1. Than can be caused by chest pain while breastfeeding?
From that, what is the reason of a discomfort, and depends what you need to do to make the pain is gone. For example, if the pain in the nipples, the cause may be insufficient deep attachment to the breast (including the tongue-tie a baby or his habit of bottle), or an infection, such as thrush (especially if it is a burning sensation after feeding), or a bacterial infection (particularly when cracks). There is also such a rare phenomenon as vasospasm (the nipple changes color after feeding, and there is pain), eczema. If the pain more felt inside of the chest, it could be an excess of milk, milk stagnation and even mastitis.