humor me pls: di-di twins and IVF

LnR70707

So discussing the article posted below got me thinking, and I've been meaning to ask my RE this but always forget.   As a non-MoM, my knowledge isn't all that great, but di-di twins usually split between 1-3 days after fertilization (right?).  So for IVF, would it be feasible that they could fully split before a 5 or 6 day transfer....would they be able to see that and transfer them separately?  No real point to this question, just curious so hopefully it isn't an entirely ridiculous one.

ougrad1

Glad you posted this.  I want to know the answer, too!

pea-kay

I know there's someone out there with di/di IVF identical twins, but frankly, I'm not sure how that happens. Maybe they split in the petri dish? But I assume they count the embryos? I don't know all of the exact details of IVF, but generally speaking, IVF does not produce di/di identicals. The split would happen before they're transferred, and I'd think they keep a pretty close eye on what happens to them in the lab.

Rynleigh

As far as I know (never had any infertility treatments), they manually select the embryos to transfer, one at a time. If the embryo is selected at day 5 and implanted that day, there is no way for it to split into a true di/di identical pregnancy. They also do not split while frozen. If you have IVF and the twins are di/di, it is almost always going to be because two separate fraternal embryos took. 

Di/Di twins in a natural conception have a very low chance of being identical (varied studies show anywhere from 16%-30% of identical twins being Di/Di - and since identicals only make up about a third of all twins, that drops even further - making "Identical Di/Di" twins equate to only about  5%-10% of all Di/Di twins in natural conception. For IVF, it's simply too improbable. 

Temp123197812503460

I had the same question after reading that, how wacky would it be to have ID "twins" of different ages?I wonder if you can have them split in the dish...

April+

Rynleigh:

As far as I know (never had any infertility treatments), they manually select the embryos to transfer, one at a time. If the embryo is selected at day 5 and implanted that day, there is no way for it to split into a true di/di identical pregnancy. They also do not split while frozen. If you have IVF and the twins are di/di, it is almost always going to be because two separate fraternal embryos took. 

This isn't true, IVF does not always results in fraternal twins, it is still possible for identical twins. There are many cases where only 2 embryos were transfered and 1 of those embryos split = Triplets. 

Rynleigh

April+:

This isn't true, IVF does not always results in fraternal twins, it is still possible for identical twins. There are many cases where only 2 embryos were transfered and 1 of those embryos split = Triplets. 

 

Identical twins, yes - absolutely - the kind that split *after* IVF, i.e. after day 3, i.e. NOT Di/Di.  

E&RMommy

Apparently di/di monozygotic twins have happened after day 5 transfer single embryo transfer.

Yes this goes against everything we know or thought we knew about zygostiy and chorionicity.

 

kiwi443

E&RMommy:

Apparently di/di monozygotic twins have happened after day 5 transfer single embryo transfer.

Yes this goes against everything we know or thought we knew about zygostiy and chorionicity.

 

Yes. I think festivus is the poster here whose di/di IVF twins are identical.

Temp6313048411121614

I know of 4 separate cases off the top of my head that have ID's from IVF.  1 of them did a SET, so obviously it split after the transfer.

pea-kay

Mo/di is not uncommon after IVF. Di/di is very rare in that situation.

regenab

I have no knowledge of this, but I did do IVF. I had a day 3 transfer which is the most common type of transfer at MY clinic, so I would imagine you could have some Di-Di Identical IVF twins with a 3 day transfer.

LnR70707

thanks ladies!