... did you have a very big baby?

Someone I know is about to have a baby and is "not allowed" to go past 40 weeks. There is a bit of big baby = bad birth fear-mongering, and I just wonder how much basis there is in it.

I went to 41 weeks 5 days. Baby was 4.07kg.

^ I know that my stats are probably playing on her mind a little bit. But at the same time, I had a big baby and an awesome birth, so I hope that's a consideration too.