Unexpected pain can occur under the left breast for reasons that range . sudden, severe pain under the left breast and in the upper center part.
Under and around the left breastbone are the heart, spleen, stomach, sharp, stabbing pain, often on the left side of the chest; sudden onset.
Are you experiencing pain under your left rib? Costochondritis refers to inflammation of the cartilage that attaches your ribs to your breastbone. It causes a sharp, stabbing pain that's usually felt on the left side of your rib.
If you have acute pericarditis, the most common symptom is sharp, stabbing chest pain behind the breastbone or in the left side of your chest.
Gallbladder pain is usually felt just below the breastbone and may of pericarditis is a sharp, stabbing pain in the center or left side of the chest.