Medical dictionaries define oligomenorrhea as infrequent or very light
. But physicians typically apply a narrower definition, restricting the
diagnosis of oligomenorrhea to women whose periods were regularly
established before they developed problems with infrequent flow. With
oligomenorrhea, menstrual periods occur at intervals of greater than 35
days, with only four to nine periods in a year.
True oligomenorrhea cannot occur until a young woman's menstrual
periods have been established. In the United States, 97.5 percent of women
have begun normal menstrual cycles by age 16. The complete absence of
menstruation (menstrual periods never started or they stopped after having
been established) is called
. Oligomenorrhea can be redefined as amenorrhea if menstruation stops for
six months or more; however, there is no universally agreed-upon cutoff
point or timeline.
It is quite common for women at the beginning and end of their
reproductive lives to miss periods or have them at irregular intervals.
This variation is normal and is usually the result of imperfect
coordination between the hypothalamus, the pituitary gland, and the
ovaries. For no apparent reason, a few women menstruate (with ovulation
occurring) on a regular schedule as infrequently as once every two months.
For them that schedule is normal and not a cause for concern.
Women with polycystic ovary syndrome (PCOS) are also likely to suffer from
oligomenorrhea. PCOS is a condition in which the ovaries become filled
with small cysts. Women with PCOS show menstrual irregularities that range
from oligomenorrhea and amenorrhea to very heavy and irregular periods.
PCOS affects about 6 percent of premenopausal women and is related to
excess androgen production.
Other physical and emotional factors also cause a woman to miss periods.
These include the following:
Professional ballet dancers, gymnasts, and ice skaters are especially at
risk for oligomenorrhea because they combine strenuous physical activity
with a diet intended to keep their weight down. Menstrual irregularities
are known to be one of the three disorders comprising the so-called
"female athlete triad," the other disorders being disordered
eating and osteoporosis. The triad was first formally named at the annual
meeting of the American College of Sports Medicine in 1993, but doctors
were aware of the combination of bone mineral loss, stress
, eating disorders, and participation in women's
for several decades before the triad was named. Women's coaches
have become increasingly aware of the problem since the early 1990s and
are encouraging female athletes to seek medical advice.
By definition, oligomenorrhea is a health concern only for women. It is
estimated that about 5 percent of women in the United States in their
childbearing years experience an episode of oligomenorrhea each year. This
percentage appears to be constant across racial and ethnic groups.
Oligomenorrhea related to the female athlete triad is more common in this
group of women than in the general female population. One study at the
University of California at San Francisco found that 11 percent of female
marathon runners had amenorrhea or oligomenorrhea. Although precise data
are difficult to obtain because many athletes with the triad try to hide
their symptoms from others, disordered eating and menstrual irregularities
have been estimated to run as high as 62 percent of female athletes at the
college level, with 4 percent to 39 percent meeting the criteria for
anorexia nervosa or
as defined by the fourth edition of the
Diagnostic and Statistical Manual of Mental Disorders
Causes and symptoms
Oligomenorrhea that occurs in adolescents is often caused by immaturity or
lack of synchronization between 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 is then stimulated to produce hormones that affect
growth and reproduction. At the beginning and end of a woman's
reproductive life, some of these hormone messages may not be synchronized,
resulting in menstrual irregularities.
Oligomenorrhea in PCOS is thought to be caused by inappropriate levels of
both female and male hormones. Male hormones are produced in small
quantities by all women, but in women with PCOS, levels of male hormone
(androgens) are slightly higher than in other women. Some researchers
hypothesize that the ovaries of women with PCOS are abnormal in other
respects. In 2003, a group of researchers in London reported that there
are fundamental differences between the development of egg follicles in
normal ovaries and follicle development in the ovaries of women with PCOS.
In athletes, models, actresses, dancers, and women with anorexia nervosa,
oligomenorrhea occurs because body fat drops too low compared to weight.
Emotional stress related to performance anxiety may also be a factor in
oligomenorrhea in these women.
Women with oligomenorrhea may have the following symptoms:
Young women whose oligomenorrhea is associated with the female athlete
triad may have such other symptoms of the triad as frequent stress
fractures, particularly in the bones of the hips, spine, or lower legs;
abnormal eating patterns or extremely restrictive diets; and abnormal
heart rhythms or low blood pressure.
