Endometriosis
What is it?
Overview
What Is It?
Endometriosis is a condition in which tissue similar to your uterine lining grows outside your uterus and gets stuck to other organs or structures, often resulting in pain or infertility.Endometriosis is a non-cancerous condition in which tissue similar to the endometrium (uterine lining) grows outside your uterus and adhere to other pelvic structures, most commonly the ovaries, bowel, fallopian tubes or bladder. It is a common cause of pelvic pain and infertility. It affects at least 5 percent of premenopausal women, and at least 5.5 million women in North America alone have endometriosis.
Historically thought of as a disease that affects adult women, endometriosis is increasingly being diagnosed in adolescents, as well.
Symptoms of Endometriosis
The type and intensity of symptoms range from completely disabling to mild. Sometimes, there aren't any symptoms at all, particularly in women with so-called "unexplained infertility." The most common symptoms are painful menstrual periods and/or pelvic pain. Others include:
- Diarrhea and painful bowel movements, especially during menstruation
- Intestinal pain
- Painful intercourse
- Abdominal tenderness
- Backache
- Severe menstrual cramps
- Excessive menstrual bleeding
- Pain in the pelvic region with exercise
- Painful pelvic examinations
- Infertility
Characteristics of Endometriosis
Endometrial tissue also may grow in the abdominal area or, more rarely, travel far from the pelvic region into the lungs, skin and other regions of the body. No matter where it goes, however, endometrial tissue continues to respond to hormonal signals—specifically estrogen—from the ovaries each month telling it to grow.
Estrogen is the hormone that causes your uterine lining to thicken each month. When estrogen levels drop, the lining is expelled from the uterus, resulting in menstrual flow (you get your period). But unlike the tissue lining the uterus, which leaves your body during menstruation, endometriosis tissue is trapped in the pelvic cavity. With no place to go, the tissue bleeds internally. Your body reacts to the internal bleeding with inflammation, a process that can lead to the formation of scar tissue, also called adhesions. This inflammation and the resulting scar tissue may cause pain and other symptoms.
Recent research also finds that this misplaced endometrial tissue may develop its own nerve supply to communicate with the brain, one reason for the condition's severe pain and the other chronic pain conditions so many women with endometriosis suffer from.
Risks of Endometriosis
If your endometriosis results in scarring of the reproductive organs, it may affect your ability to get pregnant. In fact, 35 to 50 percent of women with endometriosis have difficulty getting pregnant. Even mild endometriosis can result in infertility.
Causes of Endometriosis
Researchers don't know what causes endometriosis, but many theories exist.
- Retrograde Menstruation: One suggests that retrograde menstruation—or "reverse menstruation"—may be the main cause. In this condition, menstrual blood doesn't flow out of the cervix (the opening of the uterus to the vagina), but, instead, is pushed backward out of the uterus through the fallopian tubes into the pelvic cavity.But because most women experience some amount of retrograde menstruation without developing endometriosis, researchers believe something else may contribute to its development. For example, endometriosis could be an immune system problem or hormonal imbalance that enables the endometrial tissue to take root and grow after it is pushed out of the uterus.
- Reproductive Cell Growth: Other researchers believe that in some women, certain abdominal cells mistakenly turn into endometrial cells. These same cells are the ones responsible for the growth of a woman's reproductive organs in the embryonic stage. It's believed that something in the woman's genetic makeup or something she's exposed to in the environment in later life changes those cells so they turn into endometrial tissue outside the uterus. There's also some thinking that damage to cells that line the pelvis from a previous infection can lead to endometriosis.
- Environmental Factors: Some studies show that environmental factors may play a role in the development of endometriosis. Toxins in the environment such as dioxin seem to affect reproductive hormones and immune system responses, but this theory has not been proven and is controversial in the medical community.
- Structural Factors: Other researchers believe the endometrium itself is abnormal, which allows the tissue to break away and attach elsewhere in the body.
