Published by Bupa's health information team, May 2009.
This factsheet is for people who have endometriosis, or who would like information about it.
Endometriosis is where cells like the ones found in the womb lining (endometrium) grow on organs outside the womb. These cells go through the same monthly changes as the womb lining itself, sometimes swelling and bleeding into the body cavity.
Endometriosis (pronounced "en-doh-mee-tree-oh-sis") is usually found in women aged between 25 and 49; it's rare in women under 20. It's estimated that up to 15 out of 100 premenopausal women have endometriosis.
Endometriosis is most common on the ovaries, fallopian tubes and the tissues that hold your womb in place. You can also get endometriosis on or around other organs in your pelvis and abdomen (tummy), such as your bladder or bowel. Rarely, endometriosis can occur in the space around your lungs or heart.
Endometriosis can cause cysts (endometrioma) to form on the ovaries. These cysts may not cause you any pain - you may only find out about them during an internal examination to check your fertility.
In some women, endometriosis gets better on its own, but for most, it gets worse without treatment.

The womb and surrounding structures
The symptoms of endometriosis can vary. Some women have no symptoms at all, while others have severe pain. The most common symptom is pelvic pain that feels like period pain.
Other symptoms include those listed below.
Endometriosis on the bowel may cause swelling of your lower abdomen, pain when you have a bowel movement or blood in your faeces during a period. Endometriosis on the bladder can cause pain when you urinate or blood in your urine during a period. Symptoms of endometriosis usually disappear after the menopause.
Complications of endometriosis include those listed below.
No one knows for certain what causes endometriosis or why some women get it and others don't. Endometriosis can affect any woman of childbearing age.
You're more likely to develop endometriosis if you:
Your GP will ask you about your symptoms and examine you. He/she may also ask you about your medical history. Your GP may wish to perform a vaginal examination. If he/she thinks you may have endometriosis, he/she will refer you to a gynaecologist (a doctor specialising in women's reproductive health).
The only way to be sure that you have endometriosis is to have a laparoscopy. A laparoscopy is a procedure that allows your surgeon to look inside your abdomen. The procedure involves passing a narrow, flexible, tube-like telescopic camera (a laparoscope) into your abdomen through a small cut. Your surgeon will examine the organs in your pelvis by looking at pictures sent to a monitor.
The diagnostic procedure takes about 30 minutes and is usually done as a day case under general anaesthesia. This means you will be asleep during the procedure. You will be asked to follow fasting instructions. Typically you must not eat or drink for about six hours before a general anaesthetic. However, some anaesthetists allow occasional sips of water until two hours beforehand. You usually won't need to stay overnight in hospital.
If you have mild or moderate endometriosis, the affected tissue can sometimes be removed at the same time, which may prolong your procedure. If your surgeon finds that you have severe endometriosis, he or she may remove a small piece of the endometrial tissue for testing in a laboratory to confirm that it's endometriosis and not cancer.
There is currently no cure for endometriosis, but treatments are available for managing the symptoms. These aim to:
Medicines used to treat endometriosis don't improve fertility, but surgery can help if the endometriosis is interfering with the normal workings of the womb and ovaries. Some women with endometriosis who want to have children may need fertility treatment.
The type of treatment you have will depend on your age, the severity of your symptoms and whether or not you want to have children.
You can take over-the-counter medicines, such as ibuprofen. Always read the patient information that comes with your medicine and if you have any questions, ask your pharmacist for advice.
Hormonal medicines that reduce the amount of oestrogen in your body will reduce the size of the endometriosis and ease your symptoms. Some examples are:
The combined oral contraceptive can also be used, but it isn't licensed for the treatment of endometriosis. Prescribing outside the licence is called off-label use. This means the medicine is being used to treat a condition for which the medicine has not been licensed and isn't listed in the patient information leaflet that comes with your medicine. Your doctor can legally prescribe outside the licence if he or she feels the medicine will be effective for you.
These hormonal treatments all have different side-effects. Your doctor may suggest trying several hormonal medicines to find one that works best for you. Always ask your doctor for advice and read the patient information leaflet that comes with your medicine.
Hormonal medicines (but not oral contraceptives or GnHR analogues) can harm a developing baby, so you should use a barrier method of contraception (such as condoms) to prevent you becoming pregnant while taking these medicines.
Treatment with medicines won't cure endometriosis and symptoms usually return when you stop taking them.
The aim of surgery is to remove as much of the endometriosis as possible while still enabling you to have children. You may need surgery if:
The endometriosis may be cut away, or it can be destroyed with heat from an electric current or a laser (endometrial ablation). This can usually be done by a procedure called laparoscopy (the same procedure you will have had during your diagnosis). Your surgeon will make small cuts in your abdomen and then use a laparoscope to view the inside of the pelvis and remove the endometriosis (this is called keyhole surgery).
There's a chance your surgeon may need to convert your keyhole procedure to open surgery. This means making a bigger cut on your abdomen. This is only done if it's impossible to complete the operation safely using the keyhole technique. Your surgeon will give you more information about which option is best for you.
In some women endometriosis can come back after surgery. Your surgeon may recommend you take hormonal medicines after the surgery to help delay the return of symptoms.
Some women find that complementary treatments such as acupuncture, aromatherapy, herbal remedies and homeopathy are helpful for relieving pain. However, there is no clinical evidence to support this. Your GP can advise you on these treatments and refer you to a qualified practitioner.
Your doctor may use ultrasound, X-ray or MRI (magnetic resonance imaging) to look inside your pelvis and monitor how the endometriosis is responding to treatment.
This information was published by Bupa's health information team and is based on reputable sources of medical evidence. It has been peer reviewed by Bupa doctors. The content is intended for general information only and does not replace the need for personal advice from a qualified health professional.
Publication date: May 2009
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