Oligomenorrhea is the term for by light or infrequent menstrual periods. It occurs in women of childbearing age. Some variation in menstruation is normal. A woman who regularly goes more than 35 days without menstruating may be diagnosed with oligomenorrhea.Dec 23, 2013

Oligomenorrhea (or oligomenorrhoea) is infrequent (or, in occasional usage, very light) menstruation.More strictly, it is menstrual periods occurring at intervals of greater than 35 days, with only four to nine periods in a year. Also, menstrual periods should have been regularly established previously before the development of infrequent flow.[1] The duration of such events may vary.


Oligomenorrhea can be a result of prolactinomas (adenomas of the anterior pituitary). It may also be caused by thyrotoxicosis, hormonal changes inperimenopausePrader–Willi syndrome, and Graves disease. “Endurance exercises such as running or swimming can affect the reproductive physiology of women athletes. Female runners, swimmers and ballet dancers menstruate infrequently in comparison to nonatheletic women of comparable age or not at all (amenorrhea). The degree of menstrual abnormality is directly proportional to the intensity of the exercise. For example,  have shown menstrual irregularity is more common, and more severe among tennis players than among golfers” (modified by a student paper written by A. Lord) Breastfeeding has also been linked to irregularity of menstrual cycles due to hormones which delay ovulation.

Women with polycystic ovary syndrome (PCOS) are also likely to suffer from oligomenorrhea. PCOS is a condition in which excessive androgens (male sex hormones) are released by the ovaries. Women with PCOS show menstrual irregularities that range from oligomenorrhea and amenorrhea, to very heavy, irregular periods. The condition affects about 6% of premenopausal women and is related to excess androgen production.

Eating disorders can also result in oligomenorrhea. Although menstrual disorders are most strongly associated with Anorexia nervosaBulimia nervosa may also result in oligomenorrhea or amenorrhea. There is some controversy regarding the exact mechanism for the menstrual dysregulation, since amenorrhea may sometimes precede substantial weight loss in some anorexics; thus some researchers hypothesize that some as-yet unrecognized neuroendocrine phenomenon may be involved, and the menstrual irregularities may be related to the biological undergirding of the disorders, rather than a result of nutritional deficiencies.




Medical dictionaries define oligomenorrhea as infrequent or very light menstruation. Butphysicians typically apply a narrower definition, restricting the diagnosis of oligomenorrhea towomen whose periods were regularly established before they developed problems with infrequentflow. With oligomenorrhea, menstrual periods occur at intervals of greater than 35 days, with onlyfour to nine periods in a year.


True oligomenorrhea can not occur until menstrual periods have been established. In the UnitedStates, 97.5% of women have begun normal menstrual cycles by age 16. The complete absenceof menstruation, whether menstrual periods never start or whether they stop after having beenestablished, is called amenorrheaOligomenorrhea can become amenorrhea if menstruationstops for six months or more.

It is quite common for women at the beginning and end of their reproductive lives to miss or haveirregular periods. This is normal and is usually the result of imperfect coordination between thehypothalamus, the pituitary gland, and the ovaries. For no apparent reason, a few womenmenstruate (with ovulation occurring) on a regular schedule as infrequently as once every twomonths. 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 PCOSshow menstrual irregularities that range from oligomenorrhea and amenorrhea on the one hand tovery heavy, irregular periods on the other. The condition affects about 6% of premenopausalwomen and is related to excess androgen production.

Other physical and emotional factors also cause a woman to miss periods. These include:

  • emotional stress
  • chronic illness
  • poor nutrition
  • eating disorders such as anorexia nervosa
  • excessive exercise
  • estrogen-secreting tumors
  • illicit use of anabolic steriod drugs to enhance athletic performance

Professional ballet dancers, gymnasts, and ice skaters are especially at risk for oligomenorrheabecause they combine strenuous physical activity with a diet intended to keep their weightdown. Menstrual irregularities are now known to be one of the three disorders comprising the so-called “female athlete triad,” the other disorders being disordered eating and osteoporosisThetriad was first formally named at the annual meeting of the American College of Sports Medicinein 1993, but doctors were aware of the combination of bone mineral loss, stress fractures,eating disorders, and participation in women’s sports for several decades before the triad wasnamed. Women’s coaches have become increasingly aware of the problem since the early1990s, and are encouraging female athletes to seek medical advice.

