It’s an increasingly busy time for endometriosis research at the moment. In the last 31 days there have been 111 articles published on endometriosis, which means an average of just over 3 articles every day. That’s also pretty impressive when you consider that, in the same period of time ten years ago, there were only 33 articles published! So the march of progress rolls ever onward and it’s nice to know endometriosis isn’t being left behind; however this means it’s becoming harder for me to keep up with the research! I shouldn’t complain really, so instead I’ll get on with a roundup of this month’s top endo research highlights.
I’ll start off with what, at first glance, would appear to be a report from the Twilight Zone. It’s another report of endometriosis occurring in a man. I say ‘another’ as if it happens all the time, but this is only the fifth or so record of endo in a man, ever. I’ve reported on endometriosis in males before and it is a very unusual thing to find for several, probably quite obvious reasons. However, previously reported cases have been in elderly men undergoing estrogen therapy for prostate cancer. The thought behind this was that the estrogen somehow caused certain cells in the male body to transform into endometrial cells. This new report throws a bit of a spanner into the works. If you click on the above link you should be able to read the full article, but basically a man was admitted to hospital with an inguinal hernia (a hernia located just above the testicles, in line with the bladder). Upon surgical inspection a cyst was discovered that was found to have endometriosis within in it. The really puzzling part here is that the man was undergoing anti-estrogen therapy for infertility, so how could the endometriosis possibly have developed? It makes no sense.
|Seriously, this picture makes more sense|
The authors of the paper point out that there are three main theories about how endometriosis develops; transplantation (aka retrograde menstruation), metaplasia and embryonic rest. Transplantation can be discounted straight away; metaplasia could make some sense as it relies on the transformation of tissue under the influence of inflammation or hormones, but the man was taking anti-estrogen medication so that doesn’t quite hold. That leaves embryonic rest theory. This basically states that, during development, microscopic pieces of the tubes which go on to form the reproductive organs end up getting misplaced around the body. These tiny pieces can then go on to develop into what we see as endometriosis. If this was to happen in a man, we would expect to see endometriosis developing along the ejaculatory and diferent ducts, which is exactly what the authors found, so it looks like we have a winner for embryonic rest theory.
Next up is study on the effects of different causes of infertility on the outcome of IVF/ICSI. Many women with endometriosis also present with subfertility or infertility, therefore a higher number of women with endo are likely to employ assisted reproduction technologies (ART) if they cannot conceive naturally. This may lead some women to wonder if all the problems endo causes will have any impact on the health of their baby. This study aims to answer those questions by taking patient records from 255 Finnish women (29 of whom were diagnosed with endometriosis) that had undergone successful assisted reproduction of some variety and comparing them to women who conceived naturally.
What they found was that women with endometriosis who underwent ART were at the highest risk of pre-term birth and thus, were more likely to have babies of low birth weight. However, though this may sound scary, the authors also found that these babies required an amount of neonatal care similar to that of all the other subgroups of women, indicating that though the babies were small, they were also healthy. Interestingly, although this was a relatively small study, it found that women with endo who conceived with ART were less likely to have a previous miscarriage, a chronically ill baby or foetal demise than healthy women who conceived naturally. So if you do have endometriosis and are considering IVF or another type of ART, hopefully this study will put your mind at rest a bit. If you would like to read the full article, you can by following this link.
Moving on now to a couple of studies from our Teutonic cousins; the first of which looks at the age distribution of women with endometriosis. This study took information from 42,079 women who were diagnosed with endometriosis in Germany between 2005 and 2006 and divided them into three age groups; premenopausal (0-45 years), perimenopausal (45-55 years) and postmenopausal (55-95 years). What they found was that the majority of women with endo were in the premenopausal group (33,814 or 80.36%). That doesn’t come as much of a surprise as it’s the largest age group and the one we most commonly find women with endo in. What was quite surprising was the finding that 7,191 (17.09%) women with endo were in the perimenopausal group and 1,074 (2.55%) were in the postmenopausal group; which means nearly 1 in 20 women diagnosed with endo were over 45. This shows that endometriosis does not discriminate by age and that it is important for medical professionals to know that just because your periods have stopped, it doesn’t necessarily mean your endo has.
The second study from Germany examined the cost of endometriosis in terms of in-patient treatment in 2006. Coincidentally this follows on nicely from the previously study which was looking at number of women diagnosed and this one looks at the cost of treating those women. These authors found that a total of 20,835 women were admitted to hospital for endo treatment in 2006 at an average cost of 3,056.21€ each. In total this brings the cost of treating all those endo patients to 40,708,716.26€. That’s just in-patients treatment as well, it doesn’t take into consideration the addition cost of lost work productivity, out-patient costs, or other economic factors that endo impacts on. It wasn’t long ago that I posted about a study that examined the total cost of endo, and if 40 million Euros sounds like a large amount of money, the true cost is likely to be 10 fold.
The final study for this month seems a little controversial to me. Not because there is anything particularly offensive or contentious said, but the conclusions that are drawn are tenuous to my eye. You can read the summary here and make up your own mind, but I’ll tell you what I think. To summarise, the authors of this study conclude that endometriosis is rare in rural, isolated communities such as those in Northern Uganda, because the women there have a high number of children, have more teen pregnancies and a longer duration of breast feeding. An interesting conclusion but I can see several flaws in it. Firstly, I’m not sure I agree wholeheartedly with the opening statement “Women in Western nations are exposed to an "unnatural" high number of menstrual cycles”. Maybe it’s just the way it’s worded, but I don’t like that sentence. I can see where they are coming from; women in Western countries start their periods earlier and have fewer children than those in developing countries. But how is this ‘unnatural’? What is a 'natural' amount of menstrual cycles? Is there such a thing?
Also it doesn’t seem to take into account that women in developed countries have a far greater use of the contraceptive pill, which means fewer, lighter periods. For example, in the UK in 2008, 84% of women of reproductive age were taking the contraceptive pill; compare this to only 15% of women of the same age group in Nigeria (Source: Worldbank, I couldn’t find the stats for Uganda). So surely this indicates that saying women in the Western world have an ‘unnaturally’ high number of menstrual cycles, isn’t necessarily correct.
Another thing that’s bugging me is that, out of the 528 gynaecological consultancies performed over a year at the Ugandan Aber district hospital, only 1 woman was diagnosed with endometriosis thus, the authors conclude, it is rare in this part of the world. However, even in wealthy western countries, there is a very high rate of misdiagnosis and endometriosis specialists who can accurately and thoroughly diagnose the disease are in short supply; so how can you expect the same level of diagnostic accuracy in small rural hospital in a developing nation with no specialist training? It is very likely endometriosis is far more common than reported here, but inadequate facilities and ‘masking’ of the disease by high pregnancy rates leads to under-reporting of endometriosis in this part of the world.
|Pictured: The developing and developed world; sadly the one on the right is only marginally better at diagnosing endo than the one on the left|
One last thing is that it’s assumed that number of menstrual cycles (and hence menstruation itself) is important for the development of endometriosis. Whilst there is still some debate about this, consider the fact I have reported (in this post and previously) on cases of male endometriosis, endometriosis in unborn foetuses, endometriosis in women who can’t menstruate and even endometriosis in animals that can’t menstruate. So I’ll leave you to think about how relevant menstruation may be in the development of endometriosis.