Have you heard this?

My LO was sunny side up/brow presentation and I pushed her out after one hour of pushing (I tore in a star shape and had 30+ stitches).

My friend just gave birth and ended up getting a c-section because her baby was posterior. She told me her doctor said that most women can't push out sunny side up babies unless they have given birth before. That was news to me??

Anyone know anything on the subject?