Endometriosis occurs when tissue similar to that which lines the inside of the uterus implants outside the uterine cavity. The endometrial growths respond to menstrual hormones in the same way as the uterine tissue, by building up, breaking down and then shedding. Since the tissue has no means of being expelled from the body, it develops into painful cysts or nodules at the areas of implantation.
The symptoms of the disease may vary widely between women, ranging from pain, usually around menstruation, to infertility.
The degree of symptoms does not always correlate with the severity of the disease.
The cause of endometriosis is unknown. Some women are however more at risk than others.
Although there is no certain cure for endometriosis, medication and/or surgery can provide relief of symptoms and may improve fertility outcomes.
The term endometriosis comes from the word ‘endometrium’ – the tissue that lines the inside of the uterus.
Endometriosis occurs when endometrial tissue implants in other areas of the body outside of the uterus.
Most of these tissue growths (also referred to as nodules, lesions or implants) are found in the ovaries and fallopian tubes. However, they can also occur in or on the intestine, bladder, bowel, vagina, rectum, cervix and vulva.
Although rare, endometriosis can occur outside the abdomen, in the lung, arm, thigh, skin and even the brain. If endometrial tissue appears within the muscle wall of the uterus, the condition is referred to as adenomyosis.
Endometrial growths are generally not cancerous; they are merely growths of normal tissue outside the normal location.
The endometrial tissue growths respond to menstrual cycle hormones in the same way as the uterus lining. Each month the tissue builds up, breaks down and then sheds.
While blood from the uterine cavity lining can leave the body through the cervix and vagina, bleeding from endometrial implants at all ectopic (out-of-place) sites becomes trapped.
This results in internal bleeding, inflammation, the formation of scar tissue and the formation of blood-containing cysts. With each menstruation these cysts expand and cause pain. It may also result in nodules that are associated with dyspareunia (pain during intercourse) or scarring with anatomical distortion and/or infertility.
The growths can rupture and spread to new areas. If they are on or near the bladder, bowels or intestine, they can interfere with their functions.
Some women remain unaffected by endometriosis, especially in the early stages. Others may suffer severe pain and discomfort. The symptoms seem to worsen with time, although cycles of remission and recurrence are the pattern in some cases.
The most common symptom of endometriosis is pain, usually in the lower abdomen and pelvic area. This pain can occur before and during menstruation, during or after sexual intercourse, during urination or bowel movements, while menstruating and in the lower back area.
The amount of pain or presence of symptoms is not related to the extent or size of the tissue growths, but rather to the location of the implants and the depth that the endometriosis has penetrated to into normal tissue.
Some women show no symptoms, while others suffer from debilitating pain and infertility.
The following are symptoms of endometriosis:
Pain before and during menstruation (dysmenorrhoea). Pain can begin a few days before the start of menstruation and is usually at its worst during the heaviest flow.
Pain during or after sexual intercourse (dyspareunia)
Painful urination or bowel movements during menstruation
Pelvic pain. This is usually caused by the collection of menstrual blood in the abdominal cavity, causing inflammation. If endometrial tissue implants on the appendix, the pain can appear over the right lower abdomen, similar to appendicitis.
Heavy or irregular periods
Backache during menstruation: this usually occurs when endometrial tissue implants on the intestine
Gastrointestinal upsets such as diarrhoea, cramping, constipation and nausea
Rectal bleeding or blood in stool
Blood in urine
Coughing up blood, particularly during menstruation (rare)
Shortness of breath or accumulation of air in the chest (rare)
Leg or hip pain
Fatigue, allergies and other immune system-related problems are also commonly reported complaints.
Because the symptoms of endometriosis are sometimes inconsistent and non-specific, it is possible to have some, all, or none of these symptoms.
The cause of endometriosis is not known. Various theories have been proposed, but no one theory seems to account for all cases.
It is thought that during menstruation, some pieces of uterine lining or endometrial tissue get pushed backwards up the fallopian tubes towards the ovaries and abdominal cavity. This tissue then implants itself and develops into endometriosis.
