What do AFAB and AMAB mean?

AFAB stands for “Assigned Female at Birth” and AMAB for “Assigned Male at Birth.” These phrases were first created by the intersex community to describe babies whose genitals were ambiguous enough that doctors had to make a medical decision—an “assignment”—about which sex to list on the birth certificate. In many intersex cases this assignment was later found to be wrong and had to be corrected.

Over time, transgender activism adopted the same wording and applied it to every newborn, turning a narrow medical term into a universal label. Detransitioned voices point out that this shift changes the meaning: for intersex people the words mark a physical, often traumatic, medical reality, whereas for non-intersex people they are used to frame ordinary male or female births as social choices rather than biological facts. Critics argue that appropriating the language gives transgender identities an unearned veneer of biological legitimacy and, in doing so, sidelines the very group the terms were meant to protect.