Well, you could have a variable written to each time it loops,,,
I have included a FLA that accomplishes this, I hope it helps....
Note: In the fla, there is a symbol that is animated (animation within the MC). In frame one of the mc (its a ball), I set two variables. One for how many times it should loop, and the other just declaring for a counter. On frame 20, there is an conditional that either stops the movie if the counter var equals the howManyTimes it should loop variable (one of the two vars set in frame one of the ball symbol), or it increments the counter var and goes to frame two (because one of the vars declared in frame 1 gets incremented in frame 20, we cannot loop back to frame 1 (it would reset the counter to zero and we'd be in an infinite loop)).