What the study found
The article argues that sex determination does not and cannot occur at fertilization. Instead, it says sex is a complex process that occurs at various stages of human development, from the embryonic and fetal stage through adulthood.
Why the authors say this matters
The authors say the complexity of sex should guide legal definitions and related laws. They conclude that these laws must align with the evidence and with the lived experience of individuals.
What the researchers tested
The article examines scientific and medical evidence about sex determination. It also responds to a 2025 Executive Order and to state laws that restrict access to women’s and girls’ sports, bathrooms, and gender-affirming care.
What worked and what didn't
The article says its review of scientific and medical evidence supports the view that sex determination is not fixed at conception. It also challenges claims that sex can be cleanly defined as immutable at fertilization.
What to keep in mind
The abstract does not provide detailed methods, sample sizes, or specific studies reviewed. It also does not list a separate limitations section in the available summary.
Key points
- The article says sex determination does not and cannot occur at fertilization.
- It describes sex as a complex process unfolding across embryonic, fetal, and adult development.
- The authors say legal definitions and related laws should align with the evidence and lived experience of individuals.
- The article discusses a 2025 Executive Order and state laws on sports, bathrooms, and gender-affirming care.
- The abstract does not give detailed methods or a separate limitations section.
Disclosure
- Research title:
- Sex is described as a complex developmental process, not fixed at fertilization
- Authors:
- John Parsi
- Publication date:
- 2026-02-27
- OpenAlex record:
- View
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