This article aims to contribute to a better understanding of the experience of hormone therapy with testosterone as perceived by trans people.

An analysis of video blogs on YouTube for and by transmasculine individuals during their first year of hormone therapy with testosterone was conducted. A total of 63 video blogs from five YouTube channels of North American trans men and one non-binary person taking testosterone were analyzed.

The transmasculine people's video blogs discuss how people experienced testosterone on a daily basis, how they negotiated their expectations and lived the impacts of their hormone therapy. The results identified the elements to be taken into account in accompanying the transition with testosterone, both bodily and symbolic, and reflected the multifaceted nature of the subjective experience of testosterone. They showed that changes are envisioned according to three levels of expectation: highly hoped for, neutrally expected and dreaded. Among these, voice seems to be the most important change, followed by the disappearance of menstruation and the appearance of hairiness.

This methodological research underscores the importance and uniqueness of educating and training trans and non-binary people through online resources for and by peers. It also highlights the very active and unique experience of gender transitioning and the investment of their trans male bodies which are not copies of cisgender men but new constructions of the body. The knowledge produced and consumed by transmasculine people on the Internet must be recognized for their complementary contribution to the medical literature, as they provide new expert knowledge on transition with testosterone used by transmasculine people.