It happens and is one more reason the bull should not run with the cows except during a fixed breeding season.
Several years ago we had a gomer that was playing with a calf as it was born. The calf head would start to protrude and the gomer would head push with it and push it back in. As soon as the head started out agina he pushed it back again. It happened half a dozen times until the cow got up, knocked the living crap out of gomer, laid down and squirted the calf out. Gomer sniffed the new calf and when it wouldn't "play" anymore, walked away and ignored the calf from now on. Hilarious to watch once, but rather worrisome to see happen several times.