Endometriosis is a very common condition where cells of the lining of the womb (the endometrium) are found elsewhere, usually in the pelvis and around the womb, ovaries and fallopian tubes.

It mainly affects women during their reproductive years. It can affect women from every social group and ethnicity.

Endometriosis is not an infection and it is not contagious. Endometriosis is not cancer.

The main symptoms of endometriosis are pelvic pain, pain during or after sex, painful, sometimes heavy periods and, for some women, problems with getting pregnant.

Endometriosis can affect many aspects of a woman’s life including her general physical health, emotional wellbeing and daily routine.

Endometriosis is common and many women may have no symptoms. An estimated two million women in the UK have this condition.

Endometriosis is a long-term condition which affects women of all ages during their reproductive years (from the onset of menstrual periods to the menopause). It affects women from all social and ethnic groups.

Women who do experience symptoms may have one or more conditions:

• Painful periods (dysmenorrhoea) which do not respond to over-the-counter pain relief. Some women have heavy periods.
• Pain during or after sexual intercourse (dyspareunia)
• Lower abdominal pain
• Pelvic pain which can be long-term
• Difficulty in getting pregnant or infertility
• Pain related to the bowels and bladder (with or without abnormal bleeding)
• Long-term fatigue.

Some women do not have any symptoms at all.

Pain is a common symptom of endometriosis. The pain can be a dull ache in the lower abdomen, pelvis or lower back. Pain affects each woman differently: where it hurts, when it hurts and how much it hurts. The pain, and the effects of endometriosis, can make you feel depressed.

Most women with endometriosis get pain in the area between their hips (known as the pelvis) and the tops of their legs. For further information see Long-term pelvic pain: information for you. Some women get pain only at certain times, such as during their periods, when they have sex or when they open their bowels. Other women have pain all the time.

Some women with endometriosis become pregnant easily while others have difficulty getting pregnant. The pain may get better during pregnancy and then recur after the birth of the baby. Some women find that their pain resolves without any treatment.

What causes endometriosis?

During the menstrual cycle, under the influence of the female hormones estrogen and progesterone, the lining (endometrium) of the womb thickens in readiness for a fertilised egg. If pregnancy does not occur, the lining is shed as a period.

Endometriosis occurs when the cells of the lining of the womb are found in other parts of the body, usually the pelvis. Each month this tissue outside the womb thickens and breaks down and bleeds in the same way as the lining of the womb. This internal bleeding into the pelvis, unlike a period, has no way of leaving the body. This causes inflammation, pain and damage to the reproductive organs.

Reproductive areas where endometriosis can be found

Endometriosis commonly occurs in the pelvis. It can be found:

• On the ovaries where it can form cysts (often referred to as ‘chocolate cysts’)
• In or on the fallopian tubes
• Almost anywhere on, behind or around the womb
• In the peritoneum (the tissue that lines the abdominal wall and covers most of the organs in the abdomen).
• Less commonly, endometriosis may occur on the bowel and bladder, or deep within the muscle wall of the uterus (adenomyosis). It can also rarely be found in other parts of the body.

 Why does endometriosis occur?

It is not yet known why endometriosis occurs. A number of theories have been suggested but none has been proved. The most commonly accepted theory is that, during a period, light ‘backward’ bleeding carries tissue from the womb to the pelvic area via the fallopian tubes. This is called ‘retrograde menstruation’.

How soon can I expect to get a diagnosis?

For many women, it can take years to get a diagnosis. Doctors say that this is because:

• No one symptom or set of symptoms can definitely confirm a diagnosis of endometriosis
• The symptoms of endometriosis are common and could be caused by a number of other conditions such as irritable bowel syndrome (IBS) and pelvic inflammatory disease (PID) (for further information see Acute pelvic inflammatory disease: what the RCOG guideline means for you)
• Different women have different symptoms
• Some women have no symptoms at all

There is no simple test for endometriosis. The only way to make a definite diagnosis is by a small surgical operation known as laparoscopy (see What treatment can I get?). This is not performed on every woman.

If you have painful periods and no other symptoms, your GP may suggest that you try pain relief before having further surgical investigation or treatments.

Living without a diagnosis can be distressing. Many women may fear the worst about why they are in pain or why they are having problems becoming pregnant. They may think that they have cancer (s

What happens when I see a specialist?

