That’s what it feels like sometimes when dealing with endometriosis, like you’re in a boat with an oar on only one side, just paddling away but ultimately going no-where. Then hurray! Someone throws you another oar, but it’s bigger than the other one so you end up moving forward slightly but still round in circles. What you really need is an outboard motor of some kind, or maybe some sails....sorry I seem to have lost where I was going with that metaphor. Anyway, the oars in this case represent the two big conflicting ideas about where endometriosis comes from, namely retrograde menstruation and coelomic metaplasia. I’ve spoken about these conflicting notions before along with the theory of mullerianosis back in May and how there is evidence for both cases.
In one corner we have the stalwart theory of retrograde menstruation, which is generally accepted as how endometriosis comes into being, and there is evidence to support this. The fact that endometriosis bares such resemblance to normal endometrium, that endometriosis is found most frequently on the pelvic organs and experimental evidence which reported that forced surgical induction of retrograde menstruation in monkeys led to the development of endometriosis in 50% of cases.
In the other corner is coelomic metaplasia, which suggests that there are cells that already exist all throughout the body that can transform into functional endometrium given the correct stimulus. This theory best explains how endometriosis can arise in organs such as the brain and lungs and even the rare cases of endometriosis in males.
A body blow has just been dealt to retrograde menstruation in the form of a study that has just been published in the Journal of Paediatric and Adolescent Gynaecology. This study reported a case of endometriosis in a 20 year old girl who complained of serious pelvic pains. That’s nothing exceptional in itself, until you know that the girl also had Mayer-Rokitansky-Küster-Hauser syndrome, mercifully also known as MRKH. MRKH is characterised by the incomplete development of the female reproductive organs, in this case the girl did not have a uterus. Therefore, retrograde menstruation would have been impossible and cannot account for the development of her endometriosis, but coelomic metaplasia could. This round goes to coelomic metaplasia.
You’ll be glad to hear that this story has a happy ending though. The girl in question underwent electrocautery to destroy her endometriosis and was placed on oral contraceptives to reduce her symptoms, which significantly reduced her pain.
So the retrograde menstruation/coelomic metaplasia debate looks like it will have no resolve just yet. Nevermind, just keep on paddling.