The basic approach is an assessment of the sex hormones, and other diagnostic tools include but are not restricted to pelvic examination, abdominal or transvaginal ultrasound, progestin challenge, cerebral magnetic resonance imaging (MRI) scan, detailed personal history collection with a focus on diet, eating disorders, exercise, weight, development, menstruation and mental distress, bone mineral density test, detection of thyroid hormones, prolactin (PRL) determination, and GnRH stimulation test. This evidence concerns the gene PRL and eating disorder.