At your appointment, you may be asked specific questions about your periods and your sex life. It is important that you provide as much information as possible, as this will help your doctor find the correct diagnosis. You may find it helpful to write down your symptoms beforehand and take your notes along to the appointment with you. In this way, you will be sure to provide all the information required. Some women find it helpful to take a friend or partner along with them as well.

You should also have an opportunity to ask questions (for further information see BestTreatment NHS Direct in Useful organisations).

Your gynaecologist may examine your pelvic area, this will include an internal examination. Your doctor will discuss the best time to do this. This may be when you are having your period. If you have concerns about this, you should have an opportunity to discuss them.

 What types of tests might I be offered?

You should be given full information about the tests that are available. These may include:

Ultrasound

You may be offered a scan. This can identify whether there is an endometriosis cyst in the ovaries. A normal scan does not rule out endometriosis.

Laparoscopy

For most women, having a laparoscopy is the only way to get a definite diagnosis; because of this, it is often referred to as the ‘gold standard’ test. A laparoscopy is a small operation which is carried out under general anaesthesia. A small cut is made in your abdomen near your tummy button (navel), then a telescope (known as a laparoscope), which is about the width of a pen, is inserted. This allows the gynaecologist to see the pelvic organs clearly and look for any endometriosis. This is usually carried out as day surgery.

As with any surgical procedure, there are risks and benefits. These should be fully explained to you when you are offered the test (see Are there any risks?).

If you have a laparoscopy, you should be given full information about your results.

Making a decision about treatment

You should be given full information about your options for treatment. This should also include information about the risks and benefits of each option.

Several factors may influence your decision about treatment. These include:

• How you feel about your situation
• Your age
• Whether your main symptom is pain or problems getting pregnant
• Whether you want to become pregnant – some hormonal treatments which help to reduce the pain will stop you from becoming pregnant
• How you feel about surgery
• What treatment you have had before
• How effective certain treatments are

You may decide that no treatment is the best way forward. This could be because your symptoms are mild, you have not had problems getting pregnant or you are nearing the menopause, when symptoms may get better.

What treatment can I get?

The options for treatment may be:

Pain relief

Pain-relieving drugs reduce inflammation and help to ease the pain.

Hormone treatments

There is a range of hormone treatments to stop or reduce ovulation (the release of an egg) to allow the endometriosis to shrink or disappear.

The hormonal methods below are contraceptives and will prevent you from becoming pregnant:

• The combined oral contraceptive (COC) pill or patch
• These contain the hormones estrogen and progestogen and work by preventing ovulation and can make your periods lighter, shorter and less painful.
• The intrauterine system (IUS): this is a small T-shaped device which releases the hormone progestogen. This helps to reduce the pain and makes periods lighter. Some women get no periods at all.
• The hormonal methods below are non-contraceptive, so contraception will be needed if you do not want to become pregnant:
• Use of hormonal progestogens or testosterone derivatives
• GnRH agonists – these drugs prevent estrogen being produced by the ovaries and cause a temporary and reversible menopause.

Surgery

Surgery can be used to remove areas of endometriosis. Surgery including hysterectomy does not always successfully remove the endometriosis. There are different types of surgery, depending on where the endometriosis is and how extensive it is. How successful the surgery is can vary and you may need further surgery. Your gynaecologist will discuss this with you before any surgery.

Laparoscopic surgery

The gynaecologist removes patches of endometriosis by destroying them or cutting them out.

Laparotomy

If the endometriosis is severe and extensive, you may be offered a laparotomy. This is major surgery which involves a cut in the abdomen, usually in the bikini line.

Hysterectomy

Some women have surgery to remove their ovaries or womb (a hysterectomy). Having this surgery means that you will no longer be able to have children after the operation. Depending upon your own situation, your doctor should discuss hormone replacement therapy (HRT) with you if you have your ovaries removed.

What if I am having difficulty getting pregnant?

Getting pregnant can be a problem for some women with endometriosis. Your doctor should provide you with full information about your options such as assisted conception. Infertility Network provides information about this (see Other organisations).

Are there any side effects?

You will be given full detailed information about the risks and benefits of any investigation, surgical procedure and treatment suggested. The side effects will vary from woman to woman.

