Amenorrhea is the medical term for the absence of menstruation . There are two types of amenorrhea, primary and secondary. Primary amenorrhea refers to delayed menarche (the first menstrual period) and is defined as any one of three conditions:
- the absence of menarche by age 16 in a girl with otherwise normal pubertal development (development of breasts and/or pubic hair)
- the absence of menarche by age 14 combined with delayed pubertal development
- the absence of menarche two years after puberty is otherwise completed
Secondary amenorrhea is defined as the absence of menstruation after menarche has taken place. Although it is not uncommon for a girl's menstrual periods to be irregular during early adolescence , most girls' periods usually become regular within 18 months after the first one. After that time, it is considered abnormal for an adolescent to miss three consecutive periods.
Normal menstrual periods are the result of proper functioning and synchronization of the hypothalamus, pituitary gland, and ovaries. The hypothalamus is the part of the brain that controls body temperature, cellular metabolism, and such basic functions as appetite for food, the sleep/wake cycle, and reproduction. The hypothalamus also secretes hormones that regulate the pituitary gland. The pituitary gland in turn produces hormones that stimulate the ovaries to secrete two hormones known as estradiol and progesterone. These ovarian hormones encourage the growth of the endometrium, which is the tissue that lines the uterus. If pregnancy does not occur, the endometrium breaks down and the uterus sheds the extra tissue during the next menstrual period.
Amenorrhea can result from an interruption at any of several points in the normal cycle:
- The hypothalamus and pituitary may fail to produce enough hormone to stimulate the ovaries to produce their hormones.
- The ovaries may fail to produce enough estradiol to stimulate the growth of the endometrium.
- There may be structural abnormalities in the uterus, cervix, or vagina that prevent the shed tissue from leaving the body.
Secondary amenorrhea is more common in females in North America than primary amenorrhea. One study estimates that about 5 percent of menstruating women have an episode of secondary amenorrhea each year.
The average age for the onset of the menses in girls in the United States and Canada is 12.77 years. There is no evidence as of the early 2000s that the incidence of either primary or secondary amenorrhea is related to race or ethnic background.
Causes and symptoms
There are a number of possible causes of amenorrhea:
- Pregnancy: An adolescent with amenorrhea most likely does not have a serious underlying medical problem. All teenagers with amenorrhea should seek medical care, and an adolescent who has had sexual intercourse even once and then missed a period should assume she is pregnant until a reliable pregnancy test proves otherwise. It should be noted that spotting or even bleeding is not unusual during early pregnancy. In addition, it is possible for a girl to conceive before she has had even one period.
- Disorders of the hypothalamus or the pituitary gland: These problems may be associated with brain tumors.
- Ovarian disorders: These disorders may include premature ovarian failure or may be the side effects of chemotherapy or radiation therapy for cancer . Premature ovarian failure accounts for about 10 percent of cases of secondary amenorrhea.
- Hyperandrogenism: The overproduction of male hormones (androgens) by the girl's body can interrupt menstruation. Male hormones are produced in small quantities by all women, but some individuals produce excessive amounts, leading to such conditions as polycystic ovarian syndrome (PCOS), hirsutism (excessive growth of body hair), or abnormalities of the external genitalia. PCOS in adolescents is often triggered by obesity .
- Genetic disorders: Some genetic disorders that affect the X chromosome, such as Turner's syndrome, prevent normal sexual maturation in girls.
- Psychiatric disorders: Depression, obsessive-compulsive disorder , eating disorders, and schizophrenia can all cause disturbances of the menstrual cycle.
- Abuse of alcohol or other drugs: Excessive alcohol intake can lead to malnutrition , while cocaine and opioids (narcotics) can affect the menstrual cycle directly.
- Immunodeficiency disorders or conditions.
- Emotional stress: This disturbance can interfere with the brain's hormonal signals to the ovaries. It is not uncommon for a girl's period to be delayed when she is having problems with school, work, or relationships. A change in environment (the first year of college or taking a new job, for example) can also cause a young woman's period to be late.
- Female athlete triad: Female athletes at the high school or college level are at increased risk for a triad of disorders: excessive dieting or disordered eating, amenorrhea, and loss of bone minerals leading to osteoporosis. The triad was first formally named in 1993 but had been known to doctors for decades before. Girls who are involved in sports that emphasize weight control or a slender body build (gymnastics, track and field, cheerleading) are at greater risk than those who play field hockey, basketball, softball, or other sports that emphasize strength.
Amenorrhea may be associated with the symptoms of other disorders; for example, girls with an eating disorder will often have eroded tooth enamel, tiny pinpoint hemorrhages around the eyes, an abnormal heart rhythm, low blood pressure, and other signs of frequent vomiting . Girls whose amenorrhea is part of the female athlete triad may have a record of bone fractures or other evidence of bone mineral loss. Hot flashes and night sweats may indicate premature ovarian failure. Headaches or visual disturbances may suggest a brain tumor.
