Suffering just a part of menstruation? Not always. Painful periods can indicate a serious underlying medical problem. It’s estimated that one in every ten women (some experts even claim it’s one in every eight) suffers from endometriosis. This condition is also a cause of female infertility. In 40% of women with fertility problems, it’s caused by endometriosis.

Endometriosis is a chronic condition where tissue that looks like that which lines the inside of the womb (endometrium), grows outside the uterus. These places with endometrial cells are called patches. Most often these patches are found on the ovaries, fallopian tubes and outer surface of the uterus. Depending on their location, the patches of endometriosis can cause infections and lead to all kinds of complaints. In very rare cases the growth can expand to Deep Infiltrating Endometriosis (DIE), where the patches are also found outside the abdominal cavity, for example in the chest.

Severe period pain – so bad that you can’t function normally for one or two days a month – is the most common symptom of endometriosis. Other symptoms include feeling bloated, fatigue, heavy menstrual bleeding, chronic pain in your lower belly, pain during sexual intercourse, pain during ovulation, pain in the premenstrual phase, painful bowel movements and pain when urinating during your period. But, to make it extra complicated, it’s also possible to have endometriosis without any of these complaints. In the UK, around 1.5 million women are living with endometriosis.

Severe period pain – so bad you can’t function normally for one or two days a month – is the most common symptom of endometriosis

It’s still unclear what exactly causes endometriosis. There are many possible theories, the most famous one blaming retrograde menstruation. That’s when menstrual blood flows the wrong way: backwards up the fallopian tubes and into the abdomen. However, this theory has already been proven wrong in 1992. Around 90% of women occasionally menstruates retrograde, but nowhere near all these women suffer from endometriosis.

Another explanation is that embryonic cells have been left in the abdominal cavity and this tissue leads to problems later in life. Also immunodeficiency disorders or environmental factors such as environmental pollution are thought to be a possible cause. Although the responsible gene hasn’t been found yet, there’s a big chance that hereditary factors play a role, as the disease is more common in some families than in others. More research into what causes this condition is necessary.

Unlike it’s usually explained, endometriosis patches aren’t the same as uterus tissue. The tissue looks like that which lines the inside of the uterus (the endometrium), but the differences are clearly visible under a microscope. The endometriosis cells, however, do react in a similar way to womb tissue. Influenced by female hormones during the menstrual cycle, they grow, break down and bleed. This internal bleeding can lead to pain, irritation, inflammation and scar tissue forming.

Not menstruating anymore, for example after the menopause or after a hysterectomy, doesn’t automatically mean that the problem is solved

Endometriosis is most common in women during their reproductive years, but patches have also been found in young children, fetuses and even in men. Not menstruating anymore, for example after the menopause or after a hysterectomy, therefore doesn’t automatically mean that the problem is solved. Endometrial cysts, scar tissue and adhesions on or around organs don’t just disappear. They can keep causing problems.

Endometriosis affects each woman differently. That’s why a personal treatment plan is needed. What works for one woman, doesn’t do anything for the other. Unfortunately, the ideal solution hasn’t been found yet. Some go for pain management, others opt for hormones which stop the menstrual cycle and thus also stop the reactions of the endometriosis patches. The trouble is that many treatment options lead to a (temporarily) reduced fertility.

Endometriosis patches can be removed by a specialist gyneacologist, through laparoscopic surgery. This takes a lot of experience and knowledge of the disease. A hysterectomy could be a possible solution for adenomyosis (endometriosis interna); a condition in which the patches have grown into the muscular wall of the uterus, causing it to enlarge.

Often, endometriosis is mistaken for something else, such as ‘normal’ period pain or a urinary tract infection

A small glimmer of hope: there’s more attention for endometriosis. Since 2008 there’s a European Guideline on the Management of Endometriosis, with recommendations and treatment options. This guideline is updated regularly. In February (2022), the European Society of Human Reproduction and Embryology (ESHRE) published new clinical guidelines for the diagnosis and treatment of endometriosis. The not so good news: it still takes way too long before endometriosis is diagnosed; on average between seven and eight years. Often, it’s mistaken for something else, such as ‘normal’ period pain or a urinary tract infection. That’s why it’s key to distinguish between ‘normal’ and ‘abnormal’ menstrual complaints.

Think you might suffer from endometriosis? Make an appointment with your GP, or rather go to a specialist gyneacologist. It might also help to get in touch with fellow-sufferers. Endometriosis UK provides support services, information and a community for those affected by endometriosis (check out their local support groups). In the USA, that’s done by the Endometriosis Association. Living in a different country? On endometriosis.org you’ll find a list of non-profit endometriosis organisations around the world and their support groups.

Also good to know: in France president Macron has launched a national strategy to combat endometriosis. What’s next?

Period! is an independent, online magazine about all aspects of menstruation. Period! is not intended as a substitute for medical advice. If you’re suffering from medical complaints, always visit your doctor or GP. Editorial articles can contain affiliate links. Sponsored collaborations can be found in the category Spotlight. Do you have any questions? Check our Contact page.

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