Causes and symptoms

Symptoms of oligomenorrhea include:

  • menstrual periods at intervals of more than 35 days
  • irregular menstrual periods with unpredictable flow
  • some women with oligomenorrhea may have difficulty conceiving.

Oligomenorrhea that occurs in adolescents is often caused by immaturity or lack ofsynchronization between the hypothalamus, pituitary gland, and ovaries. The hypothalamus ispart of the brain that controls body temperature, cellular metabolism, and basic functions suchas eating, sleeping, and reproduction. It 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 maynot be synchronized, causing menstrual irregularities.

In PCOS, oligomenorrhea is probably caused by inappropriate levels of both female and malehormones. Male hormones are produced in small quantities by all women, but in women withPCOS, levels of male hormone (androgens) are slightly higher than in other women. Morerecently, however, some researchers are hypothesizing that the ovaries of women with PCOSare abnormal in other respects. In 2003, a group of researchers in London reported that there arefundamental differences between the development of egg follicles in normal ovaries and follicledevelopment in the ovaries of women with PCOS.

In athletes, models, actresses, dancers, and women with anorexia nervosa, oligomenorrheaoccurs because the ratio of body fat to weight drops too low.


History and physical examination

Diagnosis of oligomenorrhea begins with the patient informing the doctor about infrequentperiods. The doctor will ask for a detailed description of the problem and take a history of howlong it has existed and any patterns the patient has observed. A woman can assist the doctor indiagnosing the cause of oligomenorrhea by keeping a record of the time, frequency, length, andquantity of bleeding. She should also tell the doctor about any recent illnesses, includinglongstanding conditions like diabetes mellitusThe doctor may also inquire about the patient’sdiet, exercise patterns, sexual activity, contraceptive use, current medications, or past surgicalprocedures.

The doctor will then perform a physical examination to evaluate the patient’s weight inproportion to her height, to check for signs of normal sexual development, to make sure the heartrhythm and other vital signs are normal, and to palpate (feel) the thyroid gland for evidence ofswelling.

In the case of female athletes, the doctor may need to establish a relationship of trust with thepatient before asking about such matters as diet, practice and workout schedules, and the useof such drugs as steroids or ephedrine. The presence of stress fractures in young women shouldbe 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 fordeveloping anorexia or bulimia.

Laboratory tests

After taking the woman’s history, the gynecologist or family practitioner does a pelvicexamination and Pap test. To rule out specific causes of oligomenorrhea, the doctor may alsodo a pregnancy test and blood tests to check the level of thyroid hormone. Based on the initialtest results, the doctor may want to do tests to determine the level of other hormones that play arole in reproduction.

As of 2003, more sensitive monoclonal assays have been developed for measuring hormonelevels in the blood serum of women with PCOS, thus allowing earlier and more accuratediagnosis.

Imaging studies

In some cases the doctor may order an ultrasound study of the pelvic region to check foranatomical abnormalities, or x rays or a bone scan to check for bone fractures. In a few casesthe doctor may order an MRI to rule out tumors affecting the hypothalamus or pituitary gland.

Oligomenorrhea is a medical term which generally refers to irregular or infrequentmenstrual periods with intervals of more than 35 days – however, the duration may vary. 

A period, or menstruation, is the shedding of the endometrium – the lining of the uterus. Menstruation is also called menses. All female humans, as well as a number of other female mammals, have regular periods during their reproductive age. Menstruation, which includes bleeding from the vagina, occurs mainly among humans and similar animals, such as primates. In many mammals, the endometrium is reabsorbed. 

As far as humans are concerned a period is a bleed from the womb (uterus) that is released through the vagina. Human females have a period about every 28 days – most women have between 11 and 13 menstrual periods each year. However, some women may have a 24-day cycle while other may have a 35-day one. A period is part of the female’s menstrual cycle. 

Periods usually start between the ages of 10 and 16 (during 
puberty), and continue until themenopause, when woman is 45 to 55 years old. Periods can take up to two years to occur in a regular cycle. After puberty, the majority of females have a regular menstrual cycle (the length of time between each period is similar). 

Menstrual bleeding usually lasts for about five days, but can vary from two to seven days. 

Some women have irregular periods – the time between periods, as well as the amount of blood shed varies considerably. This may have several possible causes, including a change in
contraception method, a hormone imbalance, hormonal changes in perimenopause, and endurance exercises. 

Treatments for irregular periods during puberty and around the menopause are not usually necessary, as they are quite common.                                                        
What are the causes of irregular periods?

