Federal Law Must Now Define 'Sex' Only by Biology at Conception: Gender Identity Not Recognized

The “Defining Male and Female Act of 2025” is a piece of legislation that, at first glance, seems straightforward: it sets hard, biological definitions for ‘sex,’ ‘male,’ and ‘female’ that the entire federal government—every agency, every rule, every regulation—must use from now on. Specifically, Section 2 mandates that Sex means a fixed, biological classification determined at conception. Male is defined as the biological sex that produces sperm, and Female as the sex that produces eggs (ova). The bill’s main purpose is to enforce a uniform, binary, biological standard across all federal interpretation.

The Fine Print: What the Government Can’t Recognize

This bill isn't just about defining terms; it’s about what the federal government is explicitly forbidden from recognizing. Section 2, under the heading “Handling ‘Gender Identity,’” states clearly that the federal government shall not recognize “gender identity” as a substitute for “sex.” They define gender identity as a “subjective, internal sense of self” that might be disconnected from biological reality. This provision is the linchpin of the bill, effectively removing federal legal recognition for gender identity across the board.

Real-World Friction: Who Feels the Change?

Because these definitions must be applied to any federal law, rule, or regulation, the impact is massive and immediate for transgender and non-binary individuals. Think about federal programs under the Department of Health and Human Services (HHS) or the Department of Education. If you are a trans man, but your federal records must now be categorized strictly as “female” based on the biological definition at conception, this could affect everything from how you access federal healthcare programs to the way your identity is recorded on official government documents like passports or social security forms. For a student relying on Title IX protections (which currently often include gender identity), the legal ground could shift entirely, potentially limiting access to facilities, sports, or protections based on their lived gender.

Administrative Headaches and Legal Chaos

For federal agencies, this bill creates a massive administrative headache. Many departments, including the Equal Employment Opportunity Commission (EEOC) and the Department of Housing and Urban Development (HUD), have spent years developing rules and guidance that integrate gender identity. This bill, with its low vagueness, forces a clear and immediate rollback of those policies. For example, if a federal contractor has been complying with an EEOC rule that protects employees based on gender identity, the contractor’s legal requirement under federal law could vanish overnight, leading to widespread confusion and litigation. The bill is clear that the government must use these definitions, but the process of unwinding decades of policy and data collection that acknowledged gender identity is not just complex—it’s a legal minefield that will likely require massive reinterpretation of existing statutes.