According to G. Kloosterman, Dutch professor of obstetrics,
Spontaneous labor in a normal woman is an event marked by a number of processes so complicated and so perfectly attuned to each other that any interference will only detract from the optimal character. The only thing required from the bystanders is that they show respect for this awe-inspiring process by complying with the first rule of medicine–nil nocere [do no harm].
I found this quote in Gentle Birth, Gentle Mothering and thought it was worth sharing.
A House Rises 