premenstrual

premenstrual syndrome (PMS)

Variable group of symptoms occurring before menstruation in 40percnt of women, severe in about 10percnt of those. Physical symptoms may include headache, cramps, bloating, and constipation or diarrhea. Emotional symptoms range from irritability, lethargy, and mood swings to hostility, confusion, and depression. Theories as to the cause centre on hormones, nutrition, and stress (known to affect severity). Depending on the symptoms, treatment may involve exercise, stress management, nutritional therapy, or drugs. Dietary measures include low sodium and high protein and complex carbohydrate intake and avoidance of xanthines (including caffeine). Increasing calcium intake has been shown to prevent or reduce cramps, which are best treated with ibuprofen.

Learn more about premenstrual syndrome (PMS) with a free trial on Britannica.com.

Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.

Premenstrual syndrome

Premenstrual syndrome (PMS) (sometimes referred to as PMT or Premenstrual Tension) is a collection of physical, psychological, and emotional symptoms related to a woman's menstrual cycle. While most women of child-bearing age (about 80 percent) have some Premenstrual symptoms, women with PMS have symptoms of "sufficient severity to interfere with some aspects of life". Such symptoms are usually predictable and occur regularly during the two weeks prior to menses. The symptoms may vanish after the menstrual flow starts, but may continue even after the flow has begun.

For some women with PMS, the symptoms are so severe that they are considered disabling. This form of PMS has its own psychiatric designation: premenstrual dysphoric disorder (PMDD).

Culturally, the abbreviation PMS is widely understood in the United States to refer to difficulties associated with menses, and the abbreviation is used frequently even in casual and colloquial settings, without regard to medical rigor. In these contexts, the syndrome is rarely referred to without abbreviation, and the connotations of the reference are frequently more broad than the clinical definition.

Symptoms

PMS is a collection of symptoms. More than 200 different symptoms have been identified, but the three most prominent symptoms are irritability, tension, and dysphoria (unhappiness). The exact symptoms and their intensity vary from woman to woman. Most women with premenstrual syndrome experience only a few of the problems. The following symptoms can also be attributed to PMS:

Abdominal bloating
Abdominal cramps
Breast tenderness or swelling
Stress or anxiety
Trouble falling asleep (insomnia)
Joint or muscle pain
Headache
Fatigue
Acne
Mood swings
Worsening of existing skin disorders, and respiratory (eg, allergies, infection) or eye (bulbar disturbances, conjunctivitis) problems

Risk factors

High caffeine intake
Stress may precipitate condition
Increasing age
History of depression
Tobacco use
Family history
Dietary factors (Low levels of certain vitamins and minerals, particularly magnesium, manganese, and vitamin E)

Family history is often a good predictor of the probability of premenstrual syndrome; studies have found that the occurrence of PMS is twice as high among identical twins compared with fraternal twins. Although the presence of premenstrual syndrome is high among women with affective disorders such as depression and bipolar disorder, a causal relationship has not been established.

Vitamin B can also assist with unstable emotions.

Diagnosis

There is no laboratory test or unique physical findings to verify the diagnosis of PMS. To establish a pattern, a woman's physician may ask her to keep a prospective record of her symptoms on a calendar for at least two menstrual cycles. This will help to establish if the symptoms are, indeed, premenstrual and predictably recurring. A number of standardized instruments have been developed to describe PMS, including the Calendar of Premenstrual syndrome Experiences (COPE), the Prospective Record of the Impact and Severity of Menstruation (PRISM), and the Visual Analogue Scales (VAS).

In addition, other conditions that may explain symptoms better must be excluded. A number of medical conditions are subject to exacerbation at menstruation, a process called menstrual magnification. These conditions may lead the patient to believe that she may have PMS, when the underlying disorder may be some other problem. A key feature is that these conditions may also be present outside of the luteal phase. Conditions that can be magnified perimenstrually include depression, migraine, seizure disorders, chronic fatigue syndrome, irritable bowel syndrome, asthma, and allergies.

Although there is no universal agreement about what qualifies as PMS, two definitions are commonly used in research programs:

The National Institute of Mental Health research compares the intensity of symptoms from cycle days 5 to 10 to the six-day interval before the onset of menses. To qualify as PMS, symptom intensity must increase at least 30% in the six days before menstruation. Additionally, this pattern must be documented for at least two consecutive cycles.