- Genetics: Endometriosis may have a genetic link, with studies finding a 5 to 7 percent increase in risk if your mother or sister had the disorder. No specific genetic mutation has been clearly linked with the disease. Research also indicates that daughters of women who took the drug diethylstilbestrol (DES) between 1938 and 1971 to prevent miscarriage have an increased risk of endometriosis.
Diagnosis
Diagnosis
Gynecologists and reproductive endocrinologists, gynecologists who specialize in infertility and hormonal conditions, have the most experience in evaluating and treating endometriosis.
The condition can be very difficult to diagnose, however, because symptoms vary so widely and may be caused by other conditions.
Among the ways doctors diagnosis the disease are:
Laparoscopy. At present, laparoscopy is still the gold standard for the diagnosis of endometriosis and is commonly used for both diagnosis and treatment. Performed under general anesthesia, the surgeon inserts a miniature telescope called a laparoscope through a small incision in the navel to view the location, size and extent of abnormalities (such as adhesions) in the pelvic region.
However, merely looking through the laparoscope can't diagnose deep endometriosis disease, in which the endometrial tissue is hidden inside adhesions or underneath the lining of the abdominal cavity. More extensive dissection is needed to diagnose and treat this type of disease.
Many women have a combination of both deep and superficial (in which the endometrial tissue can be easily seen) endometrial disease.
Peritoneal tissue biopsy. During the laparoscopy, the doctor may remove a tiny piece of peritoneal tissue (the inner layer of the lining of the abdominal cavity) or other suspicious areas to help establish the diagnosis of endometriosis. This is recommended by the American College of Obstetricians and Gynecologists (ACOG), which notes that only an experienced surgeon familiar with the appearance of endometriosis should rely on visual inspection alone to make the diagnosis. A biopsy, however, is not mandatory to diagnose endometriosis, and a negative biopsy does not rule out the presence of this disease in other areas within the abdomen.
Ultrasonography, MRI and CT scan. An ultrasound uses sound waves to visualize the inside of your pelvic region, while an MRI uses magnets and a CT scan uses radiation. While these tests can suggest endometriosis or rule out other conditions, none can definitively confirm the condition.
At this point, there is no noninvasive method to diagnosis endometriosis, which is frustrating for both women and their health care providers.
Pelvic exam. Your doctor may perform a physical examination, including a pelvic exam, to diagnose endometriosis. If all other causes of endometriosis can be ruled out, your doctor may treat the condition without any further exams.
Medical history. A detailed medical history may offer your health care professional the earliest clues in making the correct diagnosis. According to the Endometriosis Association, clues you may be at risk for endometriosis include painful bowel movements, frequent respiratory infections (a sign your immune system isn't working properly), allergies, chemical sensitivities, frequent yeast infections and severe menstrual cramps. A simple five-question test about these conditions can quickly determine if you are at risk.
Blood test. CA-125 is a blood test used to detect a certain protein commonly found in the blood of women with endometriosis. Although CA-125 commonly reveals an elevation in such blood protein in women with advanced endometriosis, it's not as sensitive to earlier stages of the disease and is often elevated in a host of other gynecologic conditions including uterine fibroids, abdominal or pelvic adhesions, prior infection and even ovarian cancer. Measurement of this blood level is not considered a standard part of the evaluation of a woman with suspected endometriosis.
Treatment
There is no cure for endometriosis. However, there are a number of options available for treating and managing the disease after diagnosis. They fall into four categories: medical, surgical, alternative treatments and pregnancy.
Medical. The most common medical therapies for endometriosis are nonsteroidal anti-inflammatories (NSAIDs), hormonal contraceptives (in oral, patch, or injectable applications) and other hormonal regimens, such as GnRH agonists (gonadotropin-releasing hormone drugs).
Non-steroidal anti-inflammatories (NSAIDs). These drugs, such as ibuprofen, naproxen and aspirin, are often the first step in controlling endometriosis-related symptoms. They may be used indefinitely to manage symptoms, in part because they are cheaper and easier to use than other options and have fewer side effects than hormonal treatments. However, some patients may experience severe gastrointestinal upset from these agents, particularly if they are administered for prolonged periods and at high doses. They are more effective when taken regularly. Other pain relievers may be prescribed if NSAIDs are not effective.
