Pressing pain in the breasts before menstruation is considered to be a physiological phenomenon, as the hormone levels in the body change considerably before menstruation, and the levels of estrogen and progesterone in the body are relatively high. Estrogen can stimulate the development of the ducts and glands of the mammary gland, progesterone can stimulate the development of the breast follicles, the two hormones at the same time, the breast gland hyperplasia is more obvious, congestion is also obvious, the volume of the breasts will increase, then press the breasts will produce a painful feeling. But this is a physiological phenomenon, with the onset of menstruation, estrogen and progesterone levels will drop sharply, the feeling of breast swelling and pain will disappear naturally.