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Important but Under-Recognized: What Is Endometriosis?

Endometriosis is a common condition that affects about 190 million people worldwide. As of today, the condition is very difficult to diagnose and treat. Why so? Krina Zondervan - Co-Director of the Endometriosis CaRe centre in Oxford - sheds light on this important question. 

Why does endometriosis deserve our attention?

Endometriosis is a common condition that affects about 190 million people worldwide.

This is a condition where cells and tissue that normally line the uterus, called the endometrium, end up somewhere else in the pelvis. 

With every period, these bits of tissue respond to hormones, and they bleed like your normal endometrium would do, and that creates problems. These small bits of disease essentially create wounds. 

One of the key symptoms of endometriosis is pelvic pain, especially during periods, but also pain during sex or pain at other times during the menstrual cycle. 

I think endometriosis is a really important condition because it's very under-recognized. 

One of the reasons could be that these types of pain, that are associated with periods, are not necessarily something that women like to talk about; there might be a stigma around that. Although we're working on making it a topic that is more acceptable to talk about, I think for a lot of women that is still difficult. 

The other element is that a lot of doctors do find it very difficult to diagnose endometriosis. These types of symptoms that I’ve described — pain during periods, for example — do not necessarily mean that a woman has endometriosis. It could be caused by other conditions. 

So, endometriosis remains very difficult to diagnose and also treat. That's why, given that it's such a common problem, we really need to devote more attention to it.

What are the origins of endometriosis?

One of the main theories is that during periods some of the endometrium is shed, and some of that endometrium — rather than with the blood coming out of the vagina — could go up the fallopian tubes and end up in the abdominal cavity (retrograde menstruation). It is pretty well established that this is a process that happens in most women to a certain extent, but in women with endometriosis, some of the cells that are in that menstrual blood manage to stick to surfaces within the abdomen, within the pelvis. And we don't really know why that is so. 

We do think that most endometriosis probably originates from this process during periods. 

There are also some other theories. One of them is that cells within the pelvis can change to a cell type that is similar to the endometrium. We call that metaplasia. But that's likely to be a rare occurrence. There are examples of cases where we think that this might be happening, e.g., there are very rare cases of endometriosis in men who have had hormone treatment and clearly — as they don’t have periods — there will be reasons other than retrograde menstruation for this. But those instances are extremely rare. 

We think that this process called retrograde menstruation is the main origin of endometriosis. But there are lots of factors in women who do develop endometriosis that predispose them to those endometrial cells being able to stick and cause problems.

What are the symptoms of endometriosis? You've mentioned pain, and talking about the pain, how can a woman tell that this pain is not related to periods but deserves special attention from a health care provider?

That is very difficult to know. 

I think one of the first things to say is that pain that really is so bad, that really affects your daily life, is something that should be checked out, whether it's going to be endometriosis or something else. 

One of the reasons could be that these types of pain, that are associated with periods, are not necessarily something that women like to talk about; there might be a stigma around that. Although we're working on making it a topic that is more acceptable to talk about, I think for a lot of women that is still difficult.

Particularly period pain, but also pain during sex, or pain at other times that is so bad that you have to take painkillers to really get through the day, or it affects you some other way. That's not normal, and that's why you should have that checked out. 

As I said, that may not be endometriosis, but that needs to be investigated, and it is something that women should be aware of. These are not symptoms that should simply be ignored or put up with, which is what a lot of women over the decades and centuries have done. 

Could you please go through some other symptoms of the disease?

1. Pain is the main one. 

2. Often with pain come symptoms like real tiredness. Tiredness is often associated with pain. 

3. The other issue that some women may face is that they have problems conceiving, problems getting pregnant. That's not the case with all women. There are a lot of women out there who have been diagnosed with endometriosis and have been suggested “you should try getting pregnant soon because you might have a problem” and then they get pregnant very quickly, but other women may struggle for many years. 

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