Living with endometriosis

Not all cases of endometriosis can be cured and for some women there is no long-term treatment that helps. With support many women find ways to live with and manage this condition.

Support organisations provide invaluable counselling, support and advice (see Other organisations).

Complementary therapies

Complementary therapies include reflexology, traditional Chinese medicine, herbal treatments and homeopathy. They may be effective at relieving pain. Many women have found that dietary changes such as eliminating certain food types, such as dairy or wheat products, may help to relieve symptoms. Therapies such as TENS, acupuncture, vitamin B1 and magnesium help some women with painful periods. There is currently insufficient evidence to show whether such therapies are effective at relieving the pain associated with endometriosis.

Is there anything else I should know?

• Taking the combined oral contraceptive (COC) pill or contraceptive patch treats the symptoms of endometriosis.
• If you become pregnant, endometriosis is unlikely to put your pregnancy at risk.
• Some women find that recreational exercise improves their wellbeing, which may help to improve some symptoms of endometriosis (for further information see Recreational exercise and pregnancy: information for you)
• No treatment is guaranteed to work all the time for everyone.
• Support groups are run locally for women with endometriosis
• Internet forums may be the first place many women turn to for support. The quality of information can be variable.

Sources and acknowledgements

This information is based on the Royal College of Obstetricians and Gynaecologists (RCOG) guideline The Investigation and Management of Endometriosis, originally published by the RCOG in July 2000 and revised in October 2006. The information in this leaflet will be reviewed and updated, if necessary, once the guideline has been reviewed. The guideline contains a full list of the sources of evidence we have used.

Clinical guidelines are intended to improve care for patients. They are drawn up by teams of medical professionals and consumers’ representatives, who look at the best research evidence there is about care for a particular condition or treatment. The guidelines make recommendations based on this evidence.

This information has been developed by the Patient Information Subgroup of the RCOG Guidelines and Audit Committee, with input from the Consumers’ Forum and the authors of the clinical guideline. It was reviewed before we published it by women attending clinics in Cambridge, London and Oxford. The final version is the responsibility of the Guidelines and Audit Committee of the RCOG.

It’s estimated that 40 to 50 percent of infertile women may have endometriosis. Endometriosis may be related to infertility in several ways:

• Women who experience deep pain during intercourse may choose to have intercourse less often, reducing the likelihood of becoming pregnant.
• Scar tissue from endometriosis can form adhesions around the ovary and restrict the available surface area of the ovary for egg release.
• Adhesions affecting the fallopian tubes may interfere with their ability to pick up an egg released by an ovary and transport it to the uterus.
• Occasionally, endometriosis will form inside the fallopian tube, resulting in blockage and making fertilization impossible.
• Endometriosis can disrupt the ovaries’ normal cycle of egg development and release.
• The peritoneal fluid in women with endometriosis contains an increased number of scavenger cells, which have the ability to destroy sperm cells, making fertilization unlikely.

Becoming Pregnant After Treatment

Pregnancy rates following various treatments for endometriosis vary between about 35 percent and 65 percent. Research has shown that for women with minimal or mild endometriosis, there is no proven benefit from medical or surgical treatment versus no treatment at all. Also, the more endometriosis a patient has, the less likely she is to become pregnancy following treatment.

Pregnancy rates are highest in the first one to two years following treatment. If danazol is used together with surgical treatment, pregnancy rates tend to be better when the medication is given before the surgery.

Women who only have minimal or mild endometriosis and who are pain-free will not overall have their fertility prospects improved by having their endometriosis treated. However, if no other cause of infertility is identified, it is reasonable to offer treatment to prevent the endometriosis from progressing. Laparoscopic surgery may be the best treatment in this case.

Infertile patients with moderate or severe endometriosis should be treated even if they have little pain. A six-month course of danazol or GnRH agonists followed by conservative surgery is probably the most effective treatment. Alternatively, conservative (laparoscopic) surgery alone may be used.

Infertility Treatments

Infertility treatments can increase the chances of pregnancy in women with endometriosis . The first step often involves the use of medication to boost the ovaries’ production of eggs. This is combined with inserting male sperm directly into the uterus.