There are two main reasons for irregular periods:

  • A change in the contraception method
  • An estrogen and/or progesterone imbalance (hormones which regulate the menstrual cycle)
  • Polycystic ovarian syndrome (polycystic ovary system) – also known as PCOS, or the Stein-Leventhal Syndrome. Many cysts (small, fluid filled sacs) develop in the ovaries. It is a condition characterized by irregular or no periods, obesityacne, and excess hair growth. 

    Women with PCOS have a disorder of chronically abnormal ovarian function and abnormally high levels of androgen (hyperandrogenism). Androgen is a male sex hormone – the major androgen is testosterone

    According to the CDC (Centers for Disease Control and Prevention), USA, approximately 5% to 10% of women of reproductive age are affected by PCOS. 

    A woman with PCOS does not release an egg every month (she does not ovulate). Patients with PCOS have a considerably higher risk of hypertension (high blood pressure),diabetesheart disease and endometrial cancer (cancer of the uterus). Experts say that in many cases weight loss and exercise can eliminate much of the risk.
  • A woman’s imbalance of hormones, which may lead to irregular periods, may also be caused by: 

    • Extreme weight loss. Low body weight is a common cause of irregular or missed periods.
    • Extreme weight gain. Obesity may sometimes cause menstrual problems.
    • Emotional stress
    • Eating disorders, such as anorexia or bulimia can lead to hormone imbalances, resulting in irregular or missed periods.
    • Endurance exercises – endurance athletes, such as those that compete in marathons, may have irregular or missed periods.
  • Age

    • Puberty – irregular periods for a few years after puberty are common, and not considered unusual. It may take a few years for the hormones that control menstruation – estrogen and progesterone – to reach a balance.
    • Before the menopause – as the menopause approaches women commonly have irregular periods. The amount of blood shed may also vary. Menopause occurs when it has been 12 months since the woman has had a menstrual period.
  • Breast feeding – most women do not start having periods again until they stop breastfeeding.
  • Thyroid disorder – irregular periods may be caused by a thyroid disorder. The thyroid gland produces hormones that affect our bodies’ metabolism.
  • Contraceptives – an IUD (intrauterine device) may cause heavy bleeding, while the contraceptive pill can cause spotting between periods. Initially, when using the contraceptive pill for the first time, it is not uncommon for the woman to experience breakthrough bleeds (small bleeds). Breakthrough bleeds are generally shorter and lighter than normal periods – they usually go away after a few months.
  • Cancer – bleeding between periods may be caused by cervical cancer or uterine cancer (cancer of the uterus/womb). These cancers may also cause the woman to bleed during sex. Bleeding caused by these cancers is rare.
  • Emdometriosis – this is a condition in which cells that are normally found inside the uterus (endometrial cells) are found growing outside it. That is, the lining of the inside of the uterus is found outside of it. Endometrial cells are the cells that shed every month during menstruation, and so endometriosis is most likely to affect women during their childbearing years. The cellular growth is not cancerous, but benign. Though there are not always symptoms, it can be painful and lead to other problems. 

    Problems may occur if released blood gets stuck in surrounding tissue and damage it, causing severe pain, irregular periods and infertility.
  • Pelvic inflammatory disease – an infection of the female reproductive system. It is the most common and serious complication of sexually transmitted diseases, apart from AIDS, among women. If detected early it can be treated with antibiotics. However, if it spreads and damages the fallopian tubes and uterus it can result in chronic episodes of pain (in medicine “chronic” means long-term, for life). Of the many symptoms are included bleeding between periods and after sex.


What are the treatment options for irregular periods?

If the irregular periods occur during puberty or as the woman approaches the menopause, treatment is not usually necessary.

  • Contraception – any patient who has been fitted with an IUD (intrauterine device) and has been having irregular bleeding that does not go away after a few months should talk to a health care professional and discuss alternative contraception options. 

    Women who are on a new contraceptive pill that is causing irregular bleeding for more than a couple of months will probably be advised to switch to another pill.
  • PCOS (polycystic ovarian syndrome) – if the woman is overweight/obese and has PCOS, as well as irregular periods, losing weight may help resolve the irregular periods. On losing weight the body does not need to produce so much insulin, resulting in lower testosterone levels and a better chance of ovulating. 

