I was born a so called 'whopper' at just over 9lb. My mum is (and was) tiny and I was a one hour (literally from start to finish) natural vaginal birth.

My OB referred to our DD as Hugh-e (read 'huge'!) from 35ish weeks due to our scans. Admittedly he changed his mind around 38 weeks which was good for him given she was born a tiny 6lb 8oz!!!

As the others have said, scans are not a reliable source for predicting your baby's size. And not being able to birth a so called 'large' baby is often a crazy statement.

Good luck!