Endometriosis is a common condition in which small pieces of the womb lining (the endometrium) are found outside the womb. This could be in the fallopian tubes, ovaries, bladder, bowel, vagina or rectum.
Endometriosis affects around 2 million women in the UK. Most of them are diagnosed between the ages of 25 and 40.
Endometriosis is a long-term (chronic) condition that causes painful or heavy periods. It often causes pain in the lower abdomen (tummy), pelvis or lower back. It may also lead to lack of energy, depression and fertility problems.
However, the symptoms of endometriosis can vary and some women have few symptoms or no symptoms at all.
If your GP suspects that you have endometriosis they will refer you to a gynaecologist (specialist in the female reproductive system). The gynaecologist may carry out an examination of your fallopian tubes, ovaries and womb, known as a laparoscopy, to check for patches of endometriosis.
Read more about diagnosing endometriosis.
What causes endometriosis?
The causes of endometriosis are not fully known, but there are several theories. The most common theory is that the womb lining does not leave the body properly during a period and embeds itself onto the organs of the pelvis. Doctors refer to this as retrograde menstruation.
The endometriosis cells behave in the same way as those that line the womb, so every month they grow during the menstrual cycle and bleed.
Normally, before a period, the hormone oestrogen causes the endometrium to thicken to receive a fertilised egg. If the egg isn’t fertilised, the lining breaks down and leaves the body as menstrual blood (a period).
Endometriosis tissue anywhere in the body will go through the same process of thickening and shedding, but it has no way of leaving the body. This leads to pain, swelling and sometimes damage to the fallopian tubes or ovaries, causing fertility problems.
Treating endometriosis
There is no known cure for endometriosis. However, the symptoms can often be managed with painkillers or hormone treatments, which help prevent the condition from interfering with your daily life. Surgery can sometimes be used to improve symptoms and fertility.
A healthy diet can improve energy levels and help regulate bowel movements and sleep patterns.
Pregnancy sometimes reduces the symptoms of endometriosis, although symptoms often return once the menstrual cycle returns to normal.
Read more about how endometriosis is treated.
Endometriosis can be a difficult condition to deal with both physically and emotionally. Charities such as Endometriosis UK and the SheTrust can offer advice and support to help you cope.
Endometriosis and pregnancy
One of the main complications of endometriosis is difficulty getting pregnant, or not being able to get pregnant (infertility).
Surgery can improve fertility by removing endometriosis tissue, but there is no guarantee that this will allow you to get pregnant.
Endometriosis is unlikely to put your pregnancy at risk. However, there is some evidence to show that women with endometriosis are slightly more at risk of complications during pregnancy such as pre-eclampsia, a premature birth or the need for a caesarean section.
Read information about how infertility is treated.