Menstrual cramps are pains in the lowest part of the abdomen (pelvis), a few days before, during, or after a menstrual period. The pain tends to be most intense about 24 hours after periods begin and to subside after 2 to 3 days. The pain is often crampy or a dull, constant ache, but it may be sharp or throbbing and may come and go. It sometimes extends to the lower back or legs.
Many women also have a headache, nausea (sometimes with vomiting), and constipation or diarrhea. They may need to urinate frequently.
Some women with painful periods also have symptoms of premenstrual syndrome (such as irritability, nervousness, depression, fatigue, and abdominal bloating). These symptoms may persist during part or all of the menstrual period.
Dysmenorrhea interferes with daily activities in 30% or more of women and may result in absence from school or work. Women with dysmenorrhea have an increased likelihood of having chronic pelvic pain or other chronic pain conditions.
Causes of Menstrual Cramps
Menstrual cramps may:
Have no identifiable cause (called primary dysmenorrhea)
Result from another disorder (called secondary dysmenorrhea)
Primary dysmenorrhea usually starts during adolescence and may become less severe with age and after pregnancy. It is more common than secondary dysmenorrhea.
Secondary dysmenorrhea usually starts during adulthood (unless it is caused by a birth defect of the reproductive system).
Common causes
Experts think that primary dysmenorrhea may be caused by release of substances called prostaglandins into the blood or tissues during menstruation. Prostaglandin levels are high in women with primary dysmenorrhea. Prostaglandins may cause the uterus to contract (as occurs during labor), reducing blood flow to the uterus. These contractions can cause pain and discomfort. Prostaglandins also make nerve endings in the uterus more sensitive to pain.
Anxiety may also contribute to the pain.
Risk factors for severe symptoms include the following:
Early age of first period
Long or heavy menstrual periods
Never having been pregnant
Age < 30
Depression, anxiety, or high levels of stress
Smoking or excess alcohol
A family history of dysmenorrhea
Symptoms tend to lessen with increasing age and after a first pregnancy.
Secondary dysmenorrhea is caused by abnormalities in the reproductive system. It is commonly caused by
Endometriosis: Tissue that normally occurs only in the lining of the uterus (endometrial tissue) appears outside the uterus. Endometriosis is the most common cause of secondary dysmenorrhea.
Adenomyosis: Endometrial tissue grows into the wall of the uterus, causing it to enlarge and swell during menstrual periods.
Fibroids: These noncancerous tumors are composed of muscle and fibrous tissue and grow in the uterus.
Cervical stenosis: The passageway through the cervix (from the vagina to the main body of the uterus) is narrow or completely closed.
Less common causes
There are many less common causes of secondary dysmenorrhea. They include
Cysts and tumors in the ovaries
Use of an intrauterine device (IUD)
Scar tissue in the uterus
Birth defects of the vagina, cervix, or uterus
IUDs that release copper are often associated with painful periods. Those that release a progestin (a synthetic form of the female hormone progesterone) usually do not cause painful periods.
In a few women, pain occurs because the passageway through the cervix (cervical canal) is narrow. A narrow cervical canal (cervical stenosis) may develop after a procedure, as when a precancerous condition (dysplasia) of the cervix is treated.
Evaluation of Menstrual Cramps
Doctors usually diagnose dysmenorrhea when a woman reports that she regularly has bothersome pain during menstrual periods. They then determine whether dysmenorrhea is primary or secondary.
Warning signs
In women with dysmenorrhea, certain symptoms are cause for concern:
Severe pain that began suddenly or is new
Constant pain
Fever
A pus-like discharge from the vagina
Sharp pain that worsens when the abdomen is touched gently or the person moves even slightly
When to see a doctor
Women with any warning sign should see a doctor as soon as possible (usually the same day).
If women without warning signs have more severe cramps than usual or have pain that lasts longer than usual, they should see a doctor within a few days.
Other women who have menstrual cramps should call their doctor. The doctor can decide how quickly they need to be seen based on their other symptoms, age, and medical history.
What the doctor does
Doctors or other health care professionals ask about the pain and the medical history, including the menstrual history. Clinicians then do a physical examination. What they find during the history and physical examination may suggest a cause of menstrual cramps and the tests that may need to be done (see table Some Causes and Features of Menstrual Cramps).
For a complete menstrual history, clinicians ask women to describe their periods:
Age when menstrual periods started
How many days they last
How heavy they are
How long the interval between periods is
Whether periods are regular
Whether spotting occurs between periods
When symptoms occur in relation to periods
Clinicians also ask women to describe the following:
Age when menstrual cramps began
Any other symptoms, including pelvic pain unrelated to periods
Severity of the pain, what relieves or worsens symptoms (including nonsteroidal anti-inflammatory drugs), and how symptoms interfere with her daily activities
Any pain during sexual activity or problems becoming pregnant (as may occur in endometriosis)
Doctors ask about other disorders and conditions that can cause cramps, including use of certain drugs (such as birth control pills) or an IUD. Doctors ask about any surgical procedures that increase the risk of pelvic pain, such as a procedure that destroys or removes the lining of the uterus (endometrial ablation).
