There are many reasons for scanty, irregular periods, such as high prolactin and abnormal thyroid function, which are not necessarily caused by polycystic ovary syndrome. In addition to polycystic ovary syndrome, high prolactin or abnormal thyroid function may cause scanty and irregular menstruation. Polycystic ovary syndrome is mainly characterized by hirsuteness, obesity, facial acne, scanty menstruation, ovulation disorders and infertility. If you have scanty menstruation or irregular menstruation, it is recommended that you go to the gynecology department of the hospital for a blood test for sex hormone six and thyroid function and ultrasound to make a clear diagnosis, find out the specific cause, and treat it under the guidance of the doctor.