‘We must break the continuing shame and embarrassment’

8.3.2022 | Roughly half of the world’s population will experience menstruation, yet we still don’t know enough about what a ‘normal’ period is. We spoke to AcademiaNet member Professor Hilary Critchley about why it’s so important that society moves past period shame and gets cracking on developing treatments for the people that suffer.
What first attracted you to reproductive medicine?
I have always been interested in endocrinology, fertility enhancement, fertility control. I think it’s absolutely fascinating how the cells in the lining of the womb respond to external signals and how exquisitely they are coordinated. Within the womb, which is so pivotal for the continuation of our species, either events happen that allow an embryo to implant and the next generation to continue, or it doesn’t happen and you get the tightly regulated event of menstruation. All of that takes place, and then everything recovers, repairs and you set off again. What other organ in the body has such clever communication?

But as someone who is a doctor by training, I want the opportunity to make a difference in people’s lives, too. So it’s about understanding the normal and understanding what goes wrong. In normal physiology, menstruation is an inflammatory event, beautifully orchestrated and essential. When menstruation goes wrong, why does it go wrong? It’s about the fundamental ability to compare physiology with pathology. Furthermore, understanding that might also have importance when we’re studying inflammation in other sites in the body.

Menstruation will affect roughly half of the human population throughout their lives. How come we’re still finding out what is normal and what isn’t?
Much of what we study still remains a highly neglected but incredibly important area. It’s a pity that change has been so slow. When I started medical school, menstruation was taboo and under-studied. It’s deeply concerning that this still remains the case decades later, and we must break the continuing shame and embarrassment when talking about periods. Even now, women find talking about periods and heavy bleeding a source of embarrassment, it affects relationships, mental health, work, yet it is so common. Heavy menstrual bleeding affects one in three women. How extraordinary that we haven’t had any new class of medical treatments for period problems and heavy bleeding for over thirty years. There’s probably no other area of medicine where the progress, in terms of targeted personalised therapies, has been so slow.

It’s interesting you mention heavy bleeding. I think many are probably unsure what even constitutes ‘heavy’, because it’s not like they have anything to compare their own situation to.
I think that’s why it was probably very helpful when the UK National Institute for Healthcare and Excellence (NICE) introduced its guidelines for heavy menstrual bleeding back in 2007 and chose a quality of life measure, rather than something quantitative. Because it is about perception, and what may be heavy for one individual may not be the same for another. That said, if your periods are heavy, you are at risk of iron deficiency and anaemia. This is also under-recognised. You can go for many years with incredibly heavy periods and not realise it. You might feel tired and dreadful from being profoundly iron deficient for a long time before recognising you’re anaemic.

In our clinical laboratory studies, we do actually measure menstrual blood loss so we know how much blood our patients are losing. Some may lose four hundred millilitres (up to 400ml) a month – that volume is equivalent to a pint of blood. In comparison, blood donors wouldn’t be allowed to give a pint of blood every month because they would feel absolutely dreadful.

Are you seeing any change at all?
Interestingly, I think we are seeing now at last an increased openness in talking about periods and menstrual problems. The apps allowing you to record your menstrual cycle might make people think, ‘well, I didn’t realise I’ve bled for so long’ or ‘I didn’t realise my period was heavy.’

Do you think that in turn will affect the science and speed up the field?
I don’t think it will move quickly, but I would like to see it moving forward. At the moment, if you think of how common it is, then research funding at least in the UK is not proportionate to the number of people the problem affects. I think lack of funding has led to inadequate advancements in the field.

If I were to look five to ten years into the future, I think if awareness was raised, there would be a better understanding of what those who menstruate expect. If we know what they might expect, then we will understand their preferences. Treatment is all about what is desired. There will be some that just want lighter and more predictable periods, because what is not liked is heaviness, embarrassment and soaking through clothes. Some may want no bleeding at all, but they want paused menstruation to be reversible.

When I started my training, many patients on the Gynaecology ward were admitted for a hysterectomy, and it’s still an option for some but we have to have non-surgical, fertility-preserving treatments, especially as many women are choosing to delay when they have a family.

But all this also has to be underpinned by really careful phenotyping of our patients. Interestingly, in many current clinical trials, we ask about heart problems, chest problems, bowel problems. Only now are trials beginning to ask reproductive cycle questions. It seems so obvious but these sorts of questions have not been asked. Now we are on the cusp of really great opportunities.

Even if a condition isn’t life-threatening, it can still be life-altering

What would you say is priority number one to focus on?
First of all, we need to talk about and recognise the problem, and there is an urgent need to change terminology. If we describe a non-cancerous disorder in the womb as benign, then it tends to be considered ‘not urgent’. Even if a condition isn’t life-threatening, it can still be life-altering. So language really matters and we need to recognise that these are chronic conditions that create morbidity.

Alongside that, we still have much to learn about the actual event of menstruation and the effect of all of other conditions, such as fibroids that we can now investigate, in large part thanks to advances in imaging. We can better image fibroids, and we can now better detect a condition known as adenomyosis, where cells from the lining of the womb bury into the muscle of the womb, which presents as heavy bleeding and pelvic pain. Underpinning all of this cannot however just be one person working in isolation, it has to be real team science.

Clearly a big but exciting job. Thanks so much for speaking to us, Professor Critchley.

  (© Emilie Steinmark / AcademiaNet /

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