How often does a person get testicular feminization?

Testicular feminization, also known as Androgen Insensitivity Syndrome (AIS), is a rare genetic condition where individuals with XY chromosomes develop female physical characteristics due to the body's inability to respond to androgens. It occurs in approximately 1 in 20,000 to 1 in 100,000 births. The condition is not something that a person "gets" periodically; rather, it is a congenital condition present from birth. Diagnosis typically occurs during puberty or later when secondary sexual characteristics develop.