Organisation Intersex International

Health and Science Resources

Introduction to Biosex variations

List of articles follows this chart

How common is intersex? (Please see note below)

Not XX and not XY                                                                                                      

Klinefelter (XXY)                                                                                                         

Androgen insensitivity syndrome                                                                             

Partial androgen insensitivity syndrome                                                                

Classical congenital adrenal hyperplasia                                                           

Late onset adrenal hyperplasia                                                                             

Vaginal agenesis                                                                                                  

Ovotestes                                                                                                                 

Idiopathic (no discernable medical cause)                                                            

Iatrogenic (caused by medical treatment,

for instance progestin administered to pregnant mother)                                     

5 alpha reductase deficiency                                                                                

Mixed gonadal dysgenesis                                                                                    

Complete gonadal dysgenesis                                                                             

Hypospadias (urethral opening in perineum or along penile shaft)                           

Hypospadias (urethral opening between corona and tip of glans penis)         

Total number of people whose bodies differ from standard male or female                       1 in 100 births

Total number of people receiving surgery to "normalize" genital appearance                    1 or 2 in 1,000 births

Source: Blackless, Melanie, Anthony Charuvastra, Amanda Derryck, Anne Fausto-Sterling, Karl Lauzanne, and  Ellen Lee. 2000. How sexually dimorphic are we? Review and synthesis. American Journal of Human Biology  12:151-166.

Please note:  The new term, "Disorders of Sex Development" which OII rejects for many different reasons, includes  a whole host of intersex variations which were never considered intersex before but which OII has always included  as intersex, since OII's definition of intersex is anyone born with a body which is not standard female or standard  male according to the norms arbitrarily sanctioned by medical and legal institutions throughout the world.  Thus the  numbers listed in the chart above would be extremely low if one were counting all the people born with what doctors are now calling a "DSD".

• OII's Official Position on Health Care
  

• Ten Misconceptions about intersexuality
  

• Mutilations or non-consensual normalization treatments?
  

• A message of healing and hope: a holistic, person-centered approach to intersex health
  

• Handbook for Parents written by Parents
  

• Intersex – Medical Perspective
  

• Typical criteria of sex
  

• What's In a Karyotype?
  

Articles By Dr. Milton Diamond

• Articles by Dr. Milton Diamond et al. (list of several articles available online)
  

• The Right to Be Wrong
  

• MANAGEMENT of INTERSEXUALITY: Guidelines for dealing with individuals with ambiguous genitalia.
  

• Pediatric Ethics and the Surgical Assignment of Sex
  

• PEDIATRIC MANAGEMENT OF AMBIGUOUS AND TRAUMATIZED GENITALIA*
  

• Sex Reassignment at Birth: A Long Term Review and Clinical Implications
  

• The John/Joan Case: Another perspective
  

• Sex and Gender: Same or Different?
  

• Sexual Identity and Gender Identity are Different
  

• Androgen insensitivity syndrome and Klinefelter’s syndrome: sex and gender considerations
  

For more articles available online:  Click here

1 in 1,666 births

1 in 1,000 births

1 in 13,000 births

1 in 130,000 births

1 in 13,000 births

1 in 66 individuals

1 in 6,000 births

1 in 83,000 births

1 in 110,000 births

no estimate

no estimate

no estimate

1 in 150,000 births

1 in 2,000 births

1 in 770 births