How many intersex people are out there?
The answer to that question depends on the definition you use, but also on which research population you use. NNID uses a percentage that comes from Danish research published in 2019, based on a large random sample, that assumes the experience of having a body that does not fit within the normative social construct of male and female. The research shows that probably about 8.24 million Europeans meet NNIDs definition of intersex.
The United States (2000)
The Intersex Society of North America (ISNA) website stated long ago that in 0.15% to 0.20% of children, the genitalia give cause to seek the assistance of a medical specialist in sex determination (ISNA zd2). Fausto-Sterling, in her book Sexing the Body (Fausto-Sterling 2000), cites a rate of 1.728% in which she has included most of the diagnoses that today fall under the heading of DSD.1This rate is also cited in the article How sexually dismorphic are we by Melanie Blackless et. all. (Blackless 2000) In a response to that book, Leonard Sax assumed people whose chromosomes do not match their bodies (e.g., women with XY chromosomes) or who cannot be unambiguously classified as male or female and thus arrived at a percentage of 0.018% (Sax 2002).
Thus, the figures depend on the definitions used. For example, it is clear that Sax does not count a number of common chromosomal variations: 1 in 500 men has 47,XXY chromosomes and 1 in 2500-4000 girls has 45,X or 46,XX/46,XY chromosomes. Mayer-Rokitansky-Küster syndrome (1 in 5000 women) and micropenis (1 in 200 men) are also counted among DSDs.
The Netherlands (2014)
A percentage NNID has used for a long time is 0.5 percent. This percentage comes from the Dutch exploratory study Living with intersex/dsd published by the Social and Cultural Planning Office in 2014(Van Lisdonk 2014a). This looked at the numbers reported in medical-scientific publications for a limited number of diagnoses. It gives an impression of how many people received a specific diagnosis from doctors. It was clear from the outset that two important groups are missing from that percentage: a) those who are intersex but have never been seen by a doctor, and b) those who are intersex but have received a different diagnosis.
Denmark (2019)
In 2019, 62,675 people in Denmark were asked “Have you noticed any variations in your genitals, chromosomes, or hormones as a child, adolescent, or adult that make them not match the characteristics typical of men or women?” 1.3 percent of men and 0.9 percent of women indicated their biological sex characteristics did not fit within common definitions of male or female (Frisch 2019) 2In the same survey, 1.7% percent of this group (about 0.2% of the population) indicated that they identify themselves as ‘interkønnede’. This word is used in Northern languages in the sense of intersex, but also has the meaning of hermaphroditism and, literally, intergender. This is because both sex and gender are translated with køn in Danish. The designation interkønnede therefore has the same negative connotation as hermaphroditism or intersexuality.. This means that 1.1 percent of people fall under the definition of intersex. 3In the same survey, 6 percent of participants said they were dissatisfied with how their genitals looked. This means that approximately 8.24 million Europeans meet NNIDs definition of intersex.
Percentages in different age groups of individuals with variations in genitalia, chromosomes, or hormones such that the sex characteristics do not match those typically reported for men or women. Young people up to 34 years of age are more likely to report a variation than older people. It is unknown what causes this. (Data: Frisch et al. 2019)