Another theory suggests that endometrial tissue is distributed to other parts of the abdomen and body by the lymph or blood system.
Endometriosis is often found in the abdominal surgical scars, giving rise to the theory that it is somehow transplanted during surgery. Endometriosis has, however, been found in such scars where accidental implantation seems unlikely.
Risk factors that influence each woman’s probability of developing endometriosis include familial or genetic inheritance, race, abnormal menstrual disorders, delayed childbearing, outflow obstruction, and impaired immune function.
Endometriosis cannot be prevented, especially if there is a family history of the disease. Using oral contraceptives may reduce the risk of developing endometriosis or prevent it from becoming worse. Although lifestyle modification and certain nutritional supplementation have been suggested to improve the symptoms of endometriosis, further research is still required to support their use.
Pregnancies before the age of 35 may be protective in some women.
The course of endometriosis is unpredictable. Although endometriosis is a chronic and usually progressive condition, the rate of progression varies from woman to woman.
Symptoms may remain stable, decrease, or increase with or without treatment. They may also disappear with treatment, but then return later.
Established criteria for classifying endometriosis are based on where the endometrial tissue is located, whether it is on or buried beneath an organ's surface, and whether growths are thin or dense ( American Fertility Society now known as American Society for Reproductive Medicine, ASRM)
The severity of endometriosis is determined after studying the uterus, fallopian tubes, ovaries, and the entire abdomen and pelvis through clinical examination (including rectal examination), pelvic imaging (ultrasound) and laparoscopy. It can be classified as minimal, mild, moderate, or severe, based on the AFS/ASRM scoring system
Stage one endometriosis is mild, where tissue growth is slight, scattered around the pelvic cavity and easy to treat.
Stage two is still mild, but is situated more deeply in the tissue.
Stage three endometriosis is moderate, with larger patches of endometrial tissue that is more widely spread. Cysts may be present.
Stage four is severe, where tissue growth is large and deep and most of the organs in the pelvic cavity are affected. The uterus and ovaries are often covered in scar tissue and the fallopian tubes may be blocked.
Endometrial tissue attached to an ovary or inside an ovary can form an endometrioma or ovarian cyst lined by endometrial tissue.
These cysts are also called chocolate cysts, because of the dark, red-brown blood inside.
As the endometriosis grows and sheds every month, the fluid inside the cysts accumulates and the cysts grow.
An endometrioma can rupture or leak, causing sudden, sharp abdominal pain. The material inside the cyst can adhere to surfaces within the abdominal cavity and may cause irreversible damage to the fallopian tubes. They may get infected and cause abscesses.
Other less common complications of endometriosis may include kidney impairment due to scar tissue build-up blocking urine flow or bowels. The growth of endometrial tissue in the lungs can cause the collapse of a lung, while growths in the brain or spinal cord can lead to seizures or paralysis.
Infertility and endometriosis
Possible reasons for the association includes, abnormal hormonal function, infrequent intercourse (pain), abnormal ovulation, affected sperm transportation, anatomical distortion with tubal blockage, impaired immunological function, and ovarian damage following surgical treatment..
The diagnosis of endometriosis starts with visiting a doctor and describing your symptoms, menstrual periods and how long you have had problems.
The doctor can perform a pelvic examination to feel whether any growths are detectable. It is important to visit the doctor during menstruation, or when the pain is greatest. Although this can be embarrassing, this is when the endometrial implants will be at their largest and easiest to feel.
There are three common types of endometriosis, peritoneal endometriosis, ovarian endometriosis (only on the surface or with cysts), and recto-vaginal endometriosis.
Peritoneal endometriosis is best diagnosed at laparoscopy. While ovarian cysts (endometrioma) are often seen on ultrasound. recto-vaginal endometriosis may need a combination of rectal examination, transvaginal or transrectal ultrasound and/or colonoscopy. The role of magnetic resonance imaging (MRI) in the diagnosis of endometriosis is not clearly established. CA 125 is not helpful in the diagnosis of endometriosis.
