Question about mono/di twins

Shelby425

Hi ladies,

I went for my 12 week u/s today. The doctor said things look great. Baby A is in its own sac and measuring at 12 weeks, b and c are mono/di, b is measuring at 12w 1 d, c is 11w 4d. The doctor was not concerned about the size difference between b and c but of course it has me wondering. Has anyone else had this experience with their mono/di twins?

jcath

Sure - my girls always measured a couple days apart up to a week, interestingly enough when they were born their heights and weights were identical.  I think they worry if there is more than a week difference but even then everything can be fine.

Mrs. Alice

Yes I always had a smaller baby.  At 12 weeks they are really only doing crown to rump measurements.  At 14 weeks mine were about a week apart.  We think because A was all scrunched up and the Dr. couldn't get a good measurement.  By the next month they were just an ounce apart.  It wasn't until 22 weeks we started seeing a larger size discrepency.  They were about 20% different at birth. Measuring 4 days apart is well within normal.  If your Dr. isn't concerned, try not to worry! 

Mrs_MBed

Our boys varied between measuring together and measuring a few days to a week apart.  I wouldn't worry if the doctor isn't worrying. 

ninjabridemom

Yeah our boys are always a few days or ounces apart -- they alternate who's in the lead   I think they start worrying when the difference is about a pound.

 

If you go to the TTTS Foundation website it will give you more specific numbers, but it sounds like your OB knows what to look for.

angelfire02

Our babies were a few days apart up until 18 weeks, at that scan they were exactly the same but now we are at 24 weeks and they are back to being a few days apart.  We are monitored every other week by the MFM doctor for TTTS and they haven't had any concerns.  As long as your doctor is on top of any issues that may come up the size difference shouldn't worry you, they will tell you if they are concerned.  Congrats on making it to 12 weeks!!!!   I felt so much better once I was into the 2nd trimester!

Switzerland87

It's not uncommon for mo/di twins to have one bigger than the other. My Baby A is a little bigger than Baby B in weight, and measures a couple of days ahead as well. My OB says it's only cause for concern if the size difference becomes 20% or greater. 

amanda31H

I agree with all the other ladies....but I was wondering if you knew what you care plan was going forward?  How frequent are your u/s to monitor for TTS and your  triplets in general?

kiwi443

My girls measured within ounces of each other up until about week 28. Then, one started measuring small and was classified as IUGR. There were never signs of TTTS. They were 1 1/2 pounds apart at birth, but both healthy.

Congrats and best wishes for your pregnancy.

flutepharm87

In the beginning, the boys were pretty spot on as far as size. But as the pregnancy progressed, there was definite weight discordance. Right now, Jack is a little less than a pound heavier than Ian. I wouldn't be too concerned about it for now as long as your doc is OK with it. With multiples, you'll be monitored much more closely, so your OB will be making sure the weight discordance doesn't get to a worrisome point.

13pickle

at 12 weeks they can be so wiggly it is hard to get super accurate measurements, so a few days seems pretty normal. just keep cookin' mama!