Twins--one sac smaller than the other

Question

I had an follow-up u/s today (6 weeks 5 days) and it again showed 2 sacs, but this time there was a baby in the second sac!

We saw 2 heartbeats, but the second sac and baby are smaller than the first one. 

My RE says that both heartbeats are perfect, but the second sac and baby are measuring smaller than the first.  He said there is a 50/50 chance of it being viable.

Has anyone had this happen and had success with carrying twins?  It's just so hard to believe that it has a strong heartbeat now, it's just smaller, and that it might not make it!

Quintenswife2003 · Answer

Im 7 weeks pregnant with twins. My 2nd set natural unmedicaded.
The twin A  measured 6 weeks 5 days with a heart beat
TwinB no fetal pole measures 5 days behind and i see a another yolk in tht sac? Could be triplets? 
Can u look at my pictures?

JTDs Mom · Answer

That's exactly what both my mother and DH said--that the smaller twin was going to be a small, petite girl! I guess we'll just have to wait and see--I have another u/s in about 2 weeks, so we'll see what's going on then!

Brown Eyed Gurl · Answer

no they never told me I might lose the one now I did lose a third I actually conceived triplets but lost one but still it's possible to Ovulate 2 times in a month and even 2-3 weeks apart the fact he said both babies had good heartbeats would say alot for me.....but like I said my girl is always behind my boy

Kash12 · Answer

Hi JTD's Mom ... Let me share with u something from my exp... I had an U/S yesterday and my RE tried to measure the babies(twins) . At one time he measured them to 6w6d and the other time at 8w. I was 7w2d yesterday. He said that at this stage they are so small that its difficult to find the CRL(Crown Rump Length) . He had to mark the beginning and end point for the babies and even a mm of diff makes the dates off by a couple of days. Also the position of the baby and the quality of the equipment makes a diff. The angle at which the vaginal U/S wand is kept makes the difference on how much of the baby u see. The week 8 U/S will give u a better idea on the dating.
So try to relax about the dating part based on U/S. They can sometimes be a little off. good luck and keep us posted:)

JTDs Mom · Answer

Well, I asked my RE about their measurements and he just said that the first one was "right on the money" and the other one was "smaller"--he didnt give specific numbers or how many days behind it was.

It's obvious on the u/s pictures I have that the second sac is smaller than the first, but there seems to be plenty of fluid around the baby anyway.  And there was a heartbeat--again, not sure of the bpm, but my RE said that both babies' heartbeats were really good.

BrownEyedGurl--did your RE tell you that you had a 50/50 chance of keeping your smaller twin?  I'm sure that mine says that as a CYA--I mean, if something DID happen and I lost it he wouldnt want to give me some false sense of hope that it was all good.  

My mom says that rather than saying I have a 50% chance of loosing it, I need to be positive and say there is a 50% chance I'll keep it!