Here is a good article on Silent Birth with an actual example of one: Scientology's Silent Birth: One Mother's Story.
One point I wanted to make: there is a comment from a doctor that implies that quiet during birth makes no difference. What she is missing is that the whole point of silent birth is to avoid words spoken during a traumatic birth. Sure if the birth contains no pain and unconsciousness for the mother and baby then you could have a brass band playing if you really wanted to. But how can you guarantee that there won't be any pain or unconsciousness?
It is easy to demonstrate the effect upon a person of words spoken during moments of pain and unconsciousness. Those words act like a post-hypnotic suggestion. E.g., If the mother says "the smell of antiseptic makes me feel sick" during a traumatic birth, then it is likely in later life (once meaning can be assigned to the words) that the grown child will feel sick when he or she smells antiseptic.
For more details on this read the book Dianetics: The Modern Science of Mental Health