For biomedical journal policy, the US sex-binary reporting mandate began as an executive order and became an editorial workflow problem. On January 20, 2025, Executive Order 14168, titled "Defending Women from Gender Ideology Extremism and Restoring Biological Truth to the Federal Government," defined sex as an individual's immutable biological classification as either male or female. It directed federal agencies to remove statements and materials that promote what the order calls gender ideology. Through 2025 and into 2026, the order's language moved through federal grant systems, agency data standards, and, eventually, journal instructions. The journals were not ordered to change. Their authors, and the data those authors are permitted to report, were.
That distinction matters. A federal mandate can bind a grantee without binding a publisher, yet the publisher receives what the grantee is allowed to submit. Many biomedical journals had spent years asking authors to report sex and gender as separate constructs. The Sex and Gender Equity in Research (SAGER) guidelines, developed by the European Association of Science Editors, recommend reporting sex and gender when relevant, including the method of measurement. The International Committee of Medical Journal Editors (ICMJE) recommendations push authors to describe how sex and gender were considered in study design and analysis. The new federal language cuts against that tradition. It asks for binary sex and, in many agency contexts, removes gender identity as a distinct reporting category.
What changed at federal agencies
At the National Institutes of Health, the Sex as a Biological Variable policy has required applicants since 2016 to explain how sex is considered in vertebrate animal and human studies. The 2025 shift was not the introduction of sex as a variable but the narrowing of how sex is defined and the removal of gender-related terminology from many agency documents. Grant reviewers, institutional signatories, and data safety monitors began seeing forms with only male and female options where some had previously allowed sex assigned at birth or additional categories. The NIH Sex as a Biological Variable guidance now carries the executive order's binary definition into application materials.
At the Department of Health and Human Services, the same language appeared in guidance and public documents through 2025. Researchers who had built questionnaires with separate sex and gender fields found that the federal export format no longer included the gender identity variable. That is the first concrete consequence most study teams noticed. It was not a journal policy change. It was a data dictionary change that made the journal policy change inevitable.
How journals are responding
Editorial policy revisions are happening unevenly, and the pattern follows funding more than geography. Journals with a large share of NIH-funded submissions are moving fastest. Some have replaced "sex assigned at birth" with "sex (male or female)" in their author guidelines. Others have kept a free-text field and added a note that US federally funded submissions must follow sponsor definitions. A smaller number of editors have inserted the sponsor language into the submission checklist while leaving the research reporting policy intact.
- Rewording the sex field from "sex assigned at birth" to "sex (male or female)."
- Adding a jurisdiction note for US federally funded submissions.
- Moving gender identity variables to supplementary files where sponsors permit.
- Updating manuscript management system instructions for editors and reviewers.
That fork is rooted in the older Sex and Gender Equity in Research (SAGER) guidelines, which call for reporting both sex and gender when relevant. Journals that adopted SAGER now have to decide whether the federal definition overrides a guideline they chose for scientific, not legal, reasons.
The implementation gap on campus
The change on a policy page is clean. The change in a research office is not. At a US academic medical center, an institutional review board protocol may ask for sex assigned at birth, while the case report form has been built with male and female only because the electronic data capture vendor imported the federal standard. The federal progress report may then require the binary field to match the final dataset. A coordinator has to reconcile those documents, often by building two fields and exporting one. That duplication is not harmless. It creates a second version of the same variable, and the second version is the one that reaches the sponsor and then the journal.
The international split
Outside the United States, the legal pressure disappears but the editorial pressure does not. The ICMJE recommendations still treat sex and gender as separate aspects of study design that require precise reporting. A journal in Berlin or Melbourne does not have to adopt a US executive order, and many have not. What changes instead is the layer beneath the policy: instructions for US authors get an added sponsor clause, rules about supplementary data are split by funding source, and revision letters now have to explain why a gender analysis is missing. That smaller shift is less visible, but it is the one working scientists experience every submission cycle.
Who gets left behind
The sharper cost lands on studies of people whose sex or gender does not fit a binary category. A researcher studying cardiovascular risk in transgender adults may need to describe baseline sex without erasing the population the study exists to understand. The journal can still publish the analysis. The federal dataset behind it may not contain the categories required to describe it. That is a measurement problem, not a wording problem. When a category is removed from a dataset, it can disappear from the published record, and later from the evidence base that clinical guidelines rely on. The full text of Executive Order 14168 shows how deliberately the definitions were narrowed. The consequences in journals are still uneven because the categories available in submitted datasets are uneven.
For university research administrators, the immediate task is smaller and more procedural. Update consent forms so they distinguish what is collected for local clinical care from what is reported to the federal sponsor. Check the export map between the electronic data capture system and the grant progress report. Put a note in the lab manual about which variable feeds which system. The earlier guidance on NIH and NSF banned terminology explains how agency language changed during 2025, and the same compliance logic now reaches journal submissions.
The year two question
By 2026, the first wave of journal policy revisions has done what first waves usually do: it has clarified some fields and exposed others. Some editors now ask for sex as male or female only. Some ask for both sex and gender when the data allow. Most are choosing a middle path that depends on sponsor, country, and manuscript type. That variability is inconvenient, but it is not the deepest problem. The deep problem is whether the datasets authors submit still contain the variables needed to answer the research questions the papers claim to address. Editors can rewrite an author guideline in a day. They cannot restore a category that was never collected, or a variable that was stripped in the sponsor's export format.
That is the question year two will force: not whether journals can comply with a binary sex definition, but whether the published record will remain detailed enough for readers to know who was studied and who was left out.
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