When to call the doctor
Girls who have not had a menstrual period by age 16 or who have not shown any signs of breast development or other indications of puberty by age 14 should be examined for causes of primary dysmenorrhea . Girls who have begun to menstruate and have missed three periods should be evaluated for secondary amenorrhea. If they are sexually active, they should have a pregnancy test after missing even one period.
History and physical examination
The first part of diagnosing amenorrhea is a careful history, including a record of medications and any surgical procedures involving the abdomen or genitals. The doctor will ask detailed questions about stress, dieting, sexual activity, and athletic participation, as well as questions about chronic diseases or disorders of the central nervous system. Family history should be taken into consideration in any adolescent with primary amenorrhea, as mothers who started to menstruate late will often have daughters who also menstruate late.
In the case of female athletes, the doctor may need to establish a relationship of trust with the patient before asking about such matters as diet, practice and workout schedules, and the use of such drugs as steroids or ephedrine. The presence of stress fractures in young women should be investigated. In some cases, the doctor may give the patient the Eating Disorder Inventory (EDI) or a similar screening questionnaire to help determine whether the patient is at risk for developing anorexia or bulimia.
The doctor will then perform a physical examination to evaluate the patient's weight in proportion to her height as well as her general nutritional status; to check for breast development, pubic hair, and other signs of normal female sexual development; to make sure the heart rhythm, blood pressure, and other vital signs are normal; and to palpate (feel) the thyroid gland for evidence of swelling. The physical examination may include a pelvic examination to check for abnormalities in the structure of the vagina or cervix.
To rule out specific causes of amenorrhea, the doctor may order a pregnancy test in sexually active young women as well as blood tests to check the level of thyroid hormone. Based on the initial test results, the doctor may want to perform additional tests to determine the level of other hormones that play a role in reproduction. A special type of blood test called a karyotype may be done to analyze the girl's chromosomes if the doctor suspects Turner's syndrome or another genetic disorder.
One way to determine whether a teenager's ovaries and uterus are functioning is a progesterone challenge test. In this test, an amenorrheic teenager is given a dose of progesterone either orally or as an injection. If her ovaries are producing estrogen and her uterus is responding normally, she should have a menstrual period within a few days of the progesterone dose. This challenge indicates that the ovaries and uterus are functioning normally, and the cause of the amenorrhea is probably in the brain.
In some cases the doctor may order an ultrasound study of the pelvic region to check for anatomical abnormalities or x rays or a bone scan to check for bone fractures. In some cases the doctor may order an MRI to rule out tumors affecting the hypothalamus or pituitary gland.
Teenagers whose amenorrhea may be related to depression, family stress, eating disorders, or other mental health issues may be referred to a psychiatrist for further evaluation.
The most frequent risk associated with amenorrhea is osteoporosis (thinning of the bone) caused by low estrogen levels. Because osteoporosis can begin as early as adolescence, hormone replacement therapy is sometimes recommended for teenagers with chronic amenorrhea.
Amenorrhea associated with hormonal, genetic, psychiatric, or immunodeficiency disorders may require a variety of different medications and other treatments administered by specialists. Tumors of the hypothalamus and the pituitary gland or abnormalities of the reproductive organs usually require surgery.
As with conventional medical treatments, alternative treatments are based on the cause of the condition. If a hormonal imbalance is revealed by laboratory testing, hormone replacements that are more natural for the body (including tri-estrogen and natural progesterone) are recommended. Glandular therapy can assist in bringing about a balance in the glands involved in the reproductive cycle, including the hypothalmus, pituitary, thyroid, ovarian, and adrenal glands.
Since homeopathy and acupuncture work on deep energetic levels to rebalance the body, these two forms of therapy may be helpful in treating amenorrhea. Western and Chinese herbal medicines also can be very effective. Herbs used to treat amenorrhea include dong quai ( Angelica sinensis ), black cohosh ( Cimicifuga racemosa ), and chaste tree ( Vitex agnus-castus ). Herbal preparations used to bring on the menstrual period are known as emmenagogues. For some adolescents, meditation, guided imagery, and visualization can play a key role in the treatment of amenorrhea by relieving emotional stress.
Diet and adequate nutrition , including adequate protein, essential fatty acids, whole grains, and fresh fruits and vegetables are important for every female past puberty, especially if deficiencies are present or if she regularly exercises very strenuously. Girls who are abusing alcohol or other drugs should be evaluated for possible malnutrition as part of treatment for substance abuse.
