At 23 weeks - and the OB says they could be identical - what?!

AlexPuppy

At my appt this afternoon my OB mentions that there is a slim chance they could be identical twins.  I politely reminded her that we did IVF, inserted two embryos, saw two sacks, and there are two placentas.  She said yes, but depending on when the egg would have split, they could be identical. 

Does this sound right to you ladies?  Is it really possible?  Or should I be double checking my OB's qualifications? 

Chari44

Yes, it is possible. Do a little research on it. 

pea-kay

it is true, but i would think in your case, unlikely. identical twins can have separate placentas/sacs/everything.

however, maybe in the case of IVF, ID twins have to share a placenta, because of the timing of everything? not sure about that, exactly. the egg would have to split v early for them to have separate placentas, maybe earlier than possible with IVF? hmm.

kimarino13

I did IVF, too, and in order for them to be identical but have separate placentas, I *think* they would have had to split really early, like when they were still in the dish.  Mine share a placenta, and split soon after my 5-day transfer.

jalaiaa

unlikely, but possible

kelliwill

Chari44:

Yes, it is possible. Do a little research on it.?

This. ?I think that it totally depends on when the egg split. ?I'd do some research on it. ?

jacobandcrystal

Even though you did IVF, you could still end up with identicals.  The question shouldn't have been "when the egg split", but rather "IF an egg" split"! : )

pea-kay

jacobandcrystal:

Even though you did IVF, you could still end up with identicals.  The question shouldn't have been "when the egg split", but rather "IF an egg" split"! : )

not really true. if it has already been established that she had two gestational sacs, then it is important when the egg split.  the egg would have had to split v early for two gestationals sacs to have formed, and with IVF, i'm not sure if that kind of timing is possible.

jacobandcrystal

pea-kay:

jacobandcrystal:

Even though you did IVF, you could still end up with identicals.  The question shouldn't have been "when the egg split", but rather "IF an egg" split"! : )

not really true. if it has already been established that she had two gestational sacs, then it is important when the egg split.  the egg would have had to split v early for two gestationals sacs to have formed, and with IVF, i'm not sure if that kind of timing is possible.

True, I understand that identicals' # of placentas/sacs depends on timing... my point is that it's possible that an egg didn't split at all.  Maybe I'm missing part of the story?  I thought she was assuming that her twins were the result of the 2 separate embryos implanted.  Which could still be the case.  IF an egg did actually split though, then she could still have identicals with 2 placentas and 2 sacs.

pea-kay

jacobandcrystal:

pea-kay:

jacobandcrystal:

Even though you did IVF, you could still end up with identicals.  The question shouldn't have been "when the egg split", but rather "IF an egg" split"! : )

not really true. if it has already been established that she had two gestational sacs, then it is important when the egg split.  the egg would have had to split v early for two gestationals sacs to have formed, and with IVF, i'm not sure if that kind of timing is possible.

True, I understand that identicals' # of placentas/sacs depends on timing... my point is that it's possible that an egg didn't split at all.  Maybe I'm missing part of the story?  I thought she was assuming that her twins were the result of the 2 separate embryos implanted.  Which could still be the case.  IF an egg did actually split though, then she could still have identicals with 2 placentas and 2 sacs.

well, yeah. i just don't think with IVF, the timing can work so that you can have di/di IDs. (but i really don't know, i'm just basing that off something i read somewhere. )

but in the end, chances are, her twins are fraternal. which is good. easier that way.

jacobandcrystal

pea-kay:

jacobandcrystal:

pea-kay:

jacobandcrystal:

Even though you did IVF, you could still end up with identicals.  The question shouldn't have been "when the egg split", but rather "IF an egg" split"! : )

not really true. if it has already been established that she had two gestational sacs, then it is important when the egg split.  the egg would have had to split v early for two gestationals sacs to have formed, and with IVF, i'm not sure if that kind of timing is possible.

True, I understand that identicals' # of placentas/sacs depends on timing... my point is that it's possible that an egg didn't split at all.  Maybe I'm missing part of the story?  I thought she was assuming that her twins were the result of the 2 separate embryos implanted.  Which could still be the case.  IF an egg did actually split though, then she could still have identicals with 2 placentas and 2 sacs.

well, yeah. i just don't think with IVF, the timing can work so that you can have di/di IDs. (but i really don't know, i'm just basing that off something i read somewhere. )

but in the end, chances are, her twins are fraternal. which is good. easier that way.

I see what you're saying.  It is a very interesting question!

Original poster:  When we heard that ours were identical, I did a bunch of research on how that might happen. I was reading that doctors can often tell which blastocysts have two inner cell masses, which raises the possibility of splitting into identicals.  Maybe you could ask your fertility doc whether they noticed that?  Or what their take is on the possibility of yours being identical?

*Sorry if not using proper terms... I'm not really familiar with the IVF process. ; )

kimarino13

I think it's unlikely because she did IVF and the twins have separate placentas.  For that to happen, the egg would have had to split very early on -- probably when it was still in the dish.  I think that's why it's unlikely in her case.

I did IVF and mine are identicals, but they share a placenta, meaning the split occured later than an ID twin pregnancy with separate sacs.  If they had split even later than mine, then they end up sharing an amniotic sac.  The later they split, the more they share.

jacobandcrystal

Sorry to post again... I'm a big research nut and this is an interesting question.

Wikipedia states that di/di identicals split in the first 1-3 days.  When embryos are implanted, how long is it after sperm met egg?  Is it possibly within those first 3 days?

kimarino13

Embryos are typically transfered back into the womb 3 days after fertilization or 5 days after fertilization.  This is why if they are di/di identicals and OP had a 5-day transfer, they would have seen the split in the dish.

AlexPuppy

Hi ladies!

Sorry for the delay... I didn't realize there would be so many questions around my post.  So, let's see if I can sum up answers to the questions/observations I saw.

- We did a 5 day transfer, one was appearing to already 'hatch' in the picture they gave us of the two we chose to put in.  The pic was taken just minutes before they put them in.  But again, it was 5 days after the sperm met the egg.  And I'm not sure if hatching means anything with regards to splitting.

- I did some googling, and it appears to be a 1-5% chance that they are identical, but nothing that I saw fits our exact story.  Which makes me think that our OB wasn't thinking through all the timing of it.  We saw an RE for our fertility stuff and transferred to this OB at about 10 weeks (IIRC).  So, I'm guessing that they are fraternal.

So, I suppose we'll just have to wait and see.  I certainly wont put money on this.  But that sure would be a trip to have thought this whole time that they were fraternal and they ended up identical.  Nuts!  We'll know sometime in Feb. 

mmbench

Long story short - there's a possibility or a case of almost everything when it comes to ID's.  The ONLY way to know for sure is a DNA test (or if they're b/g). 

MrsARC1105

MrsLee04:

jalaiaa:

unlikely, but possible

"Unlikely" is not really true.  IVF tends to increase the rate of identicals, and I hear/read about it all the time. 

This. The procedure behind IVF makes it "easier" for the eggs to split. 

To original poster, just get a DNA after they are born if you really want to know