Contraceptive hormones (birth control pills). This option also costs less and has fewer side effects than other hormonal treatment options and may be recommended soon after diagnosis. Birth control pills stop ovulation, thus suppressing the effects of estrogen on endometrial tissue. Often physicians will recommend using birth control pills in a continuous as opposed to cyclic fashion to eliminate regular menstrual flow which can be the cause of increased pain in some women with endometriosis.
Medroxyprogesterone (Depo-Provera). This injectable drug, usually used as birth control, effectively halts menstruation and the growth of endometrial tissue, relieving the signs and symptoms of endometriosis. Side effects include weight gain, depressed mood and abnormal uterine bleeding (breakthrough bleeding and spotting), as well as a prolonged delay in returning to regular menstrual cycles, which can be of concern to women who want to conceive.
Gonadotropin Releasing Hormone Drugs (GnRH agonists). Leuprolide (Lupron), nafarelin (Synarel) and goserelin (Zoladex) are among the other hormonal treatments used to treat endometriosis. They temporarily relieve the condition by blocking the estrogen production that stimulates its growth.
However, they have side effects, including menopausal symptoms like hot flashes, vaginal dryness and reversible loss of bone density. Add-back hormone therapy, which typically consists of a synthetic progesterone (progestin) administered alone or in combination with a low-dose estrogen, is typically prescribed along with GnRH agonists to alleviate these side effects.
Danazol. This reproductive hormone is a synthetic form of a male hormone (androgen) and is available as Danocrine. It is also used to treat endometriosis and works by directly suppressing endometrial tissue and suppressing ovarian hormone production. A woman taking danazol will typically not ovulate or get regular periods. Side effects may include weight gain, hair growth and acne, among others. Some of the side effects are reversible. Danazol is typically given for six to nine months at a time. Danazol is not a contraceptive agent, and it is critical that any woman taking this drug also use a barrier contraceptive (condoms, diaphragm, IUD) if she is sexually active.
Progestin-containing intrauterine device. Recent studies have shown that an intrauterine device (IUD) containing a synthetic type of progesterone (progestin) and marketed as the Mirena Intrauterine System can also reduce the painful symptoms and extent of disease associated with endometriosis. If effective, this device can be left in the uterus for five years and can be removed if a woman wants to conceive. It should not be used in women with multiple sexual partners, those with an abnormal uterus (fibroids) or those with prior sexually transmitted disease. Side effects include cramping and breakthrough bleeding.
Experimental approaches. Many medications that show great promise are being evaluated in research trials. These include a variety of classes of drugs including GnRH antagonists, selective progesterone receptor modulators, immunomodulators and aromatase inhibitors. None of these medications are currently approved for standard use.
Surgical.
The goal of any surgical procedure should be to remove endometriotic tissue and scar tissue. Hormonal therapies may be prescribed together with the more conservative surgical procedures.
Surgical treatments range from removing the endometrial tissues via laparoscopy to removing the uterus, called a hysterectomy, often with the ovaries (called an oophorectomy). Surgery classified as "conservative" removes the endometrial growths, adhesions and scar tissue associated with endometriosis without removing any organs. Conservative surgery may be done with a laparoscope or, if necessary, through an abdominal incision.
Laparoscopy. During a laparoscopy, an outpatient surgery also referred to as "belly-button surgery," the surgeon views the inside of the abdomen through a tiny lighted telescope inserted through one or more small incisions in the abdomen. From there, the surgeon may destroy endometrial tissue with heat, laser or by cutting it out. There is a risk of scar tissue, which could lead to infertility, making pain worse, or damaging other pelvic structures. Surgery to remove endometriosis involving the ureters and bowel can be especially complex and requires a high degree of surgical skill.
Laparotomy. A laparotomy is similar to a laparoscopy but is more extensive, involving a full abdominal incision and a longer recovery period.