If a woman does not become pregnant within one to two years, she may wish to explore assisted conception. This can be of two types:

• In-Vitro Fertilization (IVF) is a method for treating infertility in which an egg is surgically removed from the ovary and fertilized with the man’s sperm outside the body. If all goes well, the eggs fertilize and the resulting embryos are transferred to the women’s uterus two days later. This is often done if a woman has blocked fallopian tubes.
• Gamete Intrafallopian Transfer (GIFT) involves putting eggs and sperm into the fallopian tubes to be fertilized there. This method is suitable for woman with healthy fallopian tubes.

The decision to try assisted conception techniques may be particularly appropriate for women over age 35. Good pregnancy rates have been reported for both of these techniques, although the success rate was lower in women with severe endometriosis.

In some women, endometriosis causes no symptoms or mild symptoms and does not need to be treated at all. However, untreated endometriosis can continue to worsen, so these women should continue to have regular examinations to monitor the condition.

If endometriosis is causing symptoms or is interfering with a woman’s ability to become pregnant, several treatment options are available:

• Medication
• Conservative surgery
• Hysterectomy

Need To Know:

Medication usually is recommended for women with mild to moderate symptoms. Surgery for endometriosis is usually necessary for women with:

• Patches of endometrial tissue larger than 1 ½ to 2 inches in diameter
• Significant adhesions in the lower abdomen or pelvis
• Endometrial tissue that obstructs one or more fallopian tubes
• Endometriosis that is causing severe lower abdominal or pelvic pain that can’t be relieved with medication.

Which Treatment Is Best for You?

Treatment of endometriosis varies depending on the extent of the condition and a woman’s plans for childbearing.

• In women with mild to moderate endometriosis, medication can significantly or even completely relieve their symptoms. However, medication cannot cure endometriosis. In some cases, the pain will return about six months after the medication has stopped.
• In women with moderate to severe endometriosis who wish to preserve their ability to become pregnant in the future, conservative surgery such as laparoscopy would usually be required as well.
• In women with severe endometriosis who do not wish to have any or additional children, a hysterectomy will offer permanent relief. Hysterectomy also is an option for women with moderate endometriosis who have completed childbearing and women whose symptoms keep coming back after other treatments have been tried.

Need To Know:

Women with endometriosis who want to get pregnant are advised not to delay childbearing for too long, because the repeated scarring and adhesions caused by endometriosis may cause infertility (an inability to conceive). The chances for conceiving are highest in the first two years following treatment for endometriosis.

Medications To Treat Endometriosis

For women with mild to moderate symptoms, medication may be the best treatment option. A course of medication is also sometimes prescribed along with conservative surgery.

Medications to treat endometriosis include:

• Pain relievers
• Hormonal treatments
• Oral contraceptives
• Progesterone
• Danazol
• GnRH agonists

Pain Relievers

Over-the-counter pain relievers may include aspirin, acetaminophen (such as Tylenol), ibuprofen (such as Advil), naproxen sodium, indomethecin, and tolfenamic acid. In some cases, prescription pain-killing medication may be helpful.

Hormonal Treatments

Hormonal treatment is the mainstay of prescription medication for endometriosis. Treatment with medication is based on two important observations:

• The symptoms of endometriosis tend to improve during pregnancy.
• The symptoms of endometriosis tend to improve after menopause .

From these observations, two treatments have evolved:

• Pseuodopregnancy medical therapies, which are drugs that fool the body into thinking it is pregnant. These include oral contraceptives and progesterone.
• Pseudomenopause medical therapies, which are drugs that fool the body into thinking that it is past menopause. These include danazol and GnRH agonists.

Oral Contraceptives

When it was introduced, pseudopregnancy therapy (fooling the body into thinking it is pregnant) with high-dose birth control pills was an important advance in the treatment of endometriosis. This approach is used less now, since the introduction of other treatments.

However, in some women, oral contraceptives (birth-control pills) are the best option. The type of oral contraceptive used is the combination birth control pill (which contains two female hormones, estrogen and progestin).

Oral contraceptives cannot cure endometriosis, but they can be effective in temporarily relieving the pain. They do this by stopping the monthly hormonal cycle, which causes the endometrial tissue to swell.

Minor side effects include abdominal swelling, breast tenderness, increased appetite, ankle swelling, nausea, and bleeding between periods. In rare cases, oral contraceptives can cause deep vein thrombosis (blood clots).

