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sex assigned at birth (SAAB)

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Sex assigned at birth (SAAB) is used to describe the categorical assignment (typically “male” or “female”) of an infant’s sex at birth. Sex is typically assigned by doctors and/or parents in order to socialize the child within conventional gender paradigms. SAAB is what appears on birth certificates. 

SAAB is generally determined based on criteria such as chromosomes, genitalia, and testosterone levels, but much variation exists that makes none of these a fully accurate or comprehensive identifier. Saying someone was “assigned female at birth” is more accurate than saying someone was “born female” or is “biologically/genetically female.” 

“Sex assigned at birth” and the related “AFAB” (assigned female at birth) and “AMAB” (assigned male at birth) recognize the individual’s lack of agency in the original decision, as well as to separate gender identity and expression from sex, and affirm the individual’s ability to determine their gender identity and expression on their own terms. Fixating on someone’s sex assigned at birth when not explicitly relevant to a story can be sexualizing and fetishizing to trans, nonbinary, and intersex people. 

Intersex people are those with reproductive or sexual anatomy (chromosome patterns, gonads, or genitals) that doesn’t seem to fit the typical binary definitions of “female” or “male.” For example, an intersex person may be born with a noticeably large clitoris, or a scrotum that is divided into two so it appears more like labia. Doctors and/or parents will often assign a sex to an intersex baby at birth, which may not be aligned with the gender identity they will have when they get older. 

While intersex is still viewed by many as a medical problem, intersex activists and supporters urge people to see it’s not. This brings up ethical questions about performing non-lifesaving medical procedures on intersex children, which often occur to make them fit the binary mold of the sex they were assigned. Intersex anatomy is naturally occurring, is often not medically problematic, and is more common than one may think. While the research isn’t robust, it’s estimated that 1-2 people out of 100 born are in the US are intersex. While many are identified as intersex at birth, some determine they’re intersex during puberty or when trying to conceive, or never at all. Terms such as “hermaphrodite” and “hermaphroditism” are unclear and generally considered outdated, though they can be used in the context of someone’s self-identification.

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Sex assigned at birth (SAAB) is a term that refers to the sex label (e.g., male or female) an infant is assigned by doctors and/or parents at birth, based on biological and genetic factors like chromosomes and sexual anatomy. SAAB is not inherently connected to gender or gender identity, and the terms are not interchangeable. SAAB is also clearer than “biological sex,” which is scientifically imprecise and can be invalidating to trans and nonbinary people.