Endometriosis, meeting with Lone Hummelshoj, Executive Director of the World Endometriosis Research Foundation

25 March 2022

Lone Hummelshoj, you have been an advocate for endometriosis in the past 25 years. You co-founded Endometriose Foreningen (the Danish Endometriosis Society) in 1997 and worked with politicians to change legislation and allow women with endometriosis to be treated in one of two designated national centres with specialised expertise. Denmark is the first, and only, country to offer such treatments. You are an executive director of the World Endometriosis Research Foundation that you co-founded in 2006. Its main goal is to facilitate research to improve knowledge and treatment(s).



” the average diagnostic delay tends to be around 7 or 8 years from when the woman or girl first presents to a doctor with symptoms.”

  • Could you explain to us what endometriosis is, how many women are affected and what are the consequences?

So, endometriosis is defined as tissues similar to that which grows in the uterus but is found outside of the uterus. It has been found everywhere in the body but is mainly confined to the pelvic area, where it attaches itself to the peritoneum, to the ovaries and fallopian tubes. It can also go deep down behind the uterus and affect the bowel and bladder.

Endometriosis needs oestrogen to grow. And I tend to describe it a little bit like throwing water on a rusty car. You know, the more insults, these lesions or growths are subjected to the bigger they grow. In fact, they grow quite similar to cancer. It isn’t cancer, but the way it behaves is similar to the way that cancer grows. We estimate – that’s the World Endometriosis Research Foundation – that roughly 190 million women and girls worldwide have endometriosis. That’s about one in 10, during their reproductive years.

This number is absolutely crazy, and for most of them it’ll start when they’re teenagers. It’ll start with their first period and then gradually progress into more severe disease, which is why it is so important to reduce the current diagnostic delay and get these women diagnosed and treated or managed early. We use the word manage because there isn’t a treatment that will cure the disease, but it can be managed and tempered.

The symptoms of endometriosis are painful periods or pelvic pain, when it becomes more chronic. It is also fatigue, being really really, tired. It can be painful to urinate. It can be painful to defecate. It can be heavy periods, and it is also the most common cause of infertility in women. About 1/3 of those with endometriosis will have difficulties conceiving a child, but it means that 2/3 will not. Getting endometriosis does not equal infertility.

The consequences are: women living with pain, which is never good as you would know if you’ve ever broken an arm or had had a bad headache or a migraine. Imagine having that every single day? We see quite a lot of absenteeism, with young women or girls not being able to go to school, to go out and have fun with their friends and, later, not being able to go to work every day. Endometriosis can lead to having an immensely compromised quality of life, during what should be the prime years of girls and women’s lives.

Sex can be painful so it can affect your relationships. I always feel so sorry for the young girls who may be affected by sex hurting, imagining them having to have their first experience, which should be a wonderful and lovely thing, and for that to be painful. And it might scare them off physical relationships. And that again can result in the breakup of relationships and marriages. The consequences are really bad.

It is different for the individual woman how the disease affects her, but it’s typically during their periods and, for many, also during ovulation. But then again, as I said, if that goes on for years and years, that ongoing insult or onslaught of pain can lead to a damage in the nervous system. That means that they become so sensitized to pain that they end up with chronic pelvic pain. This does not happen to everybody; just as painful sex does not happen for everybody. Just as not everybody has problems going to the toilet. It varies enormously. From, I don’t like using the word, mild, but to manageable symptoms to unmanageable symptoms.


  • How long does it take to determine if a woman has endometriosis?

At the moment, the average diagnostic delay tends to be around 7 or 8 years from when the woman or girl first presents to a doctor with symptoms. She typically has to see five or more different physicians before she gets diagnosis. So that’s not good.


  • Denmark has become the country offering the best practises for endometriosis. It came after years of fighting. Could you tell us more about this journey and how you achieved such results?

My background is in sales and marketing, with IBM, and so I’m forever a salesman. 20 years ago I called the Minister of Health and I asked for an appointment. I got one, which was really surprising to everybody. We had a meeting together with one of the Danish professors, who had taken a specific interest in endometriosis. We talked about what I just told you, the impact on quality of life, the hidden mistreatments, and we could only then hypothesize what this would cost society. Our argument to the minister was that we will save money by having treatment of endometriosis centralise and specialised, ie. designating this disease to requiring specialist care. Just like we require with cancer and many other diseases, so that they don’t have to go through a lot of hidden mistreatments, that are costly and that they don’t have to miss school and work which cost society money. And he said, what do you want? We said, we want treatment centralised and he turned around to the representatives from the National Institutes of Health and said ‘do it’. And that was it. It was me just saying “I’m going to make this happen!”


