This study will examine pelvic pain associated with endometriosis and explore better
approaches to treatment. In women with endometriosis, uterine tissue grows outside the
uterus. Standard treatments - altering hormone levels to prevent endometrial tissue growth or
surgically removing endometrial tissue - treat pelvic pain only temporarily. This study will
investigate the role of sex hormones, immune chemicals, stress hormones, and genes in pelvic
pain and determine how the nerve, muscle, and skeletal systems are involved in this pain.
Women between 18 and 50 years of age who:
1. have endometriosis and chronic pelvic pain, and
2. have chronic pelvic pain without endometriosis, and
3. have neither endometriosis nor chronic pelvic pain and are willing to have a tubal
ligation (Healthy Volunteer group),
may be eligible for this study. Candidates are screened with a questionnaire to obtain
information about their pain and previous treatments and related medical or social issues.
Participants will undergo the following tests and procedures:
1. Medical history and physical examination, including pelvic exam, blood tests,
urinalysis, and diaphragm fitting.
2. Questionnaires about pain, quality of life, sexuality, psychological attitudes,
spiritual experiences, and history of headache and depression.
3. At-home monitoring for 4 to 6 weeks of pain symptoms, menstruation and spotting,
medicines taken, and urine collections to test for "LH" surge. LH is the hormone that
causes the ovary to release a mature egg.
4. Pre-laparoscopy evaluation to include:
- Examination of menstrual blood collected in a diaphragm for 4 hours.
- Blood sampling to measure adrenal and pituitary hormones. For this test,
corticotrophin-releasing hormone (CRH) is injected through an IV needle. Up to five
blood samples are drawn, starting before the injection until 45 minutes after it.
Blood is also collected at this time for genetic analysis.
- In-depth pain assessment to identify trigger points in muscles associated with
pelvic pain, regions of skin sensitivity, and bone pain. Some women will undergo
microdialysis, which uses an acupuncture-type needle to collect chemicals from two
- Blood sampling twice a week for 1 month to measure changes in blood substances
during the menstrual cycle.
- Blood sampling after the LH surge to measure progesterone levels.
- Cervicovaginal lavage (washing of the cervix with saline and collecting the fluid)
to obtain secretions for research.
- Ultrasound of the ovaries and uterus. This examination uses a probe inserted into
the vagina that emits sound waves that are used to form pictures of the internal
structures. A small piece of uterine lining is also obtained for examination and
- A visit with the members of the Pain and Palliative care service to evaluate the
pain in anticipation of offering other treatments for pain after surgery.
CPP + Endo or CPP only: Laparoscopy to look for and remove endometrial tissue. This procedure
is done under general anesthetic. A viewing instrument called a laparoscope is passed through
an incision in the belly button to look for endometriosis. If it is found, two or more
incisions are made in the abdomen for other instruments to remove the tissue. A small piece
of uterine lining is also obtained for examination and research purposes.
Healthy Volunteers: Laparoscopy to perform the tubal ligation. A tubal ligation, commonly
known as "getting your tubes tied," is a surgical procedure for women to sterilize them. This
procedure closes the fallopian tubes, stopping the egg from traveling from the ovary to the
uterus and preventing sperm from reaching the fallopian tube to fertilize an egg. In a tubal
ligation, fallopian tubes are cut, burned, or blocked with rings, bands or clips. The surgery
is effective immediately. Tubal ligations are 99.5% effective as birth control. This
procedure is done under general anesthetic. A viewing instrument called a laparoscope is
passed through an incision in the belly button to perform a tubal ligation. Two or more
incisions are made in the abdomen for other instruments to perform the procedure. During the
laparoscopy, we will look for and remove endometrial tissue. A small piece of uterine lining
is also obtained for examination and research purposes.
-Follow-up evaluations. Two weeks after surgery, patients return to NIH to discuss the
surgical findings and treatment options. Follow-up visits are then scheduled at 1, 3, and 6
months after surgery to complete questionnaires and determine if the treatment is working.
Blood samples are drawn at each visit.
Chronic pelvic pain associated with endometriosis is poorly understood. This study is an
effort to better understand pelvic pain and identify novel medical approaches for treating
it. Endometriosis is a very common disease of women in their reproductive years, in which
endometrial tissue grows outside the uterus. In a recent epidemiologic study, we have shown
strong associations among endometriosis, fibromyalgia, and autoimmune disorders. Currently,
it is believed that endometriosis causes chronic pelvic pain. Yet, some women with
endometriosis do not have any pain and others have pain in areas unrelated to endometriosis
disease location. The standard approaches to treating endometriosis pain have been to
medically alter hormone levels to prevent endometriosis tissue growth or to surgically remove
endometriosis lesions. Pelvic pain is only temporarily treated by either approach, which
suggests that the current classification of pain, based on disease and treatment with
hormones or surgery is not adequate. The feeling of pain involves many complex processes.
Generally, women suffer more frequently from chronic, long-term, painful conditions than men.
This suggests that women process pain differently because of differences in sex hormone
levels and genes expressed in a sexually dimorphic fashion, as well as in central nervous and
immune system function differences. We will examine the relations among sex hormones, pain
processing, immune system substances and pain related genes. We will also examine changes in
levels of hormonal and immune substances in the blood, endometriosis lesions and normal
endometrial tissue. Myofascial pain has been noted in women with endometriosis and chronic
pelvic pain. We will study how the nerve, muscle and skeletal systems are involved in pelvic
pain by performing an in depth pain assessment. Finally, stress plays an important role
generating and perpetuating chronic pain. We will examine how the hormones related to the
stress response may be altered in pelvic pain.
- INCLUSION CRITERIA:
Women between the ages of 18 and 50 years, who have their reproductive organs. Those
undergoing tubal ligation must be at least 21 years old.
Excellent health other than a three-month history of pelvic pain and documented
endometriosis at laparoscopy. Chronic medications may be acceptable at the discretion of
the Principal Investigator (PI). Use of antidepressants, medications for migraines and
headaches, allergy medications, and treatment of bowel symptoms such as irritable bowel
disease will be allowed.
Do not desire pregnancy for the duration of the study.
Are using abstinence, mechanical (condoms, diaphragms) or sterilization methods of
contraception and are willing to continue using them throughout the study.
Willing and able to give informed consent.
Willing and able to comply with study requirements.
BMI less than 32 kg/m(2).
History of regular cyclic menses.
Women with other causes of chronic pelvic pain including infectious, gastrointestinal,
psychologic disorders, fibromyalgia and chronic fatigue syndrome.
Significant abnormalities in the physical or laboratory examination including renal and
liver function more than twice the normal range.
Hysterectomy or bilateral salpingo-oophorectomy.
Use of hormonal contraception, selective estrogen receptor modulators, progestins,
estrogens, steroids, or ovulation induction in the last 3 months.
Other medical or surgical treatment for endometriosis in the last 6 months.
Untreated abnormal pap smear or other gynecologic condition.
Manic-depressive illness or untreated major depression.