Amenorrhoea

Abnormal absence or arrest of menstruation. There are two categories of this disorder. Primary amenorrhoea is the failure to begin menstruating by the age of 16. Secondary amenorrhoea, the more common of the two conditions, is the absence of three or more periods in a row in a women who has been menstruating for some time

Persons most commonly affected: Primary amenorrhoea affects young girls.
Organ or part of body involved: Female reproductive system.
Symptoms and indications: Primary amenorrhoea is commonly accompanied by abnormal or inhibited physical development; the young girl may fail to develops or body hair, indicating that a genetic disorder may be preventing her from attaining sexual maturity. These girls are usually short in height. Secondary amenorrhoea has no symptoms other that the absence of menstrual periods.
Causes and risk factors: Primary amenorrhoea may be caused by an endocrine gland disorder (such as hyperthyroidism), genetic abnormalities, damaged or missing ovaries, uterus or vagina, or an excessive thick hymen, which blocks the outflow of the menstrual discharge. Secondary amenorrhoea is caused most commonly by pregnancy. It can also be triggered by strenuous sports training, poor nutrition, drastic weight gain, jet lag, certain medications (including corticosteroids, tranquilizers and birth control pills), major surgery, emotional shock or the loss of a large percentage of body fat.
Prevention: Maintaining good nutritional habits and normal weight and avoiding over strenuous sports can probably be beneficial in preventing secondary amenorrhoea. No specific precautions can be taken, however, to prevent primary amenorrhoea but avoid smoking, alcohol and stress.