Female athletes at the high school or college level should consult a nutritionist to make sure that they are eating a well-balanced diet that is adequate to maintain a healthy weight for their height. Girls participating in dance or in sports that emphasize weight control or a slender body type (gymnastics, track and field, swimming, and cheerleading) are at higher risk of developing eating disorders than those that are involved in such sports as softball, weight lifting, or basketball. In some cases the athlete may be given calcium or vitamin D supplements to lower the risk of osteoporosis.
The prognosis of either primary or secondary amenorrhea depends on the underlying cause.
Amenorrhea related to pregnancy, the female athletic triad, drug or alcohol abuse, or eating disorders is preventable insofar as these are lifestyle choices. Primary or secondary amenorrhea associated with genetic mutations or other systemic diseases or disorders is not preventable.
Amenorrhea is a fairly dramatic symptom of menstrual dysfunction that often causes parents to consult a doctor about a girl's health. Parental concerns about amenorrhea, however, should be directed to the underlying cause. Amenorrhea related to emotional stress, dieting, or excessive exercise usually goes away when the stress is relieved or when the girl makes appropriate lifestyle adjustments. On the other hand, amenorrhea associated with glandular disturbances, tumors, genetic or anatomical abnormalities, diabetes, or other systemic disorders is part of a larger and more worrisome picture. Parents should discuss their concerns about the long-term effects of amenorrhea on the girl's health, whether she will be able to have children in adult life, and how they can help her manage her condition with the doctors, nutritionists, and other healthcare professionals who are treating her.
Anorexia nervosa —An eating disorder marked by an unrealistic fear of weight gain, self-starvation, and distortion of body image. It most commonly occurs in adolescent females.
Emmenagogue —A type of medication that brings on or increases a woman's menstrual flow.
Endometrium —The mucosal layer lining the inner cavity of the uterus. The endometrium's structure changes with age and with the menstrual cycle.
Female athlete triad —A combination of disorders frequently found in female athletes that includes disordered eating, osteoporosis, and oligo- or amenorrhea. The triad was first officially named in 1993.
Hyperandrogenism —The excessive secretion of androgens.
Menarche —The first menstrual cycle in a girl's life.
Osteoporosis —Literally meaning "porous bones," this condition occurs when bones lose an excessive amount of their protein and mineral content, particularly calcium. Over time, bone mass and strength are reduced leading to increased risk of fractures.
Turner syndrome —A chromosome abnormality characterized by short stature and ovarian failure caused by an absent X chromosome. It occurs only in females.
Diagnostic and Statistical Manual of Mental Disorders ,4th edition, Text Revision. Washington, DC: American Psychiatric Association, 2000.
"Menstrual Abnormalities and Abnormal Uterine Bleeding." Section 18, Chapter 235 in The Merck Manual of Diagnosis and Therapy , edited by Mark H. Beers and Robert Berkow. Whitehouse Station, NJ: Merck Research Laboratories, 2002.
Pelletier, Kenneth R. "CAM Therapies for Specific Conditions: Menstrual Symptoms, Menopause, and PMS." In The Best Alternative Medicine , Part II. New York: Simon and Schuster, 2002.
Gordon, C. M., and L. M. Nelson. "Amenorrhea and Bone Health in Adolescents and Young Women." Current Opinion in Obstetrics and Gynecology 15 (October 2003): 377–84.
Khalid, A. "Irregular or Absent Periods: What Can an Ultrasound Scan Tell You?" Best Practice and Research: Clinical Obstetrics and Gynaecology 18 (February 2004): 311.
Seidenfeld, Marjorie E. K., and Vaughn J. Rickert. "Impact of Anorexia, Bulimia and Obesity on the Gynecologic Health of Adolescents." American Family Physician 64 (August 1, 2001): 445–50.
Warren, M. P., and L. R. Goodman. "Exercise-Induced Endocrine Pathologies." Journal of Endocrinological Investigation 26 (September 2003): 873–78.
American Academy of Child and Adolescent Psychiatry. 3615 Wisconsin Avenue, NW, Washington, DC 20016–3007. Web site: http://www.aacap.org.
American College of Obstetricians and Gynecologists (ACOG). 409 12th Street, SW, PO Box 96920, Washington, DC 20090–6920. Web site: http://www.acog.org.
American College of Sports Medicine (ACSM). 401 West Michigan Street, Indianapolis, IN 46202–3233. Web site: http://www.acsm.org.
Barrow, Boone. "Female Athlete Triad." eMedicine , June 17, 2004. Available online at http://www.emedicine.com/sports/topic163.htm (accessed November 8, 2004).
Chandran, Latha. "Menstruation Disorders." eMedicine , August 9, 2004. Available online at http://www.emedicine.com/ped/topic2781.htm (accessed November 8, 2004).
Nelson, Lawrence M., et al. "Amenorrhea." eMedicine , August 9, 2004. Available online at http://www.emedicine.com/med/topic117.htm (accessed November 8, 2004).
Gail Slap, MD