The term “great aunt” generally refers to a woman’s menstrual period. Low menstrual flow can be caused by many factors, such as excessive dieting, depression and other physiological factors, as well as polycystic ovary syndrome, early onset ovarian insufficiency and other diseases. 1. Physiological factors: Usually, patients with poor dietary habits, excessive dieting for weight loss or long-term anxiety, depression and other adverse emotions will often affect the endocrine function, which can lead to low menstrual flow. 2. Polycystic Ovary Syndrome: The cause of this disease is still unclear, mostly due to the combined effect of heredity and environment. Generally, patients in puberty and childbearing period often have scanty menstruation, low menstrual flow or amenorrhea, which can be manifested as low menstrual flow. 3. Early-onset ovarian insufficiency: the cause of this disease is more complicated, most patients do not have a clear cause, and most of them are considered to be related to autoimmune diseases, medical injury, chromosomal abnormalities and other factors. Usually, patients will have scanty or frequent menstruation in the early stage, or even amenorrhea, which can also lead to scanty menstruation. There may also be other reasons for scanty menstruation, so it is recommended that the patient should consult a doctor in time, complete the relevant examinations, identify the cause of the disease under the guidance of a professional doctor, and target the treatment.