Hysterectomy. During a hysterectomy, your uterus is removed. This leaves you infertile. Hysterectomy alone may not eliminate all endometrial tissue, however, because it can't remove tissue outside of the uterus or ovaries. Additionally, surgery to remove the uterus may not relieve the pain associated with endometriosis.
Oophorectomy. Removing the ovaries with the uterus improves the likelihood of successful treatment with hysterectomy because the ovaries secrete estrogen, which can stimulate growth of endometriosis. It also renders you infertile, however.
If you wish to preserve your fertility, discuss other treatment options with your health care professional and consider seeking a second opinion.
There have been no comparative studies of medical and surgical therapies to see which approach is better. Each has advantages and disadvantages. Often, your plan of care will be a combination of treatments.
Alternative treatments.
Alternative treatments for relieving the painful symptoms of endometriosis include traditional Chinese medicine, nutritional approaches, exercise, yoga, homeopathy, acupuncture, allergy management and immune therapy.
While some health care professionals may tell you these alternative paths to seeking pain relief from endometriosis are a waste of time, others may encourage you to try alternative methods of pain relief as long as they are not harmful to your condition. Either way, discuss any options you want to try with your health care professional. Also keep in mind that while these options may help relieve the pain of endometriosis, they won't cure the condition.
Pregnancy. While it can't be considered a "treatment" for endometriosis, pregnancy may relieve endometriosis-related pain, an improvement that may continue after the pregnancy ends.
Health care professionals attribute this pregnancy-related relief to the hormonal changes of pregnancy. For example, ovulation and menstruation stops during pregnancy, and it's menstruation that triggers the pain of endometriosis.
Plus, endometrial tissue typically becomes less active during pregnancy and may not be as painful or large without hormonal stimulation. However, in some cases, once the pregnancy and breastfeeding end and menstruation returns, symptoms may also return.
If endometriosis has caused infertility, you have several treatment options, including surgery and drugs to stimulate ovulation, with or without intrauterine insemination or in vitro fertilization. The appropriate approach would be based on the results of a complete evaluation including an assessment of the male partner. In general, medicines that suppress the painful symptoms of endometriosis, such as GnRH agonists, oral contraceptives and danazol, do not improve the likelihood of pregnancy.
Prevention
Prevention
There is no known way to prevent endometriosis. However, some health care professionals believe there might be a certain level of protection against the disease if you begin having children early in life and have more than one child.
Additionally, you may prevent or delay the development of endometriosis with an early diagnosis and treatment of any menstrual obstruction, a condition in which a vaginal cyst, vaginal tumor or other growth or lesion prevents endometrial tissue from leaving your body during menstruation.
There also is some evidence that long-term birth control pill users are less likely to develop endometriosis.
Facts to Know
Facts to Know
Endometriosis is a noncancerous condition that affects at least 5 percent of reproductive-age women.
About 5.5 million women in the United States and Canada have been diagnosed with endometriosis.
Endometriosis develops when cells from the endometrium-or uterine lining-grow outside the uterus and stick to other structures, most commonly the ovaries, bowel, fallopian tubes or bladder. Endometrial tissue may migrate outside of the pelvic cavity to distant parts of the body. Researchers aren't sure what causes this condition.
Symptoms of endometriosis can range from mild pain to pain severe enough to interfere with a woman's ability to lead a normal life. Other symptoms include heavy menstrual bleeding, cramping, diarrhea and painful bowel movements during menstruation, and painful intercourse. However, you may have the disease and experience none of these symptoms.
A laparoscope is commonly used to diagnose and treat endometriosis. Laparoscopy allows a surgeon to view abnormalities in the pelvic region via a miniature telescope inserted through the abdominal wall, usually through the navel. While this is the best method of definitive diagnosis available, just because the doctor doesn't see any endometrial tissue doesn't rule out endometriosis.
Hormonal changes that occur during pregnancy can temporarily halt the painful symptoms of endometriosis since menstruation stops and estrogen levels drop.
