Sometimes anatomy has something to do with it, but not often. I see women having to wear arm guards more than men by the way their arm sits when they hold the bow at full draw.

Also, if you're hunting and wearing several or thick clothes, it's not unusual for the string to hit your forearm, hence the tip about the arm guard is a good one.

(right-handed) If at full draw your wrist is sitting straight up and down, you have your hand too much into the grip. If this is the case, you'll have to rotate your hand to the right or counter-clockwise about 35°-40°. Hard to say in degrees.

I have attached a pic illustration to view.

iSnipe