From the point of view of a large part of the medical profession, intersexuality is - judging by the unquestioned norm of the male and female body - a so-called Disorder of Sex Development (DSD), which must be "corrected" in early childhood by means of genital plastic surgery and hormone treatments.
Intersex rights organizations defend against this practice of medical pathologization, standardization and paternalism.
They protest against cosmetic operations that are carried out in childhood (and in some cases later) without the informed consent of those affected.
A significant number of intersex people have had traumatic experiences with such operations, which they see as mutilation and a violation of human rights.
In order to illustrate the grave injustice through the injuries suffered, some invoke a comparison with National Socialist crimes and claim that childhood genital corrections were perfected under National Socialism and have been carried out systematically ever since.
However, a blanket comparison relativizes the industrial-scale, bureaucratic extermination of the Jewish population, the mass murders of Sinti and Roma as well as of individuals with physical disabilities.
It also needs to be asked whether there is any historically verifiable evidence for statements such as that intersex people born before 1945 were "almost always victims of the racial hygiene of National Socialism", unless hidden by their families .
In fact, there is a lack of serious historical research to verify these assumptions, as the research focus has thus far been mostly on medical publications.
The aim of this article is to summarize the results of this scarce research and to point out the enormous need for research .
The practices of gender normalization and pathologisation, medical paternalism, social exclusion and discrimination of intersex people are not NS-specific but deeply rooted historically.
The same applies to the eugenic problematisation of gender ambiguity, which began in the 19th century and intensified at the beginning of the 20th century in the course of the establishment of so-called racial hygiene: doctors identified it as a biological danger to the healthy Racial Corpus ("Volkskörper").
This representation intensified with the beginning of the National Socialist rule.
Many Nazi physicians based themselves on the genetic theory of intersex conditions of the Jewish biologist Richard Goldschmidt, who from 1915 onwards developed a theory of the genetic determination of sex.
According to this theory, the intermediate forms of sex should also depend on the quantitative balance of genetic determinants of masculinity and femininity.
As proof he used cross-breeding experiments with local populations of a moth species he called breeds.
Medical doctors adopted Goldschmidt's theory to support their claim that so-called racial mixtures are also responsible for the occurrence of intersex conditions in humans .
They used the theory of intersex conditions as an explanation for all phenomena that deviate from gender and sexuality norms - from homosexuals and very hairy women to so-called real hermaphrodites.
The eugenicists concentrated primarily on those with only minor apparent deviations, because their number was regarded as alarmingly large.
Especially for this group, the term intersex constitution (or intersex), which was introduced in 1924, prevailed .
In contrast, people with conspicuous ambiguity of the genitals were usually called "hermaphrodites".
Some physicians regarded the intersex constitution as a cause of political loss of instinct, which manifested itself in "Marxism and Bolshevism" or "female emancipation"; intersex was also said to occur more frequently among "Jewish men and women" .
Various doctors expressed concern that while people with an intersex constitution had good chances of getting married, their marriages would remain childless or even lead to "low-grade" children.
In the interest of a strong and healthy population, intersex persons should therefore be prevented from getting married .
Pseudo- and true hermaphrodites, on the other hand, were considered by most doctors to be infertile. Nevertheless, a relevant dictionary warned against this:
"Especially if there is a suspicion that there is still the possibility of procreation, marriages should be strictly forbidden, because these deformities can also be inherited. [...] Serious consideration should be given to sterilizing individuals with malformations of the external genitals as a matter of principle." 
In a German magazine for the entire judicial medicine it was also stated that:
"In our German conception, it is probably a serious hereditary physical deformity. At most, a marriage would be considered with a hereditary defective or infertile person." 
The fact that the latter option was actually implemented is confirmed by the case of a person who, on the basis of the diagnosis of "male pseudohermaphroditism", was allowed to change the official sex entry to male and was subsequently allowed to marry an infertile woman .
But apart from such special cases, the public health department refused a marriage suitability certificate ("Ehetauglichkeitszeugnis") in cases of severe hereditary disease and applied for forced sterilisation.
However, there was no uniform medical opinion on the hereditability of the various phenomena that were grouped under the term hermaphroditism.
In 1936, Otmar Freiherr von Verschuer, a leading racial hygienist of the Nazi regime, stated in the journal Der Erbarzt that hereditary conditions were probable in some cases, but not certain.
He spoke out against a general forced sterilization of "hermaphrodites" and referred to the necessity of individual case examinations. In a case of a father of two children with pseudohermaphroditism masculinus, who had also fathered three "clinically completely healthy" children, Verschuer rejected sterilization because the man was "not hereditary in the sense of the law" .
Ultimately, however, the case-by-case hereditary health assessment led to a massive dependence on the experts and posed a real threat to intersex persons to become victims of eugenic coercive measures.
Were genital corrections performed on intersex children in the Nazi state on a systematic basis?
The medical publications do not offer any evidence for this.
An article published in 1934 in Zeitschrift für Geburtshilfe und Gynäkologie by the gynaecologist Hans Christian Naujoks summarizes the discussion of the medical profession during the Weimar period and endorsed the recommendation,
"to initially refuse all operations in such cases and wait to see how the further development of the child will be [...]. The psyche, the approach towards gender, the choice of the individual is the most important detereminant in our therapeutic actions. 
Since the self-perception of sex is not clear until puberty, an official sex change should not be carried out before this age.