The definition formulated at the University of California at San Diego requires both affective (emotional) and somatic (physical) symptoms during the five days before menses in each of three consecutive cycles, and must not be present during the pre-ovulatory part of the cycle (days 4 through 13). For this definition, affective symptoms include symptoms like depression, angry outbursts, irritability, anxiety, confusion, and social withdrawal. Somatic symptoms include symptoms like breast tenderness, abdominal bloating, headache, and swelling of hands and feet.

Etiology (Causes)

The exact causes of PMS are not fully understood. While PMS is linked to the luteal phase, measurements of sex hormone levels are within normal levels. PMS tends to be more common among twins, suggesting the possibility of some genetic component. Current thinking suspects that central-nervous-system neurotransmitter interactions with sex hormones are affected. It is thought to be linked to activity of serotonin (a neurotransmitter) in the brain.

Genetic factors also seem to play a role, as the concordance rate is two times higher in monozygotic twins than in dizygotic twins. Preliminary studies suggest that up to 40% of women with symptoms of PMS, have a significant decline in their circulating serum levels of beta-endorphin. Beta endorphin is a naturally occurring opioid neurotransmitter which has an affinity for the same receptor that is accessed by heroin and other opiates. Some researchers have noted similarities in symptom presentation between PMS symptoms and opiate withdrawal symptoms.

Treatment

Many treatments have been suggested for PMS, including diet or lifestyle changes, and other supportive means. Medical interventions are primarily concerned with hormonal intervention and use of selective serotonin reuptake inhibitors (SSRIs).

Supportive therapy includes evaluation, reassurance, and informational counseling, and is an important part of therapy in an attempt to help the patient regain control over her life. In addition, aerobic exercise has been found in some studies to be helpful. Some PMS symptoms may be relieved by leading a healthy lifestyle: Reduction of caffeine, sugar, and sodium intake and increase of fiber, and adequate rest and sleep.

Dietary intervention studies indicate that calcium supplementation (1200 mg/d) may be useful. Also vitamin E (400 IU/d) has shown some effectiveness. A number of other treatments have been suggested, although research on these treatments is inconclusive so far: Vitamin B6, magnesium, manganese and tryptophan.

SSRIs can be used to treat severe PMS. The drug most widely studied is fluoxetine at doses of 20-60 mg/d. Other drugs include sertraline, paroxetine, clomipramine, fluvoxamine, and nefadozone. These drugs can also be given intermittently, that is when symptoms are expected to occur. Although intermittent therapy might be more acceptable to some women, this might be less effective than continuous regimens.

Hormonal intervention may take many forms:

Hormonal contraception is commonly used; common forms include the combined oral contraceptive pill and the contraceptive patch.
Progesterone support has been used for many years but evidence of its efficacy is inadequate.

Gonadotropin-releasing hormone agonists can be useful in severe forms of PMS but have their own set of significant potential side effects.

Diuretics have been used to handle water retention. Spironolactone has been shown in some studies to be useful.
Non-steroidal anti-inflammatory drugs (NSAIDs; eg ibuprofen) have been used.
Evening Primrose Oil, which contains gamma-Linolenic acid (GLA), has been advocated but lacks scientific support.
Clonidine has been reported to successfully treat a significant number of women whose PMS symptoms coincide with a steep decline in serum beta-endorphin on a monthly basis.

Prognosis

PMS is generally a stable diagnosis, with susceptible women experiencing the same symptoms at the same intensity near the end of each cycle for years.

Treatment for specific symptoms is usually effective at controlling the symptoms. Even without treatment, symptoms tend to decrease in perimenopausal women, and disappear at menopause.

Women who have PMS have an increased risk for clinical depression.

Epidemiology

The number of women who experience PMS depends entirely on the stringency of the definition of PMS. While 80% of menstruating women have experienced at least one symptom that could be attributed to PMS, estimates of prevalence range from as low as 3% to as high as 30%.

Mood symptoms such as emotional lability are both more consistent and more disabling than somatic symptoms such as bloating. A woman who experiences mood symptoms is likely to experience these symptoms consistently and predictably, whereas physical symptoms may come and go. Most women find that physical symptoms related to PMS are less disruptive than emotional symptoms.

