Premenstrual emotional and physical changes occur in nearly 80% of menstruating women.
PMS symptoms vary from woman to woman and from cycle to cycle. Their intensity ranges from mild to incapaciting. About 20% to 40% of women who have PMS experience symptoms that make life difficult and 2.5% to 5% experience PMS that is debilitating.
It is not clear what causes premenstrual syndrome. A combination of physiological, genetic, nutritional, and behavioral factors are likely involved. There is no diagnostic test for PMS. Tests may be used rule out other conditions in women who experience severe symptoms. Emotional and physical changes that are in sync with a woman’s menstrual cycle are usually a telltale sign.
The most important indication of PMS is the cyclic nature of symptoms. There is usually a symptom free time period 1 week after menstruation ends. At least 25% of patients do not have a symptom free time period; therefore, they should be evaluated for other medical or psychiatric conditions.
Some women experience migraine headaches just prior to or during menstruation. These headaches, which are called menstrual migraines, may be related to hormonal changes and often do not occur during pregnancy.
PMS can be treated in a variety of ways. The initial and usually most effective treatment involves nonmedical changes in diet and lifestyle.
Scientists have been unable to identify a single cause of PMS. Theories range from hormonal and chemical to nutritional and psychological. Women whose mother or sisters have PMS are more likely to have it, so there may be a genetic component. A combination of genetic, physiological, and environmental causes are likely.
Hormones and neurochemicals
The physical, emotional, and psychological changes that occur in PMS coincide with hormonal changes of the menstrual cycle. PMS may be a response to declining levels of estrogen and progesterone that occur just prior to menstruation. The exact role of the various hormones are not clear. Some neurochemicals (chemicals that help make up the nervous system) also have been implicated. Hormones and neurochemicals may interact to produce PMS.
Mineralocorticoids are a group of hormones that regulate the bodyÂ’s fluids and electrolytes (e.g., sodium, potassium). Changing levels of mineralocorticoids may cause the bloated feeling that is common in women with PMS.
Prolactin stimulates breast development and the formation of milk during pregnancy and is associated with amenorrhea (abnormal absence of menstruation) and other gynecologic complications. Excess prolactin may cause the breast tenderness associated with PMS, although studies show that suppressing the secretion of excess prolactin does not relieve symptom.
Prostaglandins are hormonelike substances that play a role in the luteal phase of the menstrual cycle, which occurs prior to bleeding. Changing levels of prostaglandins may be involved in PMS.
Serotonin and gamma-aminobutyric acid (GABA) are chemicals that relay signals from one nerve cell to the next (neurotransmitters). Low levels of serotonin have been linked to depression, and low levels of GABA are associated with anxiety, both symptoms of PMS.
Endorphins are neurochemicals that suppress pain and increase the threshold to painful stimuli. Low levels of endorphins may be involved in PMS.
Nutrition probably plays a causal role in PMS. Women can alleviate many symptoms by changing their diet. Eliminating certain foods or drinks often reduces symptoms to more tolerable levels.
Hypoglycemia (low blood sugar) afflicts many PMS sufferers. Some researchers speculate that the hypoglycemia is a precursor to PMS.
Because depression-related symptoms are prevalent in women who suffer PMS, there may be an underlying psychological condition that causes or contributes to PMS. Approximately 60% of women with major affective disorder (e.g., depression) also have PMS, and more than 30% of women who suffer chronic depression experience their first depressive episode during a time of significant hormonal change (e.g., premenstrually). In one study, between 57% and 100% of women who suffered PMS were found to have had at least one prior major depressive episode, compared to 0% to 20% of women without PMS.
However, PMS encompasses more than depression, and by focusing too much on this aspect, other important physiological factors may be overlooked.
Signs and Symptoms
PMS has been characterized by more than 150 symptoms, ranging from mood swings to weight gain to acne. The symptoms vary from woman to woman and cycle to cycle. For some women, the symptoms may be mild or moderate, and for others, they may be so severe as to be incapacitating. Common symptoms include the following:
* Mood-related (“affective”) symptoms: depression, sadness, anxiety, anger, irritability, frequent and severe mood swings
* Mental process (“cognitive”) symptoms: decreased concentration, indecision
* Pain: headache (e.g., menstrual migraine), breast tenderness, joint and muscle pain
* Nervous system symptoms: insomnia (sleeplessness), hypersomnia (sleeping for abnormally long periods of time), anorexia (loss of appetite), food cravings, fatigue, lethargy, agitation, a change in sex drive, clumsiness, dizziness or vertigo, paresthesia (prickling or tingling sensation)
* Gastrointestinal symptoms: nausea, diarrhea
* Fluid and electrolyte symptoms: bloating, weight gain, oliguria (reduced urination)
* Palpitations (rapid fluttering of the heart), sweating
* Skin symptoms: acne, oily skin, greasy or dry hair
PMS is difficult to diagnose because there is not a clear cause and the symptoms are varied and are found in other disorders. The cyclical pattern is crucial for a diagnosis: symptoms appear prior to menstruation and resolve when bleeding begins.
The medical history and physical examination involve an evaluation of the symptoms and when they occur in relation to menstruation. Many health care providers advise women to keep a diary of menstrual cycles and the physical and psychological changes they experience over the course of several months. The menstrual diary provides clues to the physician and helps women understand and cope with the changes.
Thyroid function tests and other tests that evaluate the production of hormones are used to rule out other medical disorders.
Tests may be done to rule out dysmenorrhea (menstrual-related pain that occurs just before and during menstruation) and endometriosis.
Because depression is a common feature of PMS, some women undergo psychological counseling as part of the diagnostic procedure. Psychologists, who are professionally trained to recognize depression and other mood disorders, may be able to differentiate the cyclical pattern of depression associated with PMS from the psychiatric disorder.
Treatment of PMS focuses on relieving symptoms and involves exercise, dietary changes, and medication.
Exercise has a profound effect on hormones, including those involved in the menstrual cycle. Women who exercise experience less anger and depression. Exercise also reduces stress, which worsens PMS symptoms. Women, especially those who experience PMS, are encouraged to exercise regularly, 20-45 minutes, 3 times a week.
It is not clear how dietary changes affect PMS. Some studies show that drinking tea and increasing carbohydrates during the weeks preceding menstruation is helpful. Carbohydrates increase the level of the neurotransmitter serotonin (the low level of serotonin has been linked to PMS-related depression). Some nutritionists recommend vitamins, especially vitamin B6. Reducing or eliminating alcohol, caffeine, refined sugar, salt, dairy products, and animal fats may also be beneficial. A professional nutritionist or dietician can advise women on dietary changes that may relieve symptoms.
Stress reduction can help reduce PMS symptoms. Physical trainers and physical therapists can help women incorporate exercise and movement into their lives. A counselor or therapist can provide advice on reducing stress as well.
When exercise, diet, and other lifestyle changes have not helped, medication may be effective.
* Alprazolam may alleviate depressive and anxiety symptoms in some patients. It is taken orally and can be addictive.
* Fluoxetine (Prozac) reduces PMS symptoms when taken (20 mg per day, orally) during the menstrual cycle. It is well tolerated.
* GnRH agonist improves symptoms in most patients. It increases the risk for osteoporosis and is used only for a short time.
* Spironalactone has mixed results. It is taken orally.