Breast tenderness during pregnancy lasts for about 3 months. The secretion of estrogen and progesterone in the body increases significantly in the first trimester, which can easily stimulate breast tenderness. If the swelling and pain is serious, you need to go to the hospital for ultrasound to rule out breast enlargement, which can cause breast cancer, you need to review regularly and take breast dissipating herbs to regulate if necessary. Hot compresses and massage can relieve the pain.