how far along do i have to be?

Hi!! I am 15 weeks and new here! I was just wondering how far along do I have to be to find out whether they are fraternal or identical?

 

They should be able to tell you whether your babies share a placenta or have their own when you go for an ultrasound. If they share a placenta, they are identical. If they each have their own the only way you'll be able to tell for sure in utero is if they are of opposite genders (which would obviously mean they are fraternal)

 

I agree with the Previous Poster. My two each have their own sacs and their own placentas, but are both girls, so I still have about a 20-30% chance that they are identical. The only way I will know now is when they come out. If they look alike and have the same blood type, then I will have them DNA tested. If they don't look alike or have different blood type, hair color or anything like that, then I can assume they are fraternal. At least I still have one surprise left!! Good luck!!

 

Thank you!! I have had three u/s already but my doctor is sending me to a specialist next week to find out whether or not my babies share a placenta. I think they are probably fraternal because that's what runs in my family but I'm not sure.

 

Even if it looks like just one placenta though you can never be 100% sure unless it's a boy and a girl as two placentas can fuse into one early on in the pregnancy. In that case they won't REALLY be able to tell if it's one placenta until they inspect it at birth. Usually though they can make a decent guess by whether or not there are one or two placentas and also the thickness of the membrane between the babies.

 

That's what I thought too but was wrong! Identical - dna tested at 15 months old.

 

Actually, a few years ago they discovered that fraternal twins can share a placenta (not just 2 fused looking like 1 either). http://www.msnbc.msn.com/id/3077080

Identical twins can have 2 separate placentas
http://www.msnbc.msn.com/id/3077080

Identical twins can have 2 gestational sacs
http://www.gynob.com/fratidentwins.htm

So the only way to tell would be if they were boy/girl, were both in one sac, or you had DNA testing done. That's my understanding from all the reading I've done.

 

But even a boy and girl can--uner very rare circumstances--be identical (ie, from one egg).