Breast pain is very common, why? Because there are many nerves running through the breast glands, and when the structure of the gland changes, or when the gland is hormonally stimulated and becomes engorged and edematous, these nerves will be stretched and compressed and cause pain. During breastfeeding, the gland is sometimes swollen and retracted, so it is very painful to have stabbing pains or some painful symptoms, often related to the release of oxytocin, which causes the contraction of the lobules, perifollicular and periductal muscle cells to promote the discharge of milk. This causes pain.