There is no cure for endometriosis. Treatment options include minor and major surgery and medical therapies, including hormonal contraceptives and other hormonal drugs, such as GnRH (gonadotropin-releasing hormone) agonists, that limit the estrogen release that stimulates endometrial tissue growth.
There is some evidence that a family history of endometriosis may contribute to your likelihood of developing this disease. If you have a mother or sister who is battling endometriosis or has been diagnosed with it, your risk of developing the disease is 5 to 7 percent higher than someone with no family history.
Medical research indicates that daughters of women who took the drug diethylstilbestrol (DES) anytime from 1938 to 1971 to prevent miscarriage have an increased risk of developing this disease.
Questions to Ask
Questions to Ask
Review the following Questions to Ask about endometriosis so you're prepared to discuss this important health issue with your health care professional:
How many cases of endometriosis do you treat per month?
How do you make the diagnosis?
How many laparoscopic or laparotomy procedures do you perform each month?
Do you always use medical therapy before surgical therapy? If so, what therapies do you use?
Do you use GnRH agonists? If so, when? Before or after surgery?
What kinds of hormonal drug therapies have you used for patients with endometriosis?
Do you prescribe hormone therapy (HT) with GnRH agonist therapy? What are the risks and benefits of using HT for my health needs? Are there other options I can consider?
What side effects might I experience with the different hormonal therapies? How long do I have to be on these drugs for them to work effectively? Will my endometriosis come back when drug treatment ends?
Does endometriosis affect my ability to have children?
Do you think that alternative treatments-such as traditional Chinese medicines, changes in diet, homeopathy or allergy management-may help reduce the pain associated with endometriosis? Can you refer me to any practitioners who specialize in these areas and might be helpful to me?
When you perform laparoscopy for endometriosis, are you prepared to treat any disease that you see at that time or do you perform a diagnostic procedure only? What surgical approaches do you typically employ to treat endometriosis (for example, ablation, excision, laser, coagulation)?
Key Q&A
Key Q&A
What causes endometriosis?
The most widely accepted cause of endometriosis is retrograde menstruation. This occurs when tissue from the uterine lining, called endometrial tissue, flows backward through your fallopian tubes while you're menstruating. The tissue gets trapped and can't leave the body.
However, no matter where it is in the body, endometrial tissue still responds to your hormones each month. This tissue can become inflamed, bleed and develop into scar tissue. When the tissue is attached to organs in the pelvic and abdominal cavities, it may cause severe pain, infertility and other problems.
Other theories suggest that alterations in the immune system response, hormonal imbalances or environmental causes may be related to the development of endometriosis. Experts also find strong evidence suggesting a genetic link.
What does endometriosis feel like?
Pain in the pelvic region ranging from very mild to severe is the most common symptom, but you may not experience any symptoms. Some women describe the pain as sharp and burning. It may last all month long, but is usually worse during menstruation, deep penetration during intercourse or bowel movements. Other symptoms may include:
Diarrhea and painful bowel movements especially during menstruation
Abdominal tenderness
Intestinal pain
Abnormal menstrual bleeding
Severe menstrual cramps
Pelvic pain distinct from menstrual cramps
Backache
Pain during or after sexual penetration
Painful bowel movements
Pain with exercise
Painful pelvic examination
Infertility
How can I be sure I'm being diagnosed correctly if pain associated with the disease can often be confused with other medical problems?
Even without a definitive diagnosis, your health care professional may still prescribe hormonal treatments. If the pain decreases, there is an assumption that endometriosis was the cause of the pain. However, endometriosis cannot be definitively diagnosed without laparoscopy and biopsy.
Can I get pregnant if I have endometriosis?
Yes, you can. Nearly all women who have endometriosis are fertile, and there are many who have the disease and go on to have children.
Is there any way I can prevent endometriosis?
No. We don't know definitively what causes the condition so we don't know how to prevent it. Research suggests that having children early, having more than one child and long-term use of oral contraceptives may reduce the risk.
What options are available to treat endometriosis?