Need To Know:

Research has proven that smoking and taking oral contraceptives (birth control pills) significantly increases a woman’s risk for stroke. Together, they can cause blood clots to form. Women who smoke should not take oral contraceptives.

Progesterone

Progesterone is one of the female sex hormones produced by the ovary that prepares the lining of the uterus for implantation of a fertilized egg. Given orally or by injection, progesterone induces a simulated state that mimics pregnancy. This relieves the symptoms of endometriosis by stopping the monthly swelling and discharge of the endometrial tissue.

Progestogens (drugs with properties similar to progesterone) that are used for treating endometriosis include medroxyprogesteron acetate, norethisterone, and norgestrel. Many women respond well to this treatment, but some experience side effects that include:

• Irregular menstrual bleeding (a common side effect)
• Weight gain
• Acne
• Mood swings
• Depression

Danazol

Since its introduction in 1971, danazol has become the main drug treatment for endometriosis.

Unlike oral contraceptives and progesterone, which induce a pregnancy-like state, danazol is a synthetic male hormone that relieves the pain of endometriosis by temporarily stopping the monthly hormonal cycle that causes endometrial tissue to swell.

Although it is true that danazol is a synthetic hormone, it can be thought of as an “anti-hormone,” since many of its actions oppose the effects of estrogen, the main female hormone. Although danazol does not increase the total amount of testosterone (male hormone) in a woman’s body, it renders it more biologically active.

Need To Know:

Because danazol can be harmful to a fetus if taken during pregnancy:

• A woman should begin taking it on the first day of a period to ensure that she is not pregnant, and
• A woman and her partner should use effective birth control methods to ensure a pregnancy does not occur while she is taking danazol.

Danazol is a very effective medication; it improves the symptoms of endometriosis in more than 95 percent of the women who take it. It is usually taken for six months. However, danazol can produce a number of side effects, including:

• Acne
• Greasy skin
• Weight gain
• High cholesterol levels
• Increase in body hair growth
• Voice changes
• Disruption of menstrual cycle
• Hot flushes and sweats
• Reduced sex drive
• Indigestion and stomach upsets
• Dizziness
• Reduced breast size
• Muscle cramps
• Irritability
• Headaches
• Tiredness

However, only a small percentage of women (5 to 10 percent) chose to discontinue danazol because of side effects. Most do not experience major problems and can complete the course of treatment. Women who become pain-free while on danazol often feel very well.

Treatment with danazol usually lasts six to nine months. Any side effects from danazol are reversible, and women will often tolerate them in exchange for the relief of the pain caused by endometriosis. When the medication is stopped, a woman’s fertility (ability to become pregnant) returns in two to three months.

Need To Know:

Danazol should not be taken by:

• Women who are or may be pregnant
• Women who are breast-feeding
• Women with occupations dependent on voice quality, such as singers, because there is a small risk of voice changes

Also, women who experience migraine headaches should be aware that the migraines might worsen during treatment.

GnRH Agonists

GnRH agonists is an abbreviation for gonadotropin-releasing hormone analogues. The role of this group of drugs is to suppress the pituitary gland .

The pituitary gland normally produces hormones that act on the ovary, which in turn produces the female sex hormones, estrogen and progesterone. By “turning off” the pituitary, the ovary is also “turned off.” As a result, the ovaries stop ovulating and no longer produce estrogen. The overall effect is termed “medical menopause.”

This group of drugs is proven to be effective in treating endometriosis, but they also tend to produce side effects that include:

• Vaginal dryness
• Mood swings
• Hot flashes (a more common side effect)

Unlike danazol, they do not raise cholesterol levels. But they do cause calcium loss from bone, which can result in osteoporosis . Less common side effects include decreased sex drive, reduced breast size, bloating, and excess hair growth.

The GnRH agonists (known also as GnRH analogues) are given as a monthly injection or daily nasal spray and have become a popular (although more expensive) alternative to danazol. These drugs include Lupron, Synarel, and Zoladex.

As with danazol, GnRH agonists should not be taken during pregnancy, so effective contraception methods should be used. A woman’s menstrual period will resume about two months after discontinuing the medication, and fertility usually returns in one to two months.

