Teenage girls who have never had children may also grow breast tumors such as breast fibroadenoma and breast cancer, because there is no direct relationship between the occurrence of breast tumors and having children. 1. Breast fibroadenoma: It is a common breast tumor in young women, with the highest incidence at the age of 20-25 years old, followed by 15-20 years old and 25-30 years old. The etiology may be related to the quantitative or qualitative abnormality of estrogen receptor contained in fibroblasts. Clinical treatment is mainly based on surgical excision. 2. Breast cancer: the incidence of this disease gradually increases after the age of 20, and is higher at the age of 45~50. Its etiology is not yet clear and may be related to endocrine hormone imbalance. In addition, early age of menarche, late age of menopause, infertility and late age of first full-term delivery are all related to the incidence of breast cancer. Breast cancer often requires surgical treatment or adjuvant radiotherapy in clinical practice. Therefore, it is not true that young girls who have not given birth to children will not get breast cancer. They should have regular physical checkups and go to the hospital in time if they have nodules or other discomforts in their breasts, so as to clarify the cause of the disease through examination and actively cooperate with the treatment.