| Differences of Sexual Development | |
| Intersex (atypical genitalia) | 1 in 1,500 births |
| Klinefelter’s syndrome | 1 in 1,000 births |
| Turner’s syndrome | 1 in 2,500 female births |
| Androgen-insensitivity syndrome | 1 in 13,000 births |
| 5-alpha reductase deficiency | Very rare—incidence unknown |
| People with ambiguous sexual characteristics are considered to have differences of sexual development. Listed above are the frequency estimates for some common causes of intersexuality. | |
SOURCES: GENETICS HOME REFERENCE (2008); INTERSEX SOCIETY OF NORTH AMERICA (2008); NATIONAL INSTITUTES OF HEALTH, EUNICE KENNEDY SHRIVER NATIONAL INSTITUTE OF CHILD HEALTH AND HUMAN DEVELOPMENT (N.D.). | |