Vaginal microbiota #23

Transgender women: a specific neovaginal flora

Some transgender women correct the gender incongruity of feeling like a woman in the depth of their being despite the physical presence of male genitalia and being referred to as a man by undergoing “penile inversion vaginoplasty.” In other words, by surgically transforming their penis into a vagina. However successful the surgery, the skin of this newly constructed vagina will combine skin from the penis and a skin graft from the scrotum and/or other area (s) (stomach, groin, etc.). How does this affect health? Vaginal microbiota makes a crucial contribution to good vaginal health in cisgender women.

And American researchers have now turned their attention to the intimate flora of transgender women undergoing surgery: might the composition of neovaginal microbiota explain certain problems, including the frequently reported issue of vaginal discharge? It is a question worth asking, and one that has now been answered thanks to a study comparing the vaginal microbiota of transgender women undergoing vaginoplasty with that of cisgender women. The results? They have very different microbiota. The vaginal flora of cisgender women is not very diverse and is dominated largely by lactobacilli, which creates an acidic environment that repels pathogens. That of transgender women has less than 3% of these precious allies and is much more diverse. Diversity in the vagina is not a sign of good health; quite the opposite. It is observed in cisgender women suffering from bacterial vaginosis, which increases risk of sexually transmitted infections (including HIV/AIDS) and miscarriage.

How is this new microbial ecosystem created? Or more precisely, which bacteria make up the neovaginal microbiota of transgender women having undergone surgery? They result no doubt from the flora of the skin (penis, scrotum, etc.) used during surgery. However, oral-genital and genital-genital transmission also appears to be involved. In fact, the neovaginal flora of transgender women having undergone surgery has been shown to include bacterial species typical not only of the skin and digestive tract, but also of the mouth. Since sexual relations influence the likelihood of a bacterium called E. faecalis, there is also genital transfer.

On the other hand, while the proliferation of protective lactobacilli in cisgender women can be explained by hormones, the hormonal status of transgender women (comparable to that of cisgender women due to treatment) seemed to make no difference. Further studies on larger numbers of transgender women will be needed to better understand their neovaginal health.

^{Winston McPherson G, Goldstein Z, Salipante SJ, et al. The Vaginal Microbiome of Transgender and Gender Nonbinary Individuals. Transgend Health 2024; 9: 205-11.}