PGS live birth rate per cycle started

[Dogpark]

Hi everyone. My clinic is recommending PGS to me and I just spoke to their embryologist to gather stats about this "add-on".

When talking about PGS, everybody at the clinic suddenly focuses on live birth rate per embryo transferred, which is about 50% in my age range, Vs 24% without PGS. Fair enough this looks interesting there. But when I force them to talk about live birth rate per cycle started, it's suddenly much lower than regular IVF (something like 10% vs 29% without PGS). I asked them why and they spent 20 minutes telling me that, you see, without PGS, more embryos are transferred so success rates are higher, and with PGS you don't have to transfer that many embryos. I kept on insisting that their live birth rate per cycle started looked bad to me, no matter how they cut it, and they finally said "oh that's because we recommend PGS to poorer prognosis patients to start with, like patients who have low amh". I asked them what the criteria was for this recommendation and they said "that's down to the consultant".

Has anybody else looked into these PGS stats? I feel like I am being served a lot of BS no matter how much I'd like PGS to work as a technology.

[MofM]

I have been discussing PGS with our consultant after a 6w+5 miscarriage of our only embryo. He said that PGS is perfect to understand whether an embryo is chromosomally normal, and does not have any major defect (e.g., large traslocation). However, he suggested that both my partner and I went for a karyotype, and do PGS only if one of us had some major issue, also to cut costs down.

I had a look into the scientific literature, and it seems that (guess what?) the effectiveness of embryo selection via PGS is not clear and that it has been observed that abnormal embryos go on developing in OK children. So it may be that if you did not do PGS you would have transfered an embryo which would have developed just fine, and therefore the drop in live birth *per cycle*.

On the other hand, it seems that PGS is a good way to prioritize embryo transfer, expecially if you have many of them. Using PGS you transfer the best ones first, and may save money and heartbreaking with subsequence frozen cycles, and therefore the increase in live birth *in general*.

As a consequence, I've also read the some consultants think that PGS it is better for young women (with many embryos that are likely normal, to prioritise transfer) rather than for old women (with few embryo which should be given a change to develop in utero).

Still, no one agrees, and we haven't decided what to do yet! Still waiting for my karyotype and understand how many promising embryos we would have...

[Fingerscrossed38]

I am pro PGS because I've had recurrent miscarriages and no luck getting pregnant in over a year. My consultant said it's highly likely the cause for these is chromosomal so why not eliminate the issue early on if we can?

I am 39 have good AMH and absolutely no issues with me or husband yet we are unexplained. So in order to eliminate abnormal embryos we decided to do pgs and not risk another miscarriage. I know it doesnt guarantee another miscarriage wont occur in the future but it it eliminates a pretty major reason and can help us concentrate on other areas if we are unsuccessful.

Yes, it's ridiculously expensive but I couldn't have another miscarriage and don't fancy playing Russian roulette anymore just to save money...each to their own though!

Luckily I've produced 6 normal blastocysts and they're safe in the freezer until we transfer one next cycle. It's our first round of IVF so still feeling positive.

Hopefully you come to a decision you're happy with. You can always try IVF without PGS and if you don't have any luck you can fall back on it then?

[Dogpark in reply to Fingerscrossed38]

Thank you for the replies MofM and Fingerscrossed38 . It's a tough call indeed. I would love to do PGS and get the exact same result as @Fingerscrossed38 (congrats!), then I would feel much better about transferring. But at my age, I may as well end up with no normal embryo, meaning that perhaps a normal embryo was discarded by the test.

I also agree with @MofM and read the same articles.

I already did one round of IVF, first transfer failed and now, I have 3 embryos frozen, but, again, due to age, I am going for another egg collection instead of transferring. I'll see how many embryos I get. If I get many, I might be tempted to do PGS, if not, why bother.

[Fingerscrossed38 in reply to Dogpark]

Have you read up on human growth hormone? I was worried mine would come back abnormal so was reading up on how to try to improve egg quality eggs some women did really well introducing HGH and DHEA...worth looking into perhaps?

[Hidden]

Hi Dogpark.

I am not sure if I understood exactly, but what really matters is the live birth per embryo transferred. I think the problem might be that if you didn't have any normal embryo after PGS in one cycle, you get no transfer. I mean, that doing PGS It happens that many cycles end up with no embryos to transfer. But I am sure this is also biased, in the sense that most of the time couples doing PGS are not the young ones with good numbers, if everybody was doing PGS there would be no bias and numbers would look more in favour of PGS. But for young couples most of the embryos would be chromosomically normal, so no point in doing PGS and there the bias!

Anyway, what you always have to think is that chromosomically abnormal embryos never end up giving normal babies and that they explain the majority of spontaneous miscarriages. There is only one viable abnormality that is Down syndrome (and probably if doing PGS you can opt to keep and transfer an embryo with down syndrome, I would say that's a personal choice as it could be viable). Everything else they can discover there would not be viable (implantation failures, early miscarriages, stillbirths or babies dying soon after birth, like sometimes patau and edwards syndromes that can survive birth). So I think PGS is a good choice specially if you have good numbers: you might reduce the number of embryos you have a lot, but increase a lot the chances of libre births (I would say even more than 50%, I have read 60-70%). You might also end with no embryos at all to transfer, but you are avoiding the emotional and physical trauma of a miscarriage...

Sorry that was a long answer!!!

