You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is A 21-year-old unmarried woman has premenstrual fullness of breast and pain, the likely diagnosis is: and explain in detail?
It is usually seen in women of 4th and 5th decade of life (also not rare in young females) with complain of an intermittent mammary discomfort or an area of lumpiness or nodularity in the breast.
The changes are generally bilateral. Pain is cyclical with a premenstrual exacerbation.
Most likely the girl in question is suffering from fibroadenosis though her age is not consistent with the fibroadenosis.