    If the woman is not trying to become pregnant, the doctor may prescribe low-dose birth control pills that contain a combination of estrogen and progesterone (synthetic). They lower androgen (male hormone) production and give the body a rest from the effect of non-stop estrogen, lowering the risk of endometrial cancer, as well as correcting abnormal bleeding. 

    Alternatively, the woman may take progesterone for about 10 to 14 days each month – this is likely to regulate the periods, as well as offering protection against endometrial cancer (does not improve androgen levels). 

    The doctor may prescribe metformin (Glucophage, Glucophage XR) – this is an insulin-lowering oral drug for type 2 diabetes, resulting in more probable ovulation and regular periods. The medication also slows down the progression of type 2 diabetes if the patient already has pre-diabetes and subsequently loses weight.
  • Thyroid problems – treatment may involve: 

    • Prescribing medication that slows down the production of thyroid hormones.
    • Radioactive iodine therapy – radioiodine treatment is a kind of radiotherapy that targets tissue in the thyroid gland, resulting in a reduction in the amount of thyroid hormone the thyroid gland produces.
    • Partial thyroidectomy – part of the thyroid gland is surgically removed.
  • Psychological therapy – if emotional stress or sudden weight loss are diagnosed as a cause of irregular periods, the doctor may advise counseling or stress management. This may include relaxation techniques, stress management, and talking to a therapist.
  • Treatment

    Treatment of oligomenorrhea depends on the cause. In adolescents and women nearmenopauseoligomenorrhea usually needs no treatment. For some athletes, changes intraining routines and eating habits may be enough to return the woman to a regular menstrualcycle.
    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 whichparticular hormones are deficient or out of balance. When oligomenorrhea is associated with aneating disorder or the female athlete triad, the underlying condition must be treated. Consultationwith a psychiatrist and nutritionist is usually necessary to manage an eating disorder. Femaleathletes may require physical therapy or rehabilitation as well.

    Alternative treatment

    As with conventional medicial treatments, alternative treatments are based on the cause of thecondition. If a hormonal imbalance is revealed by laboratory testing, hormone replacements thatare more “natural” for the body (including tri-estrogen and natural progesterone) arerecommended. Glandular therapy can assist in bringing about a balance in the glands involved inthe 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 modalities may be helpful in treating oligomenorrhea. Western and Chinese herbalmedicines also can be very effective. Herbs used to treat oligomenorrhea 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. Forsome women, meditationguided imagery, and visualization can play a key role in thetreatment of oligomenorrhea by relieving emotional stress.
    Diet and adequate nutrition, including adequate protein, essential fatty acids, whole grains, andfresh fruits and vegetables, are important for every woman, especially if deficiencies are presentor if she regularly exercises very strenuously. Female athletes at the high school or college levelshould consult a nutritionist to make sure that they are eating a well-balanced diet that isadequate to maintain a healthy weight for their height. Girls participating in dance or in sportsthat 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 insuch sports as softball, weight lifting, or basketball. In some cases the athlete may be givencalcium or vitamin D supplements to lower the risk of osteoporosis.
    Many women, including those with PCOS, are successfully treated with hormones foroligomenorrhea. They have more frequent periods and begin ovulating during their menstrualcycle, restoring their fertility.
    For women who do not respond to hormones or who continue to have an underlying conditionthat causes oligomenorrhea, the outlook is less positive. Women who have oligomenorrhea mayhave difficulty conceiving children and may receive fertility drugs. The absence of adequateestrogen increases risk for bone loss (osteoporosis) and cardiovascular disease. Women who donot have regular periods also are more likely to develop uterine cancerOligomenorrhea canbecome 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 themfrom maintaining a regular menstrual cycle. Adequate nutrition and a less vigorous trainingschedules will normally prevent oligomenorrhea. When oligomenorrhea is caused by hormonalfactors, it is not preventable, but it is often treatable.

    Key terms

    Anorexia nervosa — A disorder of the mind and body in which people starve themselves in adesire to be thin, despite being of normal or below normal body weight for their size and age.
    Cyst — An abnormal sac containing fluid or semisolid material.
    Emmenagogue — A medication or herbal preparation given to bring on a woman’s menstrualperiod.
    Female athlete triad — A combination of disorders frequently found in female athletes thatincludes disordered eating, osteoporosis, and oligo- or amenorrhea. The triad was first officiallynamed in 1993.
    Osteoporosis — The excessive loss of calcium from the bones, causing the bones to becomefragile and break easily. Women who are 


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