All the best xxx

[Lizzielizzielizzie in reply to Hidden]

There’s more than one viable abnormal- Downs syndrome is the most common trisonomy but there are many more duplication/deletion syndromes which can be compatible with life but will usually lead to a child having additional needs. They don’t all have names.

[Hidden in reply to Lizzielizzielizzie]

Hi!

In terms of aneuploidies, only trisomy of 21 (Down) and changes in sexual chromosomes numbers are viable. Only two other aneuploidies are known to give sometimes living babies (most cases would lead to miscarriage), those of chromosomes 13 and 18 (Patau and Edwards). Anyway this last two are very serious and cause dead within a few months if born alive...

PGS only detects (this is different to PGD that is aimed at detecting specific and characterised changes) big changes in the genetic weight of each chromosome (aneuploidies and severe deletions or duplications). And yes, they could be viable but most certainly lead to babies with health conditions.

PGS is in some cases very well indicated, even finantially. A good friend of mine at age 40 still had very good numbers and produced several blastocysts. Two natural miscarriages. After 4 transfers all unsuccesful, they did another fresh cycle, produced 7 to freeze, these were PGS tested and the first transfer done with a normal embryo, ended up in their baby. If they had done it in the first instance they would have probably saved several failed trials... So It is true that it won't probably help much a young couple that are trying for the first time, for example, but I would say is very recommendable in some cases.

[Lizzielizzielizzie in reply to Hidden]

I’m sorry to argue but you are incorrect that only Down’s syndrome and changes to sex chromosomes are viable aneuploidies. What about crie du chat syndrome for starters? Caused by a deletion on chromosome 5, so not a trisonomy like downs, Edwards or patau but still a chromosome disorder. Or Wolf-Hirschhorn syndrome which is also a deletion? Not to mention all the duplication/deletion syndromes which are so rare that they don’t have a name. The website rarediseases.info.nih.gov/g... is helpful here if anyone would like to know more.

It’s important that people are aware of the correct information if choosing PGS. It is perfectly possible that with PGS you would be discarding viable embryos which, as you say, could have been living children although they would probably have special needs. One would need to decide where one stands morally on this and make sure you are comfortable with this. You would also need to question your clinic about their screening- maybe there are some clinics which only screen for the three most common trisonomies and problems on the sex chromosomes as Angnome describes. In this case you would need to be aware that the screening might not pick up all the possible chromosome problems.

With PGS, there are also questions around whether you could be discarding embryos which could have been entirely normal babies due to issues around mosaicism. You can do your own research about this as it’s easily available information.

Whilst in theory one hopes to avoid unsuccessful rounds and miscarriages by using PGS, the actual scientific research that has been done so far suggests that it is less likely to lead to a live birth for older women (those who are most likely to use PGS). This is why the HFEA does not recommend it as an add-on. However the methods are improving all the time so this research may be out of date.

Angnome is also correct to point out that PGS is different to the various types of PGD which look to diagnose specific conditions.

[Hidden in reply to Lizzielizzielizzie]

No problem, I actually think is just nomenclature that we are using differently. Honestly I don't know how each clinic applies PGS and this might differ technically as It progresses and my knowledge of IVF is only as a interested patient, but I had to study lots of genetics during my undergrad (many years ago 😅).

Aneuploidies by definition are changes in the normal number of chromosomes (en.wikipedia.org/wiki/Aneup.... It doesn't include deletions, duplications or translocations, as the ones you describe. What I don't know is exactly the sensitivity of different PGS techniques (that I think is a combination of microarrays, Next generation sequencing and probably others). I know It can pick big deletions and duplications, but also that It is limited in detecting moisaicism and translocations, for example, because the amount of DNA obtained is tiny and because some of these changes don't change the overall chromosomal contribution.

I totally agree that there is a moral question here and that is absolutely personal, same as whether to chose screening for aneuploidies during pregnancy or whether to continue with a pregnancy in which the baby carries a severe genetic condition. Each clinic should be able to respond to the patient requirements, and each patient to chose.

[Hidden]

By the way: we did It with only 3 blastos frozen and I was 35. And we were so lucky the three were normal!!!!

[Lizzielizzielizzie]

I would just have regular ivf unless you are using pgs together with pgd to screen out a genetic/chromosome condition. Look at the hfea website for unbiased advice on add-ons like this x

[Dogpark]

Yes the HFEA doesn’’t recommend it yet it is so popular!

[Lizzielizzielizzie in reply to Dogpark]

That’s because clinics make lots of money from it and they sell hope. (Cynical, moi?!)

[Dogpark in reply to Lizzielizzielizzie]

Do they really? Doesn't it minimise the number of transfers though?

[Lizzielizzielizzie in reply to Lizzielizzielizzie]

I don’t know for sure but that would be my guess. They make less money on transfers I would think because transfers are cheaper.

[Dogpark in reply to Lizzielizzielizzie]

In my clinic, a transfer is more expensive than PGS...

[Lizzielizzielizzie in reply to Dogpark]

Even compared to a fresh transfer?

There was a panorama programme made around 2016 which looked at clinics making profits on add-ons without a huge amount of scientific research to back it. You may still be able to find it online- it’s an interesting watch.

As regards selling hope, I guess people might buy a round with PGS as it gives them hope where they might not buy another round at all without the “carrot” of testing.

At the end of the day, like all these things, you’ll always find stories of people it worked for and people it didn’t; only you can decide what you think based on the scientific evidence available and your personal circumstances coupled with the trust you have in your own clinic. Good luck with whatever you decide to do.