Conservative Surgery

Surgery may be considered for women with severe pain whose symptoms are not relieved with medication. For these women, the treatment can be tailored depending on whether they want to be able to have children. Conservative surgery can help preserve a woman’s ability to become pregnant.

Conservative surgical procedures include:

• Laparoscopy
• Laparotomy
• Laser surgery
• Electrocautery

Conservative surgery for endometriosis is performed to remove areas of endometriosis and to divide adhesions without removing the uterus or the ovaries. It is offered to women who wish to be able to have children in the future.

One problem with conservative surgery is that it usually provides only a temporary measure of relief, as endometriosis recurs in most women.

Nice To Know:

Very often, conservative surgery will be performed after a course of danazol or GnRH agonists, as the results of surgery tend to be better.

Laparoscopy

When a laparoscopy is done to confirm a diagnosis of endometriosis, the endometrial tissue can be removed at the same time. Laparoscopy is performed by inserting a pencil-thin instrument through an incision in the abdomen (usually in the belly button). It gives the physician an exceptionally clear view, on a television monitor, of the inside of the abdominal cavity.

The physician can pass other instruments through the same incision, or through other tiny incisions, to remove the misplaced endometrial tissue.

Laparotomy

In laparotomy, an incision is made in the abdomen and the abdominal cavity is opened and explored for signs of disease. Any endometrial tissue is removed, and the incision is then closed.

Laparotomy is major surgery that requires a brief hospital stay and three to four weeks of recuperation afterwards. This procedure is not performed as commonly as laparoscopy.

Laser Surgery

A laser is a device that concentrates light into an intense beam to produce heat that can destroy misplaced endometrial tissue. A variety of lasers can be used for treating endometriosis during laparoscopy. Although laser surgery is an important advance, it has not been shown to be superior or safer than other laparoscopic methods that destroy tissue, such as the use of electrical probes or direct heat.

Electrocautery

This procedure uses an electrical current to produce heat and destroy the patches of endometrial tissue. As with laser surgery, electrocautery is performed during laparoscopy.

Hysterectomy

Hysterectomy, the most radical treatment for endometriosis, involves surgically removing the uterus, both ovaries and both fallopian tubes, along with as many areas as possible of misplaced endometrial tissue.

A hysterectomy can be performed by making a cut (incision) in your abdomen, which exposes the organs and tissues that need to be removed. This is called an abdominal hysterectomy. During the procedure, a woman will have general anesthesia and will be asleep.

A hysterectomy also can be performed through the vagina (vaginal hysterectomy), which eliminates the need for an abdominal incision. However, in women with endometriosis, an open incision allows the surgeon the opportunity to better view the abdominal cavity to look for and remove areas of endometriosis.

The major advantage of hysterectomy is that it is very effective, and recurrences of endometriosis are rare. After a hysterectomy, a woman will no longer have menstrual periods and may experience symptoms of menopause. However, those symptoms can be controlled with hormone replacement therapy and other medication.

Here are some frequently asked questions related to endometriosis.

I have endometriosis. Could my daughters inherit it?

•  Endometriosis does appear to run in families, and your daughters might inherit the tendency to develop it. This would put them at higher-than-average risk for the disorder.

How can you tell the difference between normal menstrual pain and pain from endometriosis?

• This sometimes is not easy. Generally, though, normal menstrual pain starts at the beginning of the flow and lasts one or two days. Pelvic pain from endometriosis tends to occur before the flow starts and may last several days.

How can a physician tell the difference between such gastrointestinal disorders as irritable bowel syndrome (IBS) and endometriosis that may affect the bowel?

• Again, the difference between the symptoms caused by these two conditions may be difficult to discern. Pain from IBS usually follows along the tract of the large intestine, and also may be accompanied by diarrhea, constipation, and gas and bloating. If the pain occurs with an obvious trigger, like eating, it is more likely IBS; if it occurs during the time of menstruation , endometriosis is a more likely diagnosis.

I’m in my early 30s and I want to have children. Since I have endometriosis, my doctor has advised me to have children sooner, rather than later. Why?

• Endometriosis is a progressive disorders. Since it is associated with infertility , and infertility increases generally after the age of 35, most doctors advice women with endometriosis to try and get pregnant before that age.