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McMaster University vs. transgender people

McMaster University is one of Canada’s leading research universities. From 2021 to 2024, through a funding agreement with anti-trans hate group Society for Evidence-Based Gender Medicine (SEGM), McMaster researchers collaborated with SEGM on a number of publications about trans healthcare for minors. These publications were then used as a pretext for restricting and banning trans healthcare for minors in Canada, the UK, and the US.

Background

McMaster University was founded in 1887 in Toronto, Ontario, through a bequest from Canadian Senator William McMaster. It was established as Toronto Baptist College before being renamed McMaster University in honor of its benefactor.

In 1930, the university relocated from Toronto to Hamilton, Ontario. The move was made possible through substantial financial support from the Baptist Convention of Ontario and Quebec and funding from the City of Hamilton. In 1948, the university was reorganized under the McMaster University Act, which restructured its governance and expanded its academic scope beyond its original religious affiliation. The post-World War II era brought rapid enrollment increases, particularly throughout the 1950s and 1960s, as new faculties and research programs were established.

In 1965 McMaster established the Michael G. DeGroote School of Medicine (now part of the Faculty of Health Sciences), which later gained international recognition for pioneering problem-based learning in 1969. This educational model influenced medical training worldwide.

SEGM-McMaster collaboration

In 2021, McMaster University entered into a formal research partnership with anti-trans hate group Society for Evidence-Based Gender Medicine (SEGM). Under the agreement, SEGM provided approximately $250,000 in funding to McMaster’s Department of Health Research Methods, Evidence, and Impact (HEI) to commission systematic reviews on the evidence for gender-affirming care interventions in minors and young adults.

Between 2021 and 2024, the HEI research team conducted and prepared multiple systematic reviews analyzing social transition, puberty blockers, hormone treatments, and top surgery for trans youth. These reviews were published in 2025 in peer-reviewed medical journals, reporting that only “low or very low” certainty evidence existed for many gender-affirming care outcomes.

In 2022, the Florida Department of Health’s Agency for Health Care Administration (AHCA) released a report used as a pretext for banning state coverage of trans healthcare. AHCA commissioned five reports by anti-trans activists, including a submission co-authored by SEGM-McMaster researchers Romina Brignardello-Petersen and Wojtek Wiercioch. That report was also used by Hilary Cass in the Cass Review to restrict trans healthcare for minors in the UK. The report was also cited in the 2025 Trump US HHS report created as a pretext to ban trans healthcare for minors in the US.

In 2023, SEGM held an international conference on gender medicine that featured McMaster researchers, including lead researcher Gordon Guyatt and Romina Brignardello-Petersen. In a speech at the SEGM conference, Guyatt described getting involved with SEGM:

“A colleague of mine who I highly respect, but who needs to continue to be nameless [Romina Brignardello-Petersen], because my colleague very understandably does not want to be pestered by journalists about this matter, had done a systematic review in this area. And I knew my colleague does excellent work and talked with her about it. And somehow I was contacted by somebody [Jennifer Block] from The BMJ writing about it. And because I do not share my colleague’s nervousness, I was happy to say, as I understand it, the evidence quality is very low here, and that everything that should be done about it, that should be key to any decisions that are made. That was published in a fairly prominent BMJ piece and now journalists continue to come to me — New York Times [piece by Azeen Ghorayshi], Nature, other things — where I continue to be quoted. Still not knowing almost anything about gender medicine. And indeed, with that background, if anything I say strikes you as extraordinarily naĂŻve or misguided, that probably is because it’s extraordinarily naĂŻve or misguided.” 

In sharing the report in The BMJ by anti-trans activist Jennifer Block, Guyatt stated “Current American guidelines for managing gender dysphoria in adolescents untrustworthy.”

Guyatt’s MacMaster collaborators:

In 2025, SEGM-McMaster researchers published three of the five planned systematic reviews:

Also in 2025, student activists at McMaster University began an organized campaign to get Guyatt to acknowledge that the SEGM-McMaster research partnership “utilized GRADE to lend credibility to pseudoscience that opposes gender affirming care.” In June, members confronted Guyatt and Brignardello-Petersen, who both quickly left without commenting.

The SEGM-McMaster partnership drew increasing scrutiny as more activists, faculty members, and community groups criticized the collaboration and raised concerns about SEGM’s reputation and influence on public health policy discussions. In response to this pressure, McMaster’s HEI researchers publicly stated in August 2025 that they would no longer accept funding from SEGM and that the organization initially “appeared to… be legitimately evidence-based.” They also emphasized that restricting gender-affirming care based on low-certainty evidence was “unconscionable.”

Selected SEGM-McMaster publications

Guyatt, Gordon; Brignardello-Petersen, Romina; Ibrahim, Sara; Roldán-Benitez, Yetiani; Couban, Rachel (August 14, 2025). Systematic reviews related to gender-affirming care. McMaster University https://hei.healthsci.mcmaster.ca/systematic-reviews-related-to-gender-affirming-care/

Miroshnychenko, A., Roldan, Y., Ibrahim, S., Kulatunga-Moruzi, C., Montante, S., Couban, R., Guyatt, G., & Brignardello-Petersen, R. (2025). Puberty blockers for gender dysphoria in youth: A systematic review and meta-analysis. Archives of Disease in Childhood, 110(6), 429–436. https://doi.org/10.1136/archdischild-2024-327909

Miroshnychenko, A., Roldan, Y. M., Ibrahim, S., Kulatunga-Moruzi, C., Dahlin, K., Montante, S., Couban, R., Guyatt, G., & Brignardello-Petersen, R. (2024). Mastectomy for Individuals with Gender Dysphoria Younger Than 26 Years: A Systematic Review and Meta-Analysis. Plastic & Reconstructive Surgery, 155(6), 915–923. https://doi.org/10.1097/prs.0000000000011734

Miroshnychenko, A., Ibrahim, S., Roldan, Y., Kulatunga-Moruzi, C., Montante, S., Couban, R., Guyatt, G., & Brignardello-Petersen, R. (2025). Gender affirming hormone therapy for individuals with gender dysphoria aged less than 26 years: a systematic review and meta-analysis. Archives of Disease in Childhood, 110(6), 437–445. https://doi.org/10.1136/archdischild-2024-327921

Brignardello-Petersen, Romina; Wiercioch, Wojtek (May 16, 2022). Effects of Gender Affirming Therapies in People with Gender Dysphoria: Evaluation of the Best Available Evidence. https://ahca.myflorida.com/content/download/4864/file/AHCA_GAPMS_June_2022_Attachment_C.pdf

Resources

McMaster University (mcmaster.ca)

Wikipedia (en.wikipedia.org)

Instagram (instagram.com)