Amenorrhea (missed periods) is the absence of menstrual bleeding. In females of reproductive age, diagnosing amenorrhea is a matter of first determining whether pregnancy is the cause for this condition. If pregnancy is not present, the challenge is finding the exact cause of the absent periods. The problem may be either primary or secondary. Primary amenorrhea is a delay in or a failure to start menstruation; secondary amenorrhea is an unexpected cessation of the menstrual cycle.

Normal menstrual cycles rely on a complex feedback system between the hypothalamus, the pituitary gland, the ovaries, and the cyclical reaction of the lining in the uterus to sex hormones (See graphic).

Thus the hormonal system has a major part to play in the development of this condition, with doctors usually prescribing hormone therapy to regulate menstrual cycles.

Actually, amenorrhea is just a symptom; the underling problem can arise from multiple factors, and individuals can present with various forms of associated symptoms. For example, individuals with hormone disorders may have excessive body and facial hair, acne, unusual breast secretions, dry skin, sensitivity to cold temperatures, a change in voice or sex drive, weight gain, or weight loss.

You should consult a gynecologist if your first menses have not come by age sixteen. For secondary cases, if missed periods are not due to physiological factors such as pregnancy or menopause, and last for more than three cycles, you should also seek medical advice.

During consultation, doctors will obtain a detailed history and perform a physical exam. Investigations like blood tests, x-rays, ultrasound scans, as well as chromosome testing may also be necessary. The following are frequently asked on the first visit:

Amenorrhea is rarely caused by a life-threatening condition. In most secondary cases, the underlying problems are reversible and treatable; treatments include oral supplemental hormones, surgery or simply a change in lifestyle.