Menstrual Cramps.(Dysmenorrhea; Painful Periods)
Menstrual cramps are
pains in the lowest part of the torso (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 usually crampy or
sharp and comes and goes, but it may be a dull, constant ache. It sometimes
extends to the lower back and legs.
Many women also have a
headache, nausea (sometimes with vomiting), and constipation or diarrhea. They
may need to urinate frequently.
Symptoms of premenstrual
syndrome (such as irritability, nervousness, depression, fatigue, and
abdominal bloating) may persist during part or all of the menstrual period.
Sometimes menstrual
blood contains clots. The clots, which may appear bright red or dark, may
contain tissue and fluid from the lining of the uterus, as well as blood.
Symptoms tend to be
more severe if
- Menstrual periods started at an early age.
- Periods are long or heavy.
- Women smoke.
- Family members also have dysmenorrhea.
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.
Common causes
More than 50% of women
with dysmenorrhea have
- Primary dysmenorrhea
In about 5 to 15% of
these women, cramps are severe enough to interfere with daily activities and
may result in absence from school or work.
Experts think that
primary dysmenorrhea may be caused by release of substances called
prostaglandins 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.
Lack of exercise and
anxiety about menstrual periods may also contribute to the pain.
Secondary
dysmenorrhea 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.
- Fibroids: These noncancerous tumors are
composed of muscle and fibrous tissue and grow in the uterus.
- Adenomyosis: Endometrial tissue grows into the
wall of the uterus, causing it to enlarge and swell during menstrual
periods.
Less common causes
There are many less common causes of secondary dysmenorrhea. They include
- Birth defects
- Cysts and tumors in the ovaries
- Use of an intrauterine device (IUD) that releases copper or a progestin (a synthetic form of the female hormone progesterone)
IUDS that release a
progestin cause less cramping than those that release copper.
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 polyp in the uterus is removed or a precancerous condition (dysplasia)
or cancer of the cervix is treated. A growth (polyp or fibrosis) can also
narrow the cervical canal.
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.
Doctors must check for
two serious disorders that can also cause pelvic pain:
- An abnormally located pregnancy ( ectopic
pregnancy)—that is, one not in its usual location in the uterus
- Pelvic inflammatory disease―infection of
the uterus and/or fallopian tubes and sometimes the ovaries
Doctors can usually
identify these disorders because the pain and the other symptoms they cause typically
differ from those of dysmenorrhea.
An ectopic
pregnancy usually causes sudden pain that begins in a specific spot
and is constant (not crampy). It may or may not be accompanied by vaginal
bleeding. The pain may become severe. If the ectopic pregnancy ruptures, women
may feel light-headed, faint, have a racing heart, or go into shock.
In pelvicinflammatory disease, the pain may become severe and may be felt on
one or both sides. Women may also have a foul-smelling, puslike discharge from
the vagina, vaginal bleeding, or both. Sometimes women have a fever, nausea or
vomiting, or pain during sexual intercourse or urination.
Warning signs
In women with
dysmenorrhea, certain symptoms are cause for concern:
- Severe pain that began suddenly or is new
- Constant pain
- Fever
- A puslike 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 that 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 practitioners ask about the pain and the medical history, including
the menstrual history. Practitioners 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, practitioners ask the woman
- How old she was when menstrual periods started
- How long they last
- How heavy they are
- How long the interval between periods is
- Whether periods are regular
- Whether spotting occurs between periods or after sex
- When symptoms occur in relation to periods
Practitioners also ask
the woman the following:
- How old she was when symptoms began
- What other symptoms she has
- What the pain is like, including how severe it is, what relieves or worsens symptoms, and how symptoms interfere with her daily activities
- Whether she has pelvic pain unrelated to periods
- Whether acetaminophen or nonsteroidal anti-inflammatory drugs (NSAIDs) help relieve the pain
The woman is asked
whether she has or has had disorders and other conditions that can cause
cramps, including use of certain drugs (such as birth control pills) or an IUD.
She is also asked about physically or emotionally traumatic experiences, such
as sexual abuse. Practitioners ask whether she has had 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 the vagina, vulva, cervix, uterus, and
the area around the ovaries for abnormalities, including polyps and fibroids.
Doctors also gently
feel (palpate) the abdomen to check for areas of particular tenderness, which
may indicate severe inflammation in the abdomen ( peritonitis).
Testing
Testing is done to
rule out disorders that may be causing the pain. For most women, tests include
- A pregnancy test
- Ultrasonography of the pelvis to check for
fibroids, endometriosis, adenomyosis, and cysts in the ovaries
If pelvic inflammatorydisease is suspected, a sample of secretions is taken from the cervix, examined
under a microscope, and sent to a laboratory to be tested.
If these tests are
inconclusive and symptoms persist, one or more of the following tests is
done:
- Hysterosalpingography or sonohysterography to identify polyps, fibroids, and birth defects
- Magnetic resonance imaging (MRI) to identify other abnormalities or, if surgery is planned, to provide more information about previously identified abnormalities
- Hysteroscopy to identify problems with the cervix or uterus (but not with the ovaries)
- Laparoscopy if needed
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.
For sonohysterography, ultrasonography
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.
If results of
hysterosalpingography or sonohysterography are inconclusive, hysteroscopy or
laparoscopy can be done. Both hysteroscopy and laparoscopy enable doctors to
directly view structures in the pelvis. Laparoscopy enables doctors to examine
all of the pelvis and reproductive organs.
Treatment of Menstrual Cramps
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.
When doctors diagnose
primary dysmenorrhea, they reassure women that no other disorder is causing the
pain and recommend general measures to relieve symptoms.
General measures
The first step toward
relieving symptoms is getting enough sleep and rest and exercising regularly.
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. Moist heat applied to the abdomen may also
help.
Drugs
If pain persists,
nonsteroidal anti-inflammatory drugs (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 and a low dose of 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 also help relieve symptoms. They include danazol (a
synthetic male hormone), 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), and an IUD that releases a
progestin. GnRH agonists and antagonists help relieve menstrual cramps due to
endometriosis.
Drugs such as gabapentin may
also help relieve symptoms. Gabapentin is an antiseizure drug
that is sometimes used to reduce pain due to nerve damage.
Other treatments
If women have severe
pain that persists despite 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.
Some alternative
treatments for menstrual cramps have been suggested but have not been studied
well. They include behavioral counseling (such as systematic desensitization
and relaxation and pain management training), acupuncture,
acupressure, chiropractic therapy, and transcutaneous electrical
nerve stimulation (application of a gentle electric current through
electrodes placed on the skin). Hypnosis is being studied as treatment.
Key Points about
Menstrual Cramps
- Usually, menstrual cramps have no identifiable cause (called primary dysmenorrhea).
- Pain is typically crampy or sharp, 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 ultrasonography (to check for abnormal structures or growths in the pelvis).
- For primary dysmenorrhea, general measures, such as adequate sleep, regular exercise, heat, and a low-fat diet, may help relieve symptoms.
- NSAIDs or an NSAID plus low-dose birth control pills may help relieve the pain.