During the period of sitting on the moon, the hard lumps appear under the armpit may be paratactic, part of the female congenital with paratactic, after delivery the body by the influence of lactogen will appear milk secretion, including paratactic will appear mammary gland development and lactation increase, paratactic growth, lactation after swelling, will appear under the armpit with hard lumps phenomenon. If there are hard lumps under the armpits, and there are symptoms such as breast swelling and pain, it may be due to the excessive secretion of milk from the breasts and the breast ducts are not smooth, causing breast swelling and pain, which will cause the lymph nodes under the armpits to swell, and there are hard lumps in the armpits. It is recommended to go to the thoracic surgery department of the hospital, cooperate with the doctor to do breast and axillary lymphatic surgery and ultrasound examination, to confirm the diagnosis of paratesticular breast or because of breast swelling and pain inflammation, resulting in axillary lymph node swelling symptoms, after diagnosis, cooperate with the doctor to deal with the symptomatic treatment.