I have two daughters and both times my waters did not break until a very advanced stage of labour.
The first time, it was about 2hrs before the birth and I remember a beautiful feeling of release and relief.
The second time, my waters did not break until the baby's head was emerging. The baby slid out very quickly and unexpectedly, which was quite comical because there was so much mess all at once! My membranes must have been tough as leather...