  • It is so interesting, especially because this speech about money could be replicated in many countries.

Absolutely, and since then the World Endometriosis Research Foundation ran a study called EndoCost. You can go to endometriosis.org and you’ll get all the highlights from the paper. It showed the cost of endometriosis, which is about €9000 per year per woman. So it is billions of euros.

What was interesting was that 1/3 of the costs were direct health care costs and 2/3 were due to the loss of productivity. Not necessarily absence from work but less productive at work because of pain. We have those numbers now in that study and they can be extrapolated to any country really. And I think that’s the argument, because even though everybody should care about quality of life and women and girls not being in pain, reality is that they care about what it costs society.


  • What are the different existing treatments, both in Denmark and in the rest of the world? How effective are they?

We could start with the basics, which are painkillers. What’s typically used in endometriosis is called nonsteroidals, like ibuprofen or diclofenac that treat inflammation. They, unfortunately, can be addictive. They can destroy the lining of your stomach and they inhibit ovulation. If you want to get pregnant, you shouldn’t be taking those drugs.

Then there are various hormonal treatments and they’re available pretty much in all countries in the developed world. They have the same thing in common, and that is to stop menstruation so that you don’t have that monthly insult or onslaught that exacerbates pain. That ranges from progestins, which can be titrated to different amounts, like very small amounts to higher amounts. It can go to a simple thing like the birth control pill which is taken continuously or the Mirena coil, which releases progesterone locally and is a form of contraception that prevents ovulation and having a period, to more brutal ones called GnRH analogues. The latter come in the form of agonists and antagonists, and they will put you into an artificial menopause for six months, and the side effects can be pretty bad – for some of the side effects are as bad as the disease itself. However, they work for some, and they don’t work for others. Therefore, I like to not refer to any of this as “treatment”, because it doesn’t treat the disease. Once you stop the medication, the disease will be right there and come right back. I prefer the phrase “management”, so managing the disease – tempering it – for awhile to give the girl or the woman a break from her symptoms.

The other treatment is surgery, and that’s where specialisation comes in, and that’s where it becomes incredibly important, because endometriosis really should only be undertaken by those who are specifically trained in doing endometriosis surgery. It’s highly complex. Again, comparing it to cancer surgery is what many, many do, and you would never have surgery for cancer and not go to a cancer specialist. I would urge the same for endometriosis: that you really must see somebody who does surgery regularly, because otherwise you could end up with incomplete surgery. Surgery can do damage as well. It cuts through your muscles and your nerves and if you have too many surgeries then it that in itself can contribute to additional pain. We want these women to have one really good surgery with someone who really knows how to cut the disease out.


  • Besides implementing treatments, what other policies should be taken to tackle this issue?

In terms of management, I want to go one step further as well and to talk about a more holistic approach, because each woman is individual and reacts individually to the disease and its management. I think it’s very important that she might benefit from a healthy diet. There isn’t a specific diet associated with endometriosis, it’s just a healthy, you know, a good sense of healthy diet. It won’t cure the disease, but if she has bowel issues, it might ease up on some of those symptoms. Physical therapy and exercise release endorphins that are natural painkillers. But again, if you’re in a lot of pain, you might not be able to exercise, so we have to bear that in mind as well.

What should happen from society? I really think we need to start in the schools. We need to start to educate girls and boys about what periods are and what is normal and what isn’t normal. A little bit of period pain or discomfort is probably “normal’; I think we all have that. But there’s a difference between having period pain and having pain so that you can’t go to school. You can’t socialise. If you have to take a lot of painkillers that’s not normal.

Whatever people say, pain is your body’s way of telling you that something isn’t right. I think we should be teaching girls and boys what is normal and what isn’t normal and in parallel remind primary physicians that the prevalence of endometriosis is very, very high and to perhaps have alarm bells go off, when someone presents with symptoms suggestive of the disease. If a woman goes to the doctor with period pain that is stopping her from living her life or she’s taking too many painkillers, she should get referred to a specialist so that the disease can be managed early and prevent damage to her abdomen later on and to not impair her fertility.

