Having stared at my wife's vag as she gave birth, you don't want to see that. It's amazing watching your child be born, but there is.... it's not a vagina as you know it. If I wasn't able to compartmentalize and I saw that image in my head every time I had sex with my wife, I'd probably never have sex again.
If someone offered to show me a video of my birth.... I'd probably pass. The creature emerging from that portal to hell has no relation to what any is us became. Also, "I landed on a little poo," isn't something any of us wants to know.
Somewhere out there are fetishists claiming the exception to the rule but.... I'd think twice.