Instead of a uterus, she has internal testes that never descended.

When she was 16 she had a major operation where doctors removed internal testes from her body.

Persons with PAIS-alsocalled Reifenstein syndrome-havenormal male or female form, virilized genitalia or a micropenis, internal testes, and sparse to normal androgenic hair.

According to a leaked medical report from 2009, the runner has internal testes and a condition called hyperandrogenism, which naturally increases her levels of testosterone.