The only other time I've seen a hairy woman was when I was the 2nd AD on a short film and the 1st AD was directing a little kid on how to do a stunt. She fell off a stool and onto a mat and her arms fell above her head. Pit hair came peeking out of her polo shirt.
I've seen it twice - once with an Italian friend who didn't care much about pit hair until she started dating when we went to university, and a French exchange student who proudly displayed her pits whilst trying to chat people up... at 14 (or perhaps any age) thats not going to work.
As for the question, I keep mine in shape with clipper regularly. In wrestling the less hair you have the better - hygene logic aside, the last thing you want is to find yourself in a headlock with hair and sweat.