Amenorrhea

The absence or abnormal ceasing (stoppage) of menstrual periods. The absence of cyclical menstruation, amenorrhea, most frequently reflects an abnormality in hypothalamic/pituitary and/or ovarian function. Central amenorrhea can be caused by disease of the brain or pituitary gland. The former may be rarely due to a genetic defect or more commonly to acquired disease leading to a deficit in the production of GnRH, which controls the secretion of pituitary gonadotropins. Changes in body mass, stress (both physical and psychological), and drug abuse may cause hypothalamic amenorrhea due to brain dysfunction.

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