Twins - size difference - TTTS, GD or nothing to worry about?

[gemcxx]

Hi just looking for any similar stories!

I’m 31 weeks with identical twins, up until my 28 week scan there was never any more than 10g between them and then at my 28 week scan there was 100g between them - one was 2lbs 10oz, just above 50th centile, and one was 2lbs 7oz, just below 50th centile. A size difference of 9%

At my 30 week scan there was 190g between them, one had dropped to the 40th centile at 3lbs 3oz, and the other had gone up to the 75th centile at 3lbs 10oz. A size difference of 15%.

They said they start to worry about twin-twin transfusion syndrome when the size difference gets to 20% but they weren’t concerned about it at my last scan.

I’m worried for my scan next week in case that difference has increased to the 20%. I know TTTS can come on quickly so I’m panicking about how big the size difference might be next time. But I also have gestational diabetes and I’m wondering whether this could explain the size increase in the larger twin.

I’m just wondering for those twin mums with GD, have you found both babies are bigger than average or just one, or maybe no increase in size at all? I’m not sure if the diabetes would normally affect just one baby or both? I would assume both but not sure.

For twin mums without GD do you have a similar size difference between your babies as me or are they roughly the same size as each other? A 7oz difference doesn’t sound like much but they’ve got me panicking the number is creeping up closer to that 20% difference figure

My twins were 1lb2oz different at birth at 36w, despite scans saying they were similar... no GD. have you had a Doppler scan to check blood flow through the placenta?

Thanks for your reply, yeah they’ve checked at every scan, they never say a lot about the numbers but I’m assuming all was okay as they never mentioned there was an issue, same with deepest pools so keeping my fingers crossed it’s not the start of TTTS and just a normal size difference

My boys were 7lb and 5lb. ... I remember s huge faf at about 36weeks when they said twin1 seems to have lost about a lb in weight ....just as twin2 seemed to have put on about a lb ... I casually suggested they may have swapped positions...and after more scans loooong waits and sat in front of a consultant they decided to further monitor me....a week later they agreed they probably had swapped positions :)
At 11 small twin is now 30lb and 25cm larger than his "big" brother :)

Ah wow as if you had to go through all that faf and they had just swapped places, that’s good though that’s all it was :) also great to know size difference clearly has no long term meaning 😊

If they are worried, they will be very vigilant... my twins are still about a 1lb different in size and they are almost three!
Hope all stays ok xx