Layers of funny:

If I were a OBGYN, I would assume mothers in labor like really funny jokes, so I would definitely get a terrified look on my face whenever I delivered a baby, and hire an actress to pretend to be a nurse and she would gasp in horror and say "Santa Maria!" and make the sign of the cross and step away in shock when the babies head came out, and then I would say "Nurse, get a hold of yourself", but I'm pretty sure all that would have happened with Paltrow anyway. Which is cool because actresses with their own nurse outfit probably aren't cheap.