We should be allowed to take a day or two off every month if that is needed. If employers could allow that it would be fantastic. In fact here in the UK, Endometriosis UK, which is the national advocacy organisation, has a friendly employer scheme. Companies can sign up and say they are endometriosis friendly employers. I think that’s the only country that’s actually done that.


  • How do you explain that so many countries seem reluctant to treat endometriosis?

Endometriosis affects women. Women’s health is under prioritized in every single country in the world. In fact, it is a sad state of affairs when there is more research money given to study erection in men than there is to study pelvic pain in women. I’m afraid that’s the only answer. Women’s health is under prioritized, and this means that we do not have sufficient funding to carry out the research that will enable us to discover why endometriosis develops and how it progresses so that we can start to develop targeted treatments. We think we know that endometriosis is more than one disease, just like breast cancer is more than one disease, so one type of breast cancer may need one type of treatment, and whereas another one might need another type of treatment – it’s exactly the same for endometriosis. We just don’t know yet what these subtypes are.

As mentioned earlier, one treatment will work for some and won’t for others. But we need to find out for whom it would work and why it works. And then find other treatments for where we have nothing.

Finally, with endometriosis it is a normalization of pain that results in little investment, and as I said earlier:  pain is not normal. We have to teach everyone that pain is not normal.


  • Could you tell us more about the World Endometriosis Research Foundation, its goals, and activities?

The foundation was created back in 2006 by myself and some very passionate researchers and clinicians because we felt there was a need to standardize and harmonize the way in which we do research in endometriosis. Again, because of the very limited funding we often see very small research projects where the results are not significant, simply because there was not enough subjects involved.
If a study is carried out on 200 women, it means nothing, absolutely nothing. You need 200,000 for it to be significant. And for a disease that is as prevalent as diabetes -endometriosis is as prevalent as diabetes – we see only a fraction of comparable investment in research. We decided to develop standards, from which researchers, clinicians, scientists could collect clinical data in exactly the same way and pair that with surgical findings, as well as standardized operating procedures for how to collect biospecimens, such as saliva, urine, blood, as well as tissue samples. From the premise that if everybody does it the same way, then all of a sudden, the 200 people here and the 150 people there and the 2000 subjects somewhere else could all be compiled into one big data set and then we can start to actually really learn something about the disease.

What we’re doing is to harmonize research standards and to foster collaboration amongst centers. For this particular set of tools, we now have 51 centers around the world in 22 countries using these tools, which are available in 16 languages. That’s really started to change the way we do research because we now have more bio-specimens and clinical data that has ever been collected before in the world and that is easily comparable. We’re currently in the process of harmonizing standard operating procedures for how to deal with experimental models and endometriosis, as well as how to do imaging, and something as basic as how to perform a clinical exam.

Before we were able to do that, WERF carried out the first and only prospective study looking into the impact of the disease. It was called the Global Study of Women’s Health and, again, if you go and search on that on endometriosis.org, you’ll see the summary from that,  which documents the diagnostic delay and how pain affects women, etc. The EndoCost study I mentioned before was also carried out by WERF, because we needed those numbers in order to be able to go to governments and legislators to argue that this is a disease worth investing in.


  • Do you have any tips or advice to give to women who suffer from endometriosis?

I think one of the most important things is probably to allow yourself to have bad days. Rest if you are having a really bad day. Don’t be a superhero and stress your body more. Allow yourself to say “I am feeling terrible and I need to lie down today” and read a book or watch videos or sleep or whatever you need to do to recover. Eat healthily, and I don’t want to preach about eating because I think it’s a really difficult thing to say what you should and shouldn’t eat. I would say eat healthily 80% of the time and don’t give a damn 20% of the time. Just as we all should. I mean, this isn’t just for women with endometriosis.

There is a little bit of research. It isn’t a lot, but it makes sense that shows that Omega 3 oils are anti inflammatory. Because endometriosis is an inflammatory disease, so you have this constant inflammation going on, which is also what contributes to fatigue, things like oily fish, olive oil, nuts and seeds may be beneficial in the diet. Again, it’s just healthy eating really: cut back on sugar, but if you want a piece of chocolate then have a piece of chocolate and then don’t worry about it. Try to get a little bit of exercise if possible. Yoga, Pilates, whatever makes you feel a little bit better you should allow yourself to do. Finally, when seeking treatment and management from healthcare professionals don’t take no for an answer. Insist that you get treated by a specialist. Full stop!  Your national endometriosis support organisation may also be able to aid with that.


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