Anyone else with a baby with small abdomen on ultrasound?

Abbie

We have been told baby girl has a small abdomen. 36 weeks at 35.5 we had a specialist appointment her belly is still small. The specialist doesn't want her to stay until 39 weeks. We will get with regular dr tomorrow for a further plan. But anyone else had an experience with this?

Both me and hubby are smaller people. Long legs just both have a small frame. But they say it's not that. So any advice out there?