A box is checked on our birth certificate - either male or female. Yet researchers confirm there is a lot of variety in our bodies. Learn about the differences in our bodies that don’t fit within typical male and female boxes.
DeeWho is Dee?
Hi! I’m here to help you explore the subject of body parts. This is all about biological sex, which, for a long time, was thought to be pretty simple. If you’re born with a penis, you’re a boy, right? It turns out, we are as different on the inside as we are on the outside. In this section, we dig into the science behind biological sex and what it means to more than just male or female. Let’s get started…
Explore the many ways in which our bodies can differ.
When the box is checked on our birth certificate it represents many complexities. Learn about biological sex and the many unique aspects of our human bodies.
Intersex controversy and debate
Learn about the controversies surrounding the treatment of children born with an intersex condition, the regulation of intersex athletes, and even the term "intersex" itself.
The Phall-O-Meter was developed by intersex advocates to draw attention to surgeries performed on babies born with an intersex variation.
Read about variations in terminology and current debates over "intersex" vs. "DSD"
Hear from people who are intersex as they talk about their lives and identities.
Learn about the life and career of Indian runner Dutee Chand, who has challenged efforts to regulate intersex athletes.
Hear from four women who are intersex as they reflect on their lives and experiences.
Around the world
Learn about the lives of persons born intersex in other countries.
(Noun) A social construct used to classify a person as a man, woman, or some other identity and ascribe qualities of masculinity and femininity to people. Gender characteristics can change over time and vary between cultures. Learn More
(Noun) Clinically significant distress caused when a person does not identify with the sex they were believed to be at birth. Can also describe a desire to change the characteristics that are the source of the distress, such as physical anatomy. Learn More
(Adj.) Describes a person who identifies their gender as shifting within a spectrum of gender identities and expressions. A person who is gender fluid may always feel like a mix of two (or more) genders, but may feel more one gender some days, and another gender other days. Gender-fluid people may or may not also identify as transgender. Learn More
(Noun) One’s deeply held, core sense of being a man, woman, or some other gender. A gender identity can be a combination of two or more genders (such as gender fluid), and some individuals don't identify with any gender at all--described as being agender. Learn More
(Adj.) An umbrella term for variations in biological sex traits such as genitalia, hormones, reproductive anatomy or chromosomes. People are born with these variations or develop them at a young age. Learn More
(Adj.) An identity that does not conform to traditional two-sided categories of sex, gender, and sexual orientation, such as male-female, man-woman, and gay-straight. Learn More
Sex / Sex assigned at birth / Biological sex
(Noun) A person's sex (male, female, or intersex) is often determined based on the appearance of the genitalia, either in ultrasound or at birth. In reality, biological sex is more complicated, referring to a combination of anatomical, physiological, genetic, and physical attributes. These include genitalia, gonads, hormone levels, hormone receptors, chromosomes, genes, and secondary sex characteristics. The phrase "sex assigned at birth" is used by some to emphasize that genitalia alone are not always a sufficient indication of a person's sex, as well as the fact that a person's gender identity is not always aligned with the sex characteristics observed at birth. Learn More
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Citations & Sources
Ainsworth, C. (2015). Sex redefined: The idea of two sexes is simplistic. Biologists now think there is a wider spectrum than that. Nature, 518, 288-291. https://www.nature.com/news/polopoly_fs/1.16943!/menu/main/topColumns/topLeftColumn/pdf/518288a.pdf
APA Task Force on Gender Identity, Gender Variance, and Intersex Conditions (2006). Answers to your questions about individuals with intersex conditions [Pamphlet]. American Psychological Association. https://www.apa.org/topics/lgbt/intersex.pdf
Block, M. (2016, August 16). The sensitive question of intersex athletes. NPR. https://www.npr.org/sections/thetorch/2016/08/16/490236620/south-african-star-raises-sensitive-questions-about-intersex-athletes
Coleman, D. (2018, April 30). Sex, sport, and why track and field's new rules on intersex athletes are essential. New York Times. https://www.nytimes.com/2018/04/30/sports/track-gender-rules.html
Dreger, A. (2018, April 27). Track's absurd new rules for women. New York Times. https://www.nytimes.com/2018/04/27/opinion/caster-semenya-intersex-athletes.html
DSD research. (n.d.). Accord Alliance. http://www.accordalliance.org/resources/dsd-research/
Feder, E. & Karkazis, K. (2008). What’s in a name? The controversy over “Disorders of Sex Development”. The Hastings Center Report, 38(5), 33-36. http://med.stanford.edu/content/dam/sm/bioethics/documents/people/resumes/karkazispubs/Whatsinaname.pdf
Fogle, A. (2016, October 21). Falling in between: Inside the lives of intersex women. Good Housekeeping. http://www.goodhousekeeping.com/health/a40787/intersex-stories/
Gender Issues in Agriculture AGEX3003. (n.d.) Growing up intersex part 1 [Video]. YouTube. https://www.youtube.com/watch?v=I9a1rXOpIuc
Ghcorayshi, A. (2017, July 26). A landmark lawsuit about an intersex baby’s genital surgery just settled for $440,000. BuzzFeedNews. https://www.buzzfeed.com/azeenghorayshi/intersex-surgery-lawsuit-settles?utm_term=.if24OoWmp#.ot31g2...
Greenfield, C. (2014, July 8). Should we ‘fix’ intersex children? Atlantic. https://www.theatlantic.com/health/archive/2014/07/should-we-fix-intersex-children/373536/
Hartney, E. (2018, February 7). What does it mean to be intersex? Verywell Mind. https://www.verywellmind.com/what-is-intersex-21881
Padawer, R. (2016, June 28). The humiliating practice of sex-testing female athletes. New York Times Magazine. https://www.nytimes.com/2016/07/03/magazine/the-humiliating-practice-of-sex-testing-female-athletes....
Reardon, Sara. (2016). The spectrum of sex development: Eric Vilain and the intersex controversy. Nature, 533(7602), 160-163. https://www.nature.com/news/the-spectrum-of-sex-development-eric-vilain-and-the-intersex-controversy-1.19873
Ritchie, R., Reynard, J., & Lewis, T. (2008). Intersex and the Olympic Games. Journal of the Royal Society of Medicine, 101(8), 395-399. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2500237/
Sleath, E. (2014, December 2). I am intersex: Shon Klose’s story. ABC. http://www.abc.net.au/local/stories/2014/12/01/4140196.htm
Topol, S. (2017, August). Sons and daughters: The village where girls turn into boys. Harper’s Weekly. https://harpers.org/archive/2017/08/sons-and-daug
Viewpoints on DSD care. (n.d.). Accord Alliance. http://www.accordalliance.org/resources/viewpoints-on-dsd-care/
World Athletics. (2018, April 26). IAAF introduces new eligibility regulations for female classification [Press release]. https://www.iaaf.org/news/press-release/eligibility-regulations-for-female-classifica