Basically what happens is that by around 8 months of pregnancy, there's not much space left in the uterus and so baby tries to expand its cramped areas by settling in the head-down position. So that makes the baby take a turn, as a result, he becomes poised to come out by exiting the buttocks or feet first instead of the head.
Well, one such mother who was facing breech baby condition underwent external cephalic version and the doctors reversed the breech baby position by massaging in just 2 minutes. Wonderful, isn't it? Have a look at the whole scenario.