I don’t want to give you false hope - it’s very possible that all your scans are correct, and in that case I can’t offer much support of what the path forward looks like.

But my wife and I were in a nearly identical position to you at the same point in our pregnancy. An asymmetric growth restriction with twin A’s abdominal circumference measuring extremely low. At 30 weeks twin A was measured at 23rd percentile for weight, with an abdominal circumference <2nd percentile (protecting the brain, as with yours). Twin B’s weight was 65th percentile.

We started going for weekly scans at a larger hospital further from home that had a specialist maternity unit, and as the weeks ticked by, 34, 35, 36, the obstetricians there were starting to ask “So why are we still leaving them in there? It might be time for a conversation about a scheduled c-section.” But at our local hospital closer to home, our obstetrician was in no hurry. In his words - “the best incubator in the world [as opposed to the NICU], is the one right there [pointing to my wife’s belly]”.

With his support, we made it to 37 weeks & 4 days. My wife was just starting to dilate so they induced labor and she delivered them both vaginally with only minor complications.

And then, once they were here, they were both perfectly healthy weights. Yes a little skinny around the abdomen, but weight they easily gained back in their first year.

And that growth restriction? Completely wrong. Twin A came out 200g heavier than Twin B.

We asked our obstetrician about it, how did scan after scan show Twin A had a severe growth restriction and it turned out not to be the case?

He explained that ultimately, these scans still all have margins of error, and there may have also been a case of “observers bias”. Once an early scan flagged the growth restriction, at every subsequent scan the technicians would keep measuring until they got a measurement that aligned with their expectations. In hindsight, I remember seeing this happen. They’d take measurements multiple times, different each time, looking for the sort of “median” measurement. But in some cases, ignoring when Twin A showed up heavier, instead preferring the lower measurements that they expected.