A pelvic examination is done. Doctors check for abnormalities, including discharge, pelvic area tenderness or enlargement of the uterus, cervical polyps, and fibroids.
Doctors also gently feel the abdomen to check for areas of particular tenderness, which may indicate severe inflammation in the abdomen (peritonitis).
Some Causes and Features of Menstrual Cramps
Cause | Common Features* | Tests |
|---|---|---|
Adenomyosis (growth of tissue that normally lines the uterus—called endometrial tissue—into the wall of the uterus) | Heavy, painful periods, vaginal bleeding between periods, pain in the lowest part of the abdomen (pelvis), and a feeling of pressure on the bladder and rectum Sometimes pain during sexual intercourse | Ultrasound or MRI of the pelvis In women with abnormal vaginal bleeding, sometimes a biopsy to rule out other causes of bleeding |
Birth defects of the reproductive tract (rare) | Sometimes periods that never start (primary amenorrhea) Sometimes abnormalities found during the pelvic examination, such as a blockage in the vagina or a lump in the pelvis | Sometimes hysterosalpingography (x-rays taken after a contrast agent is injected into the uterus and fallopian tubes), sonohysterography (ultrasound after fluid is infused into the uterus), or MRI |
Cervical stenosis (narrowing of the passageway through the cervix) | Irregular or no menstrual periods, vaginal bleeding between periods, infertility, and abdominal pain that occurs in cycles | Sometimes ultrasound of the pelvis |
Cysts and tumors in the ovaries (ovarian cancer or noncancerous ovarian growths) | Often no other symptoms Sometimes abnormal vaginal bleeding Sometimes indigestion, bloating, changes in urination, pelvic pain, or backache | Ultrasound or other imaging tests If cancer is suspected, blood tests to measure substances produced by certain tumors |
Endometriosis (patches of endometrial tissue that are abnormally located outside the uterus) | Dull or crampy pain that occurs before and during the first days of menstrual periods Infertility Often pain during sexual intercourse, bowel movements, or urination | Ultrasound of the pelvis Sometimes laparoscopy (insertion of a viewing tube through a small incision just below the navel) |
Often no other symptoms With large fibroids, sometimes pain, pressure, or heavy vaginal bleeding | Ultrasound Sometimes sonohysterography or hysteroscopy (use of a thin viewing tube to see the interior of the uterus) If results are unclear, MRI | |
Intrauterine devices (IUDs) that release copper or, less often, those that release a progestin (a synthetic form of the female hormone progesterone) | Heavy menstrual bleeding | Sometimes ultrasound of the pelvis to determine whether the IUD is correctly placed in the uterus |
Pelvic venous disorders (chronic pain due to accumulation of blood in veins of the pelvis) | Pain that is
Often low back pain, aches in the legs, and abnormal vaginal bleeding Occasionally a clear or watery discharge from the vagina Sometimes fatigue, mood swings, headaches, and bloating | Ultrasound or specialized imaging techniques Sometimes laparoscopy |
* Features include symptoms and results of the clinician's examination. Features mentioned are typical but not always present. | ||
MRI = magnetic resonance imaging. | ||
Testing
Testing is done to rule out disorders that may be causing the pain. For most women, tests include
A pregnancy test in all women of reproductive age
Ultrasound of the pelvis to check for fibroids, polyps, endometriosis, adenomyosis, and cysts or masses in the ovaries
If pelvic inflammatory disease is suspected, a sample of secretions is taken from the cervix, examined under a microscope, and sent to a laboratory to be tested.
If results of these tests are unclear and symptoms persist, one or more of the following tests is done:
Imaging tests such as hysterosalpingography or sonohysterography to identify polyps, fibroids, and birth defects
Hysteroscopy to identify problems with the cervix or uterus (but not with the ovaries)
Magnetic resonance imaging (MRI) to identify other abnormalities
Laparoscopy if results of other tests are unclear
For hysterosalpingography, x-rays are taken after a substance that can be seen on x-rays (radiopaque contrast agent) is injected through the cervix into the uterus and fallopian tubes. If results are unclear, magnetic resonance imaging (MRI) may be done.
For sonohysterography, ultrasound is done after fluid is infused in the uterus through a thin tube inserted through the vagina and cervix. The fluid makes abnormalities easier to identity.
For hysteroscopy, doctors insert a thin viewing tube through the vagina and cervix to view the interior of the uterus. This procedure can be done in a doctor's office or in a hospital as an outpatient procedure.
For laparoscopy, a viewing tube is inserted through a small incision just below the navel and is used to view the uterus, fallopian tubes, ovaries, and organs in the abdomen. This procedure is done in a hospital or surgical center. Laparoscopy enables doctors to directly view structures in the pelvis.