The most common medical therapies for endometriosis are hormonal contraceptives and other hormonal regimens, such as GnRH agonists (gonadotropin-releasing hormone drugs), which reduce estrogen release, limiting the effects of hormones on the endometrial tissue. Danazol, a synthetic androgen, is also used, but it can cause some undesirable side effects, including weight gain, hirsutism (hair growth) and lowering of the voice. Surgical treatments range from removing only the endometrial implants via laparoscopy to removing the uterus and ovaries.
How do I know which is the best treatment option for my case of endometriosis?
It's tough to know which treatment is best for you, especially because no comparative studies have been conducted to determine which approach is better. There are pros and cons for all treatments. Most women with the disease can find relief via medical therapies, and birth control pills may be used indefinitely to manage symptoms. Other women turn to surgery. However, many women try to avoid surgery to remove the uterus because it's a serious procedure that will leave them infertile and carries no guarantee of banishing endometriosis forever.
Because of the risks associated with surgery, the usual course of treatment is to proceed from the least invasive or risky to the more invasive treatment. That means medical treatment first.
If that doesn't work, your doctor may recommend laparoscopy, with surgery to remove the uterus as a last resort.
Lifestyle Tips
Lifestyle Tips
Boost intake of omega-3s
Animal research suggests that the omega-3 fatty acids found in fatty fish like mackerel, salmon, sardines and anchovies may help ease the pain of endometriosis. No research has been done on women with endometriosis to date, but some health care professionals recommend fish oil supplements to their patients with the condition. Fish oil has many other health benefits as well. Talk with your doctor about this option.
Block prostaglandin to relieve pain
Over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs) are enough to benefit many women with pain from endometriosis and may be the most helpful choice for you as well-check with your health care professional. Ibuprofen (Advil, Motrin, Rufen) and naproxen (Aleve, Anaprox, Naprosyn) are all examples. These drugs block prostaglandins. Prostaglandins are natural body substances that promote inflammation, uterine contractions and pain and are thought to be linked to endometriosis.
What to do when pain remedies don't work
Make sure your body is best able to withstand pain by getting enough sleep at night, eating right and taking recommended doses of vitamins and minerals-some studies suggest good results with magnesium or thiamine. A heating pad or hot bath may help ease painful cramps. Relaxation techniques, meditation and even acupuncture have helped some women-see a pain management specialist or visit a pain center. Other possibilities include prescription pain control drugs, hormone therapy, trancutaneous electrical stimulation (TENS) and surgery to remove endometriosis lesions, or to cut nerves transmitting pain.
Get help for painful intercourse
Tell your health care professional and ask for help, as painful intercourse is a symptom of endometriosis. Women typically feel pain during deep penetration, and some feel pain as if something has been "bumped into." Your health care professional will need to ask questions and perform a pelvic examination to find abnormalities and the source of tenderness. Ultimately, you may need a laparoscopy to document the presence of endometriosis lesions, and medication or surgery to relieve pain.
Prepare for Laparoscopy
Schedule your procedure at the end of the week, to take advantage of the weekend as part of your recovery time. The procedure is typically performed during the first half of the menstrual cycle before ovulation but after the menstrual flow has stopped. Clear your schedule for a few weeks afterward to allow as much time as possible for rest. Clean and take care of errands in advance, and lay in a supply of convenience meals. Arrange with your partner or an adult friend to help you with transportation on the day of surgery. Don't eat anything heavy or fatty the evening before, follow your doctor's preoperative instructions, leave jewelry and valuables at home and arrive early to fill out forms.
Petta CA, Ferriani RA, Abrao MS, et al. Randomized clinical trial of a levonorgestrel-releasing intrauterine system and a depot GnRH analogue for the treatment of chronic pelvic pain in women with endometriosis. Hum Reprod. 2005;20:1993-1998.
Mirena. Drugs.com. Revised August 2008. http://www.drugs.com. Accessed March 26, 2009.
"Endometriosis." The American College of Obstetricians and Gynecologists. http://www.acog.org. Accessed February 2009.
"Patient information: Endometriosis." Uptodate.com. Text can only be viewed with subscription. October 2008. www.uptodate.com. Accessed February 2009.
