The breast tenderness before menstruation can occur, but just after pregnancy can also occur, the symptoms between the two breast tenderness, basically similar, but there are also the following differences. The breast swelling and pain before menstruation is usually regular and occurs during the second half of menstruation. The breast swelling and pain is caused by the increase of progesterone, which stimulates the breast cells and causes breast enlargement. Breast pain caused by early pregnancy is also due to the increase of progesterone and estrogen, which causes the enlargement of breast ducts and cells, but the pain will last longer and will continue to be experienced until the onset of menstruation. In addition, small nodules may appear near the nipples after pregnancy, which is also a unique breast change after pregnancy.