Amenorrhea is the lack of menstruation, one or more missed menstrual periods. Women who have lost at least three menses in a row and also girls who do not start menstruation at the age of 15 years. The most common cause of menstruation is pregnancy. Other causes of amenorrhea are problems with the reproductive organs or glands that contribute to the regulation of hormone levels. The treatment of the basal condition often eliminates the absence of menstruation. Causes: Following factors may be responsible for this disorder Pregnancy Hormonal problem Any problem of reproductive organ Symptoms: It is characterized by the following signs and symptoms absence of periods hair loss headache excess facial hair pelvic pain acne Treatment:  Generally, this ailment is treated with hormonal therapies and medication.