Left Hand Percherons, its really difficult to deliver a live foal prematurely. The saying is that the foal decides the foaling date. If you go in and try to do a C-section on a mare that's not actively foaling then you are just killing the foal. Which is really different from dogs and cats where you can sort of play with due dates and still get a live baby. Induction of labor is the same thing, if the baby is not "ready" then its not going to live. The mare can decide the hour but the baby decides the date.