Breast tenderness is a sharp or dull pain that is usually accompanied with swelling.
What is the reason of this?
Most women complain of breast tenderness and pain in the first few weeks before milk production begins. When the egg is fertilized and placed in the lining of the uterus, progesterone and estrogen are released into the body. These hormones increase blood flow in the body and support fat storage in preparation for pregnancy and childbirth. These changes alone can cause irritation and pain.
Tips
Bras and breast pads. Wearing sports bras to minimize the movement of your breasts is said to help with pain and tenderness. Some people find that the warm water and steam from a good shower helps relieve pain; however, with nipple massage to relieve pain, you may cause your uterus to receive warning signs for birth, avoid it.
It's important to remember that some breast cancers can be hormonally active, so as always you should watch out for new lumps, sore areas, and skin changes in the area and discuss them with your healthcare provider.

