I guess my main reason for asking whether the cord needs to be cut after the injection is that I would hate for women on this forum to think that they can let the cord pulsate after the shot if is not true. I don't have a medical background, so I don't know anything about it, only what I have read, and that was that once you have the shot the cord needs to be clamped. I could imagine it would be pretty awful for someone here to go into labour thinking they can have the shot only to be then told afterwards the cord needs to be cut when it wasn't what they wanted.
My homebirth midwife actually doesn't do the synto shot as routine so that to me (and I trust her completely) says it is not necessary for everyone because I am sure if it was dangerous then she would do it.