I have twitching in my rib area, just below my breast. it is becoming more frequent and uncomfortable. what could be the cause?

Common and benign.: Twitching is what happens in a muscle, and it can be a result of fatigue of the muscle or the nerve leading to that muscle. There are muscles throughout the ribs below your breast, so that is what you feel. Muscle twitches are common and usually nothing to worry about, especially if they are in one muscle and come and go. Are you wearing something (bra) that is too tight on that side?