Laparoscopy is a surgical procedure done under general anesthesia. An incision is made into the abdomen (through the navel), and a telescopic instrument, called a laparoscope, is inserted so that the doctor can see the reproductive organs and abdominal cavity. One or two more 1cm incisions are also made to put instruments through, so that the internal organs may be manipulated and inspected. This is a “day case” procedure and the woman may go home within a few hours of the procedure, although she may not drive a vehicle for 24 hours after the anesthetic.
Because carbon dioxide gas is used to inflate the abdomen, so that organs can be safely visualized, the woman may feel some abdominal discomfort and shoulder pain (the gas irritates nerves on the diaphragm which lead to the shoulders) after the procedure, but this is transient and resolves after 24 to 48 hours.
If growths are found, a small sample of the tissue may be taken for examination at a laboratory, after which a diagnosis of endometriosis can be made. Generally this is not necessary, as endometriosis is diagnosed on naked eye inspection. Photographs (taken by attaching a camera to the laparoscope) are now more commonly taken. These are kept on record and allow the doctor to visually compare findings before and after treatment, should another laparoscopy be necessary later on. It also allows patients to share in visualizing their pelvis.
This procedure helps to determine the location, size, and extent of the growths, which can influence treatment options.
When to see a doctor
Women who experience mild symptoms of endometriosis, or who are approaching menopause, may decide to adopt a "watch and wait" approach. This involves waiting through several menstrual cycles to monitor the symptoms and to discuss them with their doctor during their next visit.
If a woman begins to experience pain that interferes with daily activities, pain during intercourse, pain during urination or bowel movements, blood in the urine or stools, or finds that she is unable to fall pregnant after trying for 12 months, she should consult a doctor.
Giving your doctor a good description of your symptoms is important. Describing all risk factors including a family history of endometriosis will assist your doctor in attempting to diagnose the disease.
Although there is no cure for endometriosis, a variety of treatment options exist. It is important to find a specialist who can prescribe the most appropriate form of treatment for the disease.
Medication can be prescribed to shrink the endometrial growths to control symptoms, or surgery may be necessary to remove the implants. A combination of surgery and medical therapy may also be used.
Deciding which treatment option to follow can be difficult, so it is important to evaluate the following:
Whether the symptoms are serious enough to require treatment
Whether you plan to have a child or more children
Whether you are close to menopause – symptoms should stop naturally after menopause. If you are close to menopause, it may be worthwhile to control the symptoms with medication until then.
Whether you prefer to treat your symptoms with medication or surgery
Whether a second opinion from a doctor would be useful
Ultimately the doctor will suggest the best treatment option. However the final decision will be made by the patient.
For mild symptoms, where infertility is not a threat, home treatment (as a supplement to professional care) may ease the pain and discomfort of endometriosis.
Painful menstrual periods are the most common symptom of endometriosis. To relieve menstrual pain:
Try an over-the-counter painkiller such as aspirin or ibuprofen. In some cases, however, prescription painkillers may be necessary.
Apply heat to the abdomen in the form of a hot water bottle or take warm baths. The heat will improve circulation and blood flow, and relieve pain.
Regular exercise also improves circulation and encourages the production of endorphins, the body’s natural pain relievers.
Hormone treatment aims to stop ovulation for as long as possible. This is achieved by using oral contraceptives including oestrogen and progesterone, progesterone alone (the two injectable contraceptives, Depo Provera® and Nur-isterate®), testosterone derivatives known as danazol and gestrinome, or a gonadotropin-releasing hormone drug (GnRH agonists).
An oral contraceptive or progesterone supplement may control endometriosis as long as the synthetic hormones are being used. The therapy can force endometriosis into remission for months or years after going off the hormones.
Danazol suppresses oestrogen levels and increases the amount of testosterone in the body. This prevents ovulation and menstruation, and shrinks the uterine lining, which prevents new endometrial implants. Due to its androgenic activity it is rarely used.
Many women find that this drug relieves the symptoms, but the side effects of this drug such as weight gain, acne, muscle cramps, vaginal dryness, body or facial hair growth, the deepening of the voice and water retention, can be a problem for some women. The drug increases the risk of birth defects, and should be prescribed in conjunction with contraceptives.
