Failure to menstruate may cause the uterine lining to thicken putting you at risk for cancers.
A young woman has reached the age of 16 (in some texts 18) and has not begun menstruating.
Oligomenorrhea or secondary amenorrhea
A woman who has started menses but has missed menstrual cycles for three consecutive months.
Secondary amenorrhea often occurs with extreme exercise such as long-distance running. Typically, leaner women have higher levels of protein which affect estrogen; therefore, less free estrogen is available to stimulate the reproductive cycle properly. Other specific causes include stress, nutritional inadequacies, hormonal imbalances, tumors, intrauterine infection, endometriosis, discontinuation of oral contraceptives, diseases such as diabetes mellitus or tuberculosis, anorexia nervosa, or obesity.