"Oral eicosapentaenoic acid supplementation as possible therapy for endometriosis." Fertil Steril. 2008 Oct;90(4 Suppl):1496-502. Epub 2007 Dec 3. http://www.ncbi.nlm.nih.gov. Accessed February 2009.
Berkowitz, Ross, Robert L. Barbieri, Andrea E. Dunaif. Kistner's Gynecology and Women's Health. 7th ed. St. Louis: Mosby, 1999. pp. 501-502.
"FDA Approves New Labels for Estrogen and Estrogen with Progestin Therapies for Postmenopausal Women Following Review of Women's Health Initiative Data." FDA News/Press Release. January 8, 2003. http://www.fda.gov. Accessed March 2003.
Grady D, Herrington D, Bittner V, et al, for the HERS Research Group. Heart and estrogen/progestin replacement study follow-up (HERS II): Part 1. Cardiovascular outcomes during 6.8 years of hormone therapy. JAMA 2002;288:49-57.
Hulley S, Furberg C, Barrett-Connor E, et al, for the HERS Research Group. Heart and estrogen/progestin replacement study follow-up (HERS II): Part 2. Non-cardiovascular outcomes during 6.8 years of hormone therapy. JAMA 2002;288:58-66.
Writing Group for the Women's Health Initiative Investigators. Risks and benefits of estrogen plus progestin in healthy postmenopausal women: principal results from the Women's Health Initiative randomized controlled trial. JAMA 2002; 288:321-333.
"Estrogen Plus Progestin Study Stopped Due to Increased Breast Cancer Risk, Lack of Overall Benefit." National Heart, Lung and Blood Institute. http://www.nhlbi.nih.gov. Updated July 9, 2002; accessed July 9, 2002.
"Women's Health Initiative," National Heart, Lung and Blood Institute. http://www.nhlbi.nih.gov. Updated July 9, 2002; accessed July 9, 2002.
"The Women's Health Initiative New Facts About: Estrogen/Progestin Therapy." National Heart, Lung and Blood Institute.http://www.nhlbi.nih.gov. Updated July 9, 2002; accessed July 9, 2002.
"Use of Hormone Replacement Therapy Questioned For Some Women: A Preliminary Response from The North American Menopause Society." http://www.nams.org. Updated July 9, 2002; accessed July 9, 2002.
Lacey JV, Mink PJ, Lubin JH, et al. "Menopausal Hormone Replacement Therapy and Risk of Ovarian Cancer." JAMA. 2002;288:334-341.368-369.
Droegemuller, William. "Endometriosis and Adenomyosis: Etiology, Pathology, Diagnosis and Management," in Comprehensive Gynecology, 4th Ed., Stenchever, Droegemuller, Herbst, Michell (2001), p. 531-564.
"About DES (diethylstilboestrol)" Endometriosis.org. http://www.endometriosis.org. Dated 1999. Accessed August 2001.
"Endometriosis Family Study Identifies High Risk of Cancer and Autoimmune Diseases." Endometriosis Association. http://www.endometriosis.org. Dated 1999. Accessed August 2001.
Guidelines on the Treatment of Endometriosis: Update. American College of Obstetricians and Gynecologists (ACOG). Practice Bulletin no. 11, Obstetrics and Gynecology, December 1999.
Reproductive Conditions-Endometriosis. Veritas Medicine. http://www.veritasmedicine.com. Dated 2001. Accessed August 2001.
The Endometriosis Association. http://www.endometriosisassn.org. July 2005.
Endometriosis.org http://www.endometriosis.org. July 2005.
Endometriosis. Mayo Clinic. Available at: http://www.mayoclinic.com. Accessed October 2005.
Berkley KJ, Rapkin AJ, Papka RE. The pains of endometriosis. Science. 2005 Jun 10;308(5728):1587-9.
Last date updated: Tue 2009-04-14
local clinic finder
Looking for free or low-cost health care? Find a health clinic in your area by clicking here.