GnRH agonists should never be given as the first option because they are expensive and the side effects such as menopause symptoms and osteoporosis renders it less favourable compared to other hormonal treatments. In situation whereby there is a large cyst (endometrioma >5cm) surgical drainage followed by three months treatment with GnRH agonist before the second laparoscopy will be a recommended approach.
Levonorgestrel intra-uterine system (Mirena) may also be effective in the management of pain associated with endometriosis. Newer agents such as aromatase inhibitors (Letrozole or Anastrozole), receptor modulators, vascular disruptive agents, and invasion inhibitors are still largely experimental.
Medical therapy (hormonal or non-hormonal) does not improve fertility and therefore it should not be an option for a patient with endometriosis and who is infertile.
Women with endometriosis are often advised not to postpone pregnancy, as the more the disease progresses, the more likely it is to cause infertility.
Encouraging women to fall pregnant can be difficult, as this is a highly personal and life-changing decision.
Research that shows the likelihood of genetic links to endometriosis may also play a role, as women could pass on the risk of developing the disease to their offspring.
Pregnancy often causes a remission of endometriosis, as ovulation ceases, causing the growths to shrink.
But it is not a definitive cure - some women report relief from pain during pregnancy, while others report no relief at all. In many cases, endometriosis can return after pregnancy.
Surgery may be necessary to remove the growths if they are causing infertility or intestinal or bladder problems. Surgery does not always cure infertility, however, and is usually recommended for the treatment of endometriosis associated with infertility.
The principle of surgery is to remove all endometriotic lesions, restore the anatomy, and prevention of adhesions.
Any infertile woman who had surgery for endometriosis and trying to conceive must be offered assisted reproductive therapy (insemination, in vitro fertilization, or ICSI) if there is no pregnancy after six to twelve months after surgery, depending on the age of the woman, the duration of infertility, and other co-possible causes of infertility.
To get into the abdomen to treat endometriosis can be done through a laparoscope (key hole) or Laparotomy (open operation), but of course the benefits of laparoscopy is quick recovery and less scarring.
Surgery for minimal or mild endometriosis does improve a woman’s chance of having a baby, but the benefit of surgery in improving pregnancy rates in moderate and severe endometriosis is not clearly defined.
Peritoneal endometriosis, i.e. burning or removing the lesion has same results.
Endometrioma: Cystectomy (opening the cyst and taking it out without damaging the ovary) is preferable because it will reduce the chance of the cyst coming back and it is associated with an increased chance of conception. However if the cyst is > 5cm in size, to avoid potential damage to the ovary, it is better to drain the cyst and prescribe GnRH agonist for 3 months and then do a second laparoscopy to remove the cyst.
Recto-vaginal endometriosis: Surgical removal of the nodule will improve the pain and may also improve the chance of conception, by allowing more frequent intercourse. The involvement of colorectal surgeons must always be sought in deep, infiltrating rectal nodules for proper removal.
Resection of nerves has not been shown to improve pain associated with endometriosis.
Hormonal treatment such as contraception has not shown to be of significant benefit following surgery.
Hysterectomy with or without removal of the ovaries should only be done in women who have other problems associated with the uterus (womb). Hysterectomy, primarily for the treatment of endometriosis, will not offer any benefit and therefore should not be recommended.
Generally, the onset of menopause usually results in the decrease of endometriosis.
However, severe endometriosis can be reactivated by hormone replacement therapy or continued hormone production after menopause.
Traditional methods of treating endometriosis, such as Chinese medicine, homeopathy, massage and acupuncture have been suggested, but large body of evidence has failed to prove their benefit.
While there is no cure for the disease, adopting a healthier lifestyle – good nutrition, regular exercise - may improve the symptoms of endometriosis.
Previously reviewed by Carol Thomas, MBCHB(UCT), FCOG(SA), MMED(O&G)(UCT)
Reviewed by Dr Thabo Matsaseng, MB ChB, FCOG (SA), NMCP, Tygerberg Academic Hospital, University of Stellenbosch, October 2010