Around one in five women of reproductive age have small cysts on their ovaries. Polycystic ovaries is the term which describes the appearance of the ovaries when they are seen on an ultrasound scan. A small fraction of women with polycystic ovaries will be troubled by certain symptoms (irregular periods, obesity, hirsuitism, acne) and in that case their condition is given the term polycystic ovary syndrome (PCOS). So not all women with polycystic ovaries have polycystic ovary syndrome, but all women with PCOS do have polycystic ovaries.