I was more terrified of pooing and piles than I was of actually giving birth!
I didn't poo with DS1 but did end up with huge piles, not sure what happened tbh, bit of a balls up with anti-nausea medication.
With DS2 it was massively humiliating as DP tried to make light of it by asking if anyone wanted to play "Boats" 
I took this in very bad humour and screamed
"Will you shut it! I'm having a rectal prolapse here!!!"
Still feel a bit
now!