endoupdateblog
Transformative
Because endometriosis is a condition that is drastically under researched in relation to how common it is, there are many ‘firsts’ yet to be discovered, some of which are very overdue. Today I would like to talk about one of those very overdue firsts, a research article on endometriosis in transmasculine people.
Firstly though some people reading this may not be aware of the definition of transmasculine; a transmasculine (sometimes abbreviated to transmasc) person is someone who was assigned female at birth, but who’s gender is masculine and/or they feel more comfortable presenting themselves in a masculine way. Although transmasculine does include transgender men, it can also include (but is not limited to) people who do not permanently identify as neither male nor female, such as non-binary people.
There exists a distinct lack of research into endometriosis in the LGBT+ community and in people of colour (i'm currently working on another blog post of the subject of endo research and women of colour) . Endometriosis is a disease that does not discriminate and so nobody should be discriminated against when receiving treatment for endo. Everyone deserves the same quality of care and compassion, but delivering that care means understanding the specific needs of different groups of people.
Some opportunities have been given for trans men to speak out about their encounters with seeking treatment for endometriosis and the prejudices faced. It is undoubtedly true (and something I have witnessed personally) that many cisgender women face dismissal and discrimination when seeking treatment for endo. Yet people like trans men and black women face additional layers of discrimination simply because they are trans or black; this occurs because of false beliefs and prejudice. Removing these falsities can only be accomplished through research and advocacy, so they can receive the same level of care as everyone else.
Onto the research article then, which is titled ‘Dysmenorrhea and Endometriosis in Transgender Adolescents’, published in the Journal of Paediatric and Adolescent Gynaecology, the pre-proof was made available so the final proof article may be slightly different, but overall the results will be the same.
To start with this study enrolled 35 transmasculine people who had been diagnosed with dysmenorrhea (extremely painful periods). Below is an overview of their findings

I can see why this study chose to focus on adolescents with dysmenorrhea. Most complications with menstrual health begin during adolescence. Most women report their endometriosis symptoms beginning in adolescence, so it makes sense to investigate the onset of such symptoms in trans people too. Studies have also shown that young trans people have an increased risk of suffering from mental health conditions and that gender-affirming medical therapy and support for transitioning improves their mental health. Researching greater understanding of menstrual health in a trans context can therefore only help improve the lives of young trans people.
The issue of dysmenorrhea and endometriosis in trans men is a unique one, as some trans men opt to take testosterone. Taking low-dose testosterone for transitioning usually results in stopping periods. One study on the subject found that half of trans men taking testosterone stopped having periods by 6 months, with 93% stopping periods after a year. The fact that many of the transmasc people in the dysmenorrhea study were still getting pain and bleeding has interesting implications into the effect endometriosis has on testosterone processing in the body and is definitely worth more research.

Photo by Sharon McCutcheon from Pexels
One thing I couldn’t find much information on was the interaction between testosterone treatment and progesterone therapies. As progesterone based treatments are given to trans men taking testosterone with dysmenorrhea one would assume it was safe, but the use of hormonal treatments, particularly in adolescents has to be carefully understood to prevent any unintended harm coming to patients. For example, hormonal use for trans men and trans women is indicated to cause some alterations in bone turnover (but not bone density) in adolescents (source), the effects of adding progesterone to this are unknown.
One important thing that the study did highlight was that some transmasc people may be averse to taking hormonal contraceptives due to the perceived feminising effects of estrogen or the counteracting of testosterone. However, the authors of this study point out that estrogen levels in people taking oral contraceptive are roughly the same as those in trans people taking testosterone. The authors go on to say how evidence-based science like this can help trans people make the best decisions for their health and transitional goals.
The use of puberty blocking or masculinising hormones may alter the way in which conditions like endometriosis present. As hormones like testosterone inhibit menstruation they may also mask the presence and symptoms of endometriosis in some cases. This could lead to an under representation of endometriosis in the testosterone taking transmasc population, but could also lead some physicians to dismiss a transmasc person’s pain symptoms if they believed testosterone would prevent endo from developing.

Another important point raised in this study in terms of treatment was the consideration of unorthodox treatments for endo in trans men. In cisgender women the use of Danazol to treat endometriosis is not normally considered in modern times. Danazol was one of the first treatments developed for endometriosis, but fell out of favour due to its androgenic effects. Androgens are a class of hormones typically described as ‘male’ hormones (i.e. testosterone and androsterone). Women taking Danazol noted unwanted masculinising side effects such as hair growth and deepening of the voice, depending on the dose they received. The use of Danazol as a preferential medical therapy for endometriosis treatment in trans men is a possibility, but much more research is required before we can say for sure.
There is also the issue of surgery to consider. Some trans men may be thinking of hysterectomy and/or oophorectomy as part of their transitional journey. However, as with cisgender women hysterectomy should not be pushed on trans men as a cure for endometriosis if they do not want it, as it is not guaranteed to provide effective pain relief. For anybody with endo, regardless of gender, the most effective treatment will remain complete excision of the disease by a skilled surgeon.
Although this study was a great start for research into trans people’s medical treatment for endometriosis, it is still just the start and so there is a long way to go. This study focussed on transmasculine people, but there is still no evidence concerning the incidence of endometriosis in trans women. Transitioning hormones for trans women include some estrogen treatments - given endometriosis is an estrogen dependent disease that some scientists postulate is actually caused by exposure to estrogen (but no-one knows for sure) any instances of endometriosis should be carefully recorded in trans women.
And for anyone wondering how a endo could develop in someone without a uterus and ovaries, although rare in the extreme, endometriosis in cisgender men has been described, some of which were taking hormone therapy for prostate cancer. Interestingly this hormone therapy can take the form of typical endo therapies like Prostap and Zoladex. There are several theories as to how these men developed endo (you can read about that in the linked article), but the most likely theory is that during embryo development precursors to both sets of sex organs are present. In males the precursor to the uterus, ovaries etc (called the Mullerian duct) regresses, and the precursor to the testis etc (called the Wolffian duct) develops. Some scientists believe parts of the Mullerian duct can remain and can, if stimulated by estrogen-like hormones, develop into endometriosis. This idea has still yet to be proven, but it provides a mechanism by which endo could develop in trans women and so clinicians should be made aware.
In conclusion then endometriosis is still a puzzle that we are missing several pieces from, but by taking an inclusive attitude to our research and practice of medicine we can improve the lives of everyone who gets diagnosed with endo.