

Genetics PGS / PGT-A

From this video you will find out:
  • What is PGT-SR (Preimplantation Genetic Testing for Chromosomal Structural Rearrangements)?
  • Who is PGT-SR for?
  • How is this procedure performed?
  • What types of translocations are there?
  • What is a chromosomal structural rearrangement?
  • How to find out if one is a carrier of a structural rearrangement?
  • Which diseases can be caused by parental structural rearrangement?
  • Is there a correlation between structural rearrangements and infertility?

What is PGT-SR testing?

In this webinar, Dr Luca Gianaroli, MD, Scientific Director of S.I.S.Me.R (Italian Society for the Study of Reproductive Medicine) has explained PGT-SR,  preimplantation genetic testing for chromosomal structural rearrangements, how it’s done, indications and how it can improve the chance of a healthy pregnancy.

- Questions and Answers

Are the embryos harmed by freezing and thawing?

No,  even if there is a variability that’s changed from patient to patients. The survival rate and the viability rate of frozen-thawed embryos after biopsy vary between 98 to 100% of viability. The risk of losing the embryo is extremely limited, as far as the right technique is used and, in this case, the vitrification technique.

Do translocations in sperm or oocyte affect fertilization rate or embryo development during IVF/ICSI?

Not fertilization because most of the time, when you’re using ICSI, you just force fertilization. The problem is that in some translocations, these embryos have not enough energy. If they are generated by unbalanced gametes, they don’t have enough resources to normally develop. These embryos do not develop properly. So, no for fertilization, potentially yes for their development.

Is it true that you need to retrieve more eggs when planning treatment with PGT-SR/PGT-M and why?

For a very simple reason because you know in advance that a percentage of these eggs that even if they fertilize or even if they develop an embryo, they will not be transferable. You need more eggs to have more embryos to choose from a larger basket of embryos, those that will be suitable for transfer.

What do you do when the trophectoderm biopsy reveals mosaicism? Do you do the transfer?

All in all, it’s quite a complicated question because it depends on the type of mosaicism, it depends on the percentage of mosaicism. What is interesting is that if you use some technique, you don’t see the mosaicism, you only see if they are euploid or aneuploid, they are black and white.

If you use more sophisticated techniques, then you can see mosaicism. Then there is a sort of degree of risk that you can take in transferring embryos that are mosaic according to their percentage and chromosomes that are involved.

After how many failed IVF cycles would you recommend sperm and/or egg donation?

It depends on what you mean by failure. If you mean no embryo development, so no embryo transfer, I would not go for it if you are a poor responder over two cycles. If you are a poor responder, you can also wait for a third cycle. If by the failure you mean a biochemical pregnancy or a miscarriage, then you don’t need to stop IVF but to go for PGT for an aneuploidy, of course, this implies first perform the chromosomal analysis in both partners.

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Luca Gianaroli, MD

Luca Gianaroli, MD

Dr Luca Gianaroli has been a specialist in Reproductive Medicine since the end of the 1970s. He is the Scientific Director of S.I.S.Me.R. (Italian Society for the Study of Reproductive Medicine) and he holds the position of Scientific Director of I.I.A.R.G., the International Institutes of Advanced Reproduction and Genetics and of IIRM SA. He is also an Honorary Professor at the School of Biosciences of the University of Kent. Dr Gianaroli is an active member of several international scientific societies in which he has covered and currently covers roles of primary importance, he has served as Chairman of the Italian Society of Reproduction and of the European Society of Human Reproduction and Embryology (ESHRE). He is a member of the ESHRE Certification Committee, and he is the coordinator of the Steering Committee of the ESHRE ART Centre Certification Program. Dr Gianaroli is author of more than 250 papers in international scientific journals and publisher or co-publisher of 9 books. Throughout his professional career, he collaborated with several Italian universities (Università degli Studi di Teramo, Università degli Studi di Modena e Reggio Emilia, Università degli Studi di Trieste, Università degli Studi di Roma Tor Vergata, Università di Bologna).
Event Moderator
Caroline Kulczycka

Caroline Kulczycka

Caroline Kulczycka is managing MyIVFAnswers.com and has been hosting IVFWEBINARS dedicated to patients struggling with infertility since 2020. She's highly motivated and believes that educating patients so that they can make informed decisions is essential in their IVF journey. In the past, she has been working as an International Patient Coordinator, where she was helping and directing patients on their right path. She also worked in the tourism industry, and dealt with international customers on a daily basis, including working abroad. In her free time, you’ll find her travelling, biking, learning new things, or spending time outdoors.
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