A headache once menstruation is considered to be related to hormonal changes, insufficient blood supply to the brain, cold and other factors. 1. Hormonal changes: During menstruation, the level of estrogen and progesterone in the body decreases significantly, which in turn affects the patient’s neurological function, so the patient will have a headache. 2. Insufficient blood supply to the brain: for women with heavy menstruation, it may lead to insufficient blood supply to the brain, so headaches, fatigue and other discomforts will occur. 3. Cold: the body’s resistance is lower during menstruation, if the patient does not pay attention to keep warm, headache, runny nose and other manifestations may occur. For patients who have headaches once menstruation, it is recommended that they go to the gynecology department of a regular hospital for consultation and active treatment under the guidance of a doctor after clarifying the cause of the disease.