History

PMS was originally seen as an imagined disease. When women first started reporting these symptoms, they were often told it was "all in their head". Interest in PMS began to increase after it was used as a criminal defense in Britain during the early 1980s.

The study of PMS was brought about by many characters in society. Physicians and researchers study and treat recognized medical conditions. In order to have an impact, the existence, and importance of a disease needs to be socially accepted. Women have contributed to the rise of interest in PMS and society's acceptance of it as an illness. It is argued that women are partially responsible for the medicalization of PMS. By legitimizing this disorder, women have contributed to the social construction of PMS as an illness. It has also been suggested that the public debate over PMS and PMDD was impacted by organizations who had a stake in the outcome including feminists, the APA, physicians and scientists.

The study of PMS symptoms is not a new development. Debates about the definition and validity of this syndrome have a long history. As stated above, growing public attention was given to PMS starting in the 1980’s. Up until this point, there was little research done surrounding PMS and it was not seen as a social problem. Through clinical trials and the work of feminists, viewing PMS in a social context had begun to take place.

Alternative views

Some medical professionals suggest that PMS might be a socially constructed disorder.

Supporters of PMS' medical validity claim support from the non-disputed status of a more serious but similar problem, Premenstrual dysphoric disorder ("PMDD"). In women with PMDD, studies have shown a correlation between self-reported emotional distress and levels of a serotonin precursor as measured by Positron emission tomography (PET). PMDD also has a consistent treatment record with SSRIs, when compared with placebos.

However, most supporters of PMS as a social construct do not dispute PMDD's medical status. Rather, they believe PMDD and PMS to be unrelated issues: one a product of brain chemistry, the other a product of a hypochondriatic culture. There has not been enough debate between the two views to come to any sound conclusion. Part of the reason the validity of the emotional aspects of PMS is being doubted is the lack of scientifically-sound studies on the matter. Many Western studies on PMS (PMS is primarily seen in Western Europe and North America) rely solely on self-reporting, and since Western women are socially conditioned to expect PMS or to at least know of its purported existence, they report their symptoms accordingly.

Another view holds that PMS is too frequently or wrongly diagnosed in many cases. A variety of problems, such as chronic depression, infections, and outbursts of frustration can be mis-diagnosed as PMS if they happen to coincide with the premenstrual period. Often, says this theory, PMS is used as an explanation for outbursts of rage or sadness, even when it is not the primary cause.

Some feminists have suggested that viewing PMS as a disease is born out of a patriarchal society. They assert that the symptoms that are associated with PMS are often in conflict with the way a woman "should" behave, contending that anger, irritability and increased sex drive are patterns of behavior which go against social norms for woman. Some people believe that PMS, along with other female-attributed disorders, are used to enforce gender stereotypes.

Some feminists assert that the emergence of PMS as a disorder occurred during a time when women's roles in society were changing. Particularly, women were beginning to enter the work force at increasing numbers. They argue that this may not be mere coincidence, asserting a belief that PMS is used as a method of social control.

The use of multiple SSRI's to treat PMS has caused some controversy. The makers of Prozac began marketing the generic form, fluoxetine, under the name Sarafem to treat PMS. This coincided with their loss of patent on Prozac, which has led to suggestions that their motivations are not completely benign. Recently an oral contraceptive named Yaz has become the first and only birth control pill approved to treat PMDD. The marketing of Yaz centers on this aspect of the drug.

Critics have also charged that the belief in PMS and its effects is mainly a Western creation. They assert that the diagnosis and definition of PMS and PMDD are not universal across the world, contending that in some non-Western countries societies this part of a women’s life is not seen in a negative way. They contend that while non-Westerners generally agree that women can be affected by their menstrual cycle, the defining PMS in terms of a disease is specific to the West in general and the United States in particular. Official recognition of PMDD has only taken place in the U.S. The Food and Drug Administration (FDA) accepts PMDD as an illness but the World Health Organization (WHO) does not. In Europe, PMDD was forcibly taken off the list of indications for Prozac due to lack of supporting evidence for its effectiveness. Some feminist scholars have argued that the Western or American view of the symptoms of these two disorders as negative in the U.S. and in need of treatment has allowed unwarranted involvement and regulation of women’s lives by the medical establishment.