A young woman should see her doctor as soon as she notices that a
previously regular menstrual pattern has become irregular; it is not
necessary to wait six months or longer to have oligomenorrhea
investigated. A common rule is to consult the doctor after three missed
Diagnosis of oligomenorrhea begins with the patient informing the doctor
about infrequent periods. The doctor will ask for a detailed description
of the problem and take a history of how long it has existed and any
patterns the patient has observed. A woman can assist the doctor in
diagnosing the cause of oligomenorrhea by keeping a record of the time,
frequency, length, and quantity of bleeding. She should also tell the
doctor about any recent illnesses, including longstanding conditions such
. The doctor may also inquire about the patient's diet, exercise
patterns, sexual activity, contraceptive use, current medications, or past
The doctor will then perform a physical examination to evaluate the
patient's weight in proportion to her height, to check for signs of
normal sexual development, to make sure the heart rhythm and other vital
signs are normal, and to palpate (feel) the thyroid gland for evidence of
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 patients
the Eating Disorder Inventory (EDI) or a similar screening questionnaire
to help determine whether the patient is at risk for developing anorexia
After taking the young woman's history, the gynecologist or
practitioner does a pelvic examination and Pap smear. To rule out
specific causes of oligomenorrhea, the doctor may also order a pregnancy
test in sexually active women and 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.
As of 2003, more sensitive monoclonal assays had been developed for
measuring hormone levels in the blood serum of women with PCOS, thus
allowing earlier and more accurate diagnosis.
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 a few cases the doctor may order an MRI to
rule out tumors affecting the hypothalamus or pituitary gland.
Treatment of oligomenorrhea depends on the cause. In adolescents and women
near menopause, oligomenorrhea usually needs no treatment. For some
athletes, changes in training routines and eating habits may be enough to
return the woman to a regular menstrual cycle.
Most patients suffering from oligomenorrhea are treated with birth control
pills. Other women, including those with PCOS, are treated with hormones.
Prescribed hormones depend on which particular hormones are deficient or
out of balance. When oligomenorrhea is associated with an eating disorder
or the female athlete triad, the underlying condition must be treated.
Consultation with a psychiatrist and nutritionist is usually necessary to
manage an eating disorder. Female athletes may require physical therapy or
rehabilitation as well.
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 hypothalamus, pituitary, thyroid, ovarian, and adrenal
Since homeopathy and acupuncture work on deep, energetic levels to
rebalance the body, these two forms of therapy may be helpful in treating
oligomenorrhea. Western and Chinese herbal medicines also can be very
effective. Herbs used to treat oligomenorrhea include dong quai (
), black cohosh (
), and chaste tree (
). Herbal preparations used to bring on the menstrual period are known as
emmenagogues. For some women, meditation, guided imagery, and
visualization can play a role in the treatment of oligomenorrhea by
relieving emotional stress.
Diet and adequate
, including adequate protein, essential fatty acids, whole grains, and
fresh fruits and vegetables are important for every woman, especially if
deficiencies are present or if she regularly exercises very strenuously.
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.
Many women, including those with PCOS, are successfully treated with
hormones for oligomenorrhea. They have more frequent periods and begin
ovulating during their menstrual cycle, restoring their fertility.
For women who do not respond to hormones or who continue to have an
underlying condition that causes oligomenorrhea, the outlook is less
positive. Women who have oligomenorrhea as teenagers may have difficulty
becoming pregnant and may receive fertility drugs. The absence of adequate
estrogen increases the risk of osteoporosis, repeated bone fractures, and
cardiovascular disease in later life. Female athletes who develop bone
loss or osteoporosis in their late teens or early twenties are at
increased risk of developing arthritis as they grow older. Women who do
not have regular periods also are more likely to develop uterine
. Oligomenorrhea can become amenorrhea at any time, increasing the chance
of having these complications.
Oligomenorrhea is preventable only in women whose low body fat to weight
ratio is keeping them from maintaining a regular menstrual cycle. Adequate
nutrition and less vigorous training schedules for female athletes will
normally prevent oligomenorrhea. When oligomenorrhea is caused by hormonal
factors, however, it is not preventable, but is usually treatable.
—The absence or abnormal stoppage of menstrual periods.
—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.
—An abnormal sac or enclosed cavity in the body filled with
liquid or partially solid material. Also refers to a protective,
walled-off capsule in which an organism lies dormant.
—A type of medication that brings on or increases a
woman's menstrual flow.
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.
—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.
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3615 Wisconsin Avenue, NW, Washington, DC 20016–3007. Web site:
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401 West Michigan Street, Indianapolis, IN 46202–3233. Web site:
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