when I was planning a natural birth and third stage, the midwife at the hospital wanted to write on the birth plan that we would wait 20 minutes and then I would have the injection. She stated that this was long enough for my "care provider" (I'm guessing she meant the obstetrician) to wait. She also said that as my careplan stated that we wanted to wait for the cord to stop pulsating before being cut, this would probably mean that by the time we'd waited for that, the placenta would be born anyway.

This has left me with some questions:
1. What, if any, is the relationship between the cord stopping pulsating and the birth of the placenta?
2. How is a placenta birthed naturally ie do you have someone pulling on it or let it come out on its own etc?
3. What is the obstetrician's role (private hospital) in birthing the placenta. Obviously if you need stitches, they have to wait until the placenta is birthed, but what apart from that?