Treatment of Menstrual Cramps
Nonsteroidal anti-inflammatory drugs (NSAIDs)
Often hormonal contraceptives
Treatment of underlying disorders
When menstrual cramps result from another disorder, that disorder is treated if possible. For example, a narrow cervical canal can be widened surgically. However, this operation usually relieves the pain only temporarily. If needed, fibroids or misplaced endometrial tissue (due to endometriosis) is surgically removed.
If women have primary dysmenorrhea do not have a specific disorder that can be treated, they may use general measures or NSAIDs to relieve symptoms.
General measures
Moist heat applied to the abdomen or abdominal massage may help.
Getting enough sleep and rest and exercising regularly may also help.
Other measures that have been suggested to help relieve the pain include a low-fat diet and nutritional supplements such as omega-3 fatty acids, flaxseed, magnesium, vitamin B1, vitamin E, and zinc. There is not much evidence to support the usefulness of diet or these nutritional supplements, but most have few risks and so some women may try them. Women should talk to their doctors before using these supplements.Other measures that have been suggested to help relieve the pain include a low-fat diet and nutritional supplements such as omega-3 fatty acids, flaxseed, magnesium, vitamin B1, vitamin E, and zinc. There is not much evidence to support the usefulness of diet or these nutritional supplements, but most have few risks and so some women may try them. Women should talk to their doctors before using these supplements.
Medications
If pain is bothersome, NSAIDs, such as ibuprofen, naproxen, or mefenamic acid, may help. NSAIDs should be started 24 to 48 hours before a period begins and continued 1 or 2 days after the period begins.If pain is bothersome, NSAIDs, such as ibuprofen, naproxen, or mefenamic acid, may help. NSAIDs should be started 24 to 48 hours before a period begins and continued 1 or 2 days after the period begins.
If NSAIDs are ineffective, doctors may recommend also taking birth control pills that contain a progestin (a synthetic form of the female hormone progesterone) and estrogen. These pills prevent the ovaries from releasing an egg (ovulation). Women who cannot take estrogen can take birth control pills that contain only a progestin.
Other hormone treatments may be used if NSAIDs or birth control pills do not relieve symptoms. They include progestins (such as levonorgestrel, etonogestrel, medroxyprogesterone, or micronized progesterone, taken by mouth), Other hormone treatments may be used if NSAIDs or birth control pills do not relieve symptoms. They include progestins (such as levonorgestrel, etonogestrel, medroxyprogesterone, or micronized progesterone, taken by mouth),gonadotropin-releasing hormone (GnRH) agonists (such as leuprolide and nafarelin), GnRH antagonists (such as elagolix), an IUD that releases a progestin, or danazol (a synthetic male hormone). GnRH agonists and antagonists help relieve menstrual cramps due to endometriosis. Danazol is not frequently used because it has many side effects.(such as leuprolide and nafarelin), GnRH antagonists (such as elagolix), an IUD that releases a progestin, or danazol (a synthetic male hormone). GnRH agonists and antagonists help relieve menstrual cramps due to endometriosis. Danazol is not frequently used because it has many side effects.
Other treatments
Surgical procedures are options to treat gynecologic causes of secondary dysmenorrhea. If a woman may have endometriosis and medications have not worked or if she has infertility, doctors may do laparoscopic surgery to confirm the diagnosis of endometriosis and remove endometrial tissue (tissue from the lining of the uterus) that is located outside the uterus. Uterine leiomyomas or cervical stenosis may also be treated surgically. Surgery to remove the uterus (hysterectomy) ends dysmenorrhea.
If women have severe pain that persists despite all other types treatment, doctors may do a procedure that disrupts the nerves to the uterus and thus blocks pain signals. These procedures include the following:
Injecting the nerves with an anesthetic (a nerve block)
Destroying the nerves using a laser, electricity, or ultrasound
Cutting the nerves
The procedures to disrupt the nerves may be done using a laparoscope. When these nerves are cut, other organs in the pelvis, such as the ureters, are occasionally injured.
Lifestyle or complementary care approaches that have been evaluated include regular exercise, yoga, hypnosis, acupuncture, acupressure, chiropractic therapy, and heat therapy.
Use of dietary supplements (such as ginger, vitamin E) and cannabinoids have also been proposed as possible treatments for menstrual cramps, but require further study.(such as ginger, vitamin E) and cannabinoids have also been proposed as possible treatments for menstrual cramps, but require further study.
Key Points
Dysmenorrhea is pelvic cramps or pain during menses.
Usually, menstrual cramps have no identifiable cause (called primary dysmenorrhea).
Pain is often crampy or a dull, constant ache but may be or sharp or throbbing and usually starts a few days before a menstrual period, and subsides after 2 or 3 days.
For most women, evaluation includes a pregnancy test, a doctor's examination, and ultrasound (to check for abnormal structures or growths in the pelvis).
For primary dysmenorrhea, general measures, such as adequate sleep, regular exercise, and heat may help relieve symptoms.
NSAIDs or an NSAID plus birth control pills that contain a progestin and estrogen may help relieve the pain.
Drugs Mentioned In This Article
