Menstruation, cessation of: The ending of a woman's menstrual cycles. Menstruation ends naturally in middle age with the onset of menopause. It can also end suddenly as a result of induced menopause. Cessation of menstruation in nonmenopausal women may be due to pregnancy, illness, disorders of the hypothalamus or pituitary gland, medication, stress, overexercise, or malnutrition, among other causes. In particular, it can be a symptom of anorexia, signaling potentially dangerous changes in the body's hormonal system. Cessation of menstruation in women who have established a regular menstrual cycle, or in girls or teens who show other signs of anorexia, is a cause for medical concern. Also known as amenhorrhea.