Definition

Menstruation, or a menstrual period, refers to the monthly process in which the uterus sheds blood and tissue to prepare for pregnancy.

Not having or missing a menstrual period is called amenorrhea. This condition is divided into two types:

• Primary amenorrhea—when an adolescent female has not yet begun menstruation by around age 16 years
  • Most females begin menstruating between the ages 9-18, but age 12 is the average.
• Secondary amenorrhea—when a woman who has previously menstruated misses three or more periods in a row

Causes

The most common cause of secondary amenorrhea is pregnancy. In nonpregnant women, it may be due to a variety of factors.

Risk Factors

Factors that may increase the risk of amenorrhea include:

• Dramatic weight loss (such as from extreme diets, eating disorders, or excessive exercise) or dramatic weight gain
• Malnutrition
• Birth defects, including lack of female reproductive organs
• Chromosomal or hormonal abnormalities
• Certain conditions such as thryoid disorder and pituitary tumor
• Medications such as certain contraceptives
• Emotional distress
• Uterine scarring

Symptoms

The main symptom for primary amenorrhea is the absence of a menstrual period in a female by age 16 or older. The main symptom for secondary amenorrhea is three or more missed periods in a row in a woman who has previously had menstrual periods.

Diagnosis

You will be asked about your symptoms and medical history. A physical exam will be done.

Your bodily fluids may be tested. This can be done with:

• Blood tests
• Urine tests

Images may be taken of your bodily structures. This can be done with:

• MRI scan
• Ultrasound

Treatment

Treatment will depend on what is causing amennorhea. Examples include:

• Weight-related cause—A healthy caloric intake and exercise routine usually restores hormonal balance and menstruation.
• Birth defect—Surgery may be needed.
• Hormonal irregularity—Hormanal therapy may be needed.
• Emotional distress—Relaxation techniques, therapy, and exercise may help to decrease stress.
• Pituitary tumor—Surgery, radiation therapy, or medication may be needed.

Prevention

Amenorrhea may or may not be preventable, depending on the cause. Follow these general guidelines to prevent amenorrhea:

• Maintain an appropriate level of body fat.
• Get help for an eating disorder.
• Treat conditions that can lead to amenorrhea, such as polycystic ovary syndrome, pituitary tumor, and hypothyroidism.

Women’s Health—US Department of Health and Human Services http://www.womenshealth.gov

The Society of Obstetricians and Gynaecologists of Canada http://www.sogc.org

Amenorrhea. Family Doctor—American Academy of Family Physicians website. Available at:
http://familydoctor.org/familydoctor/en/diseases-conditions/amenorrhea.html
Updated February 2014. Accessed August 8, 2014.

Current evaluation of amenorrhea. American Society for Reproductive Medicine website. Available at:
http://www.asrm.org/uploadedFiles/ASRM_Content/News_and_Publications/Practice_Guidelines/Educational_Bulletins/Current_evaluation(1).pdf
Accessed August 8, 2014.