Massive hair loss may be related to androgen abnormality, baldness, endocrine abnormality and so on. 1. Androgen abnormality: Due to excessive secretion of androgen in the body or excessive androgen in the scalp follicles, the hair follicles gradually shrink and lose their activity. Usually occurs in puberty, men mainly manifested as frontal and head hair loss. In women, hair on the top of the head gradually becomes finer and smaller, but the position of the forehead hairline remains unchanged. 2. Patchy baldness: mostly caused by excessive emotional ups and downs, endocrine abnormalities, heredity and autoimmunity. Hair follicles are damaged and a round or oval patchy area of hair loss suddenly appears. The scalp may be itchy or painful before the hair falls out. 3. Endocrine abnormality: Polycystic ovary syndrome can cause long-term hormone secretion disorders, or suffer from some thyroid diseases, resulting in over or under secretion of thyroxine, which can disrupt the cycle of hair growth and lead to hair loss. When a large amount of hair loss occurs, it is recommended to consult a doctor in time, follow the doctor’s instructions to choose the appropriate examination method, clarify the cause with the help of the doctor, and carry out targeted treatment or therapy.