Sex

Sex is a medical term used for the classification of people as "male" and "female", usually as a birth assignment based on the appearance of an infant's external genitalia. However, sex is more complicated than that. A person's sex is a combination of bodily characteristics including: chromosomes, hormones, internal and external reproductive organs, and secondary sex characteristics that develop during puberty. The common division of sex into strictly "male" and "female" ignores natural sexual variations that do not easily fit into one of the two categories, such as various intersex traits. Problematic and medically inaccurate language for sex includes phrases like "biologically [fe]male", "genetically [fe]male", or "born a [wo]man]". Such phrases over-simplify the complexities of people's biology and regard birth assignments as more important than gender identity.

Like gender, sex is not a binary term, and more like a spectrum. For instance, the term "Chimera" in genetics means that an organism or tissue has at least two different sets of DNA. (The term is derived from the creature in Greek mythology that was part lion, part goat, and part dragon.) One origin of chimerism in humans is when twin embryos merge into one embryo in utero instead of developing into separate individuals. People who are chimeras may not know they have multiple sets of DNA until they are genetically tested for a different reason. An example is a pregnant 46-year old woman who sought screening for possible genetic abnormalities. The fetus she carried had none, but her own follow-up tests revealed that her body's cells had the DNA of two individuals; parts had XX chromosomes and others had XY chromosomes.

See also

• Birth assignment
• Cisgender
• Endosex
• Gender binary
• Gender expression
• Gender identity
• Intersex
• Transgender