While there are no specific treatment recommendations for children in the rest of the literature, there was broad agreement that the psychological sex of adults was decisive .
The handbook of forensic medicine and scientific criminalistics ("Handwörterbuch der gerichtlichen Medizin und naturwissenschaftlichen Kriminalistik") stated:
"In non-forensic cases it is recommended that adult hermaphrodites remain in the sex they themselves consider to be the more suitable for themselves" .
Even convinced supporters of Nazi population policy such as Naujoks were of the opinion that elective cosmetic genital surgery was an "aid to the individual".
In the "interest of the people", however, they rejected surgical or hormonal "measures to promote fertility" for hermaphrodites, because
"the intrinsic value of this offspring appears questionable" .
It is questionable to what extent such recommendations have been implemented in practice. Naujoks reported on two "hermaphrodites" for whom he had followed their individual ideas regarding genital surgery or gender reassignment .
In two patients, whose male gender seemed to be beyond doubt, a uterus and inguinal testicles were discovered during the surgical treatment of an inguinal hernia; the doctors kept their diagnosis of hermaphroditism secret from their patients in order not to confuse them in their self-image as men.
In one of the two cases the uterus and inguinal testicles were left in place, in the other removed . The published case reports do not allow the conclusion that doctors have generally performed forced treatment.
With regard to intersex children, the situation is less consistent: in two cases where gonads were found that contradicted the sex registered at birth, doctors refrained from genital corrections and forced sex reassignment .
In the case of a thirteen-year-old girl whose psyche was allegedly clearly female, the well-known Berlin gynaecologist Walther Stoeckel ordered the surgical removal of the "enlarged clitoris".
It cannot be ruled out that he decided over the heads of the adolescents . A publication from 1948 provides retrospective insight into two other fates from the Nazi era: In a child who had been raised as a girl until then, the sex was changed at the age of six years, followed by multiple operations to treat hypospadia were operated on several times - that is, the urethra, which emerges at the underside or root of the organ classified as the penis, was moved to the tip.
The second case concerned a two-year-old child diagnosed as female pseudohermaphroditism, in which - at the mother's instigation - the "enlarged clitoris" was surgically removed. In 1944 the child's uterus was also removed for eugenic reasons . This provides evidence that in the Nazi state, genital plastic surgery was indeed carried out on intersex children in isolated cases.
However, it cannot be deduced from the sources known to date that this was done systematically. If, on the other hand, hypospadias were diagnosed in children, they were often "corrected" in order to prevent stress during the psychological development, as was already said in the 1920s.
Most doctors agreed, however, that hypospadias were rarely hermaphroditic, but rather that the biological sex of those affected was clearly male, which is why psychosexual development was assumed to be naturally male.
For true hermaphrodites, on the other hand, a prediction of the psychological gender development would not be possible in principle. For this reason, during the Weimar period, most doctors were reluctant to perform genital plastic surgery on intersex children .
This position was neither explicitly endorsed nor abandoned in the medical literature of the Nazi era (with the exception of Naujoks).
With regard to the clinical practice of treatment of intersex conditions between 1933 and 1945, more questions arise than can be answered at present.
A fundamental problem of previous research is that it has been limited to analyses of the medical literature.
Medical publications in general must be met with scepticism regarding their informative value for concrete practice, as omissions, concealment and whitewashing are to be expected.
On this basis, it is not possible to answer the question of whether practices such as involuntary (or formally voluntary under extreme external coercion) cosmetic genital surgery, forced sterilizations, marriage prohibitions or abusive medical experiments were systematically carried out.
An important contribution to clarification would be an examination of the card indexes of health authorities to find out to what extent intersex newborns or adults were reported by midwives and doctors on "suspicion of serious hereditary disease", especially since in 1939 the reporting obligation was extended to include "serious malformations" without the presence of a hereditary disease.
The reports were the basis for the so-called children's euthanasia ("Kindereuthanasie"), which claimed more than 5000 children as victims.
In general, it must be noted that the National Socialists carried out the violent and murderous implementation of the racial hygiene agenda more and more drastically during their reign.
This also increased the risk for intersex people to become victims of despotism, persecution, medical experiments and extermination actions.
This is all the more true since they could be considered a danger to the Racial Corpus not only on grounds of eugenic ideation but also on a criminal and regulatory basis.
It cannot be ruled out that intersex persons were perceived as transvestites and arrested for "gross misdemeanor" or "public nuisance" .
Others may have been targeted by law enforcement authorities for same-sex activities.
It can also be assumed that intersex people were also in welfare, nursing and psychiatric institutions or in prison camps, considering their contribution to the overall population (figures vary between 0.02 and 2 percent).
For them the risk of becoming victims of cynical acts of violence and extermination was particularly high.
This applies even more so to those who were deported to concentration camps.
There are (albeit imprecise) indications in the research literature that Josef Mengele also selected "hermaphrodites" in the Auschwitz concentration camp in order to carry out his murderous human experiments on them .
Studies that specifically investigate such indications and well-founded suppositions have been lacking so far.
Clinical, institutional, judicial, official and camp files would have to be reviewed for this purpose.
In view of the relatively small number of intersex people, finding meaningful documents is an extremely difficult task.
However, this is no reason to neglect research into the fate of intersex people in the Nazi state.
On the contrary, there is an urgent need for elucidation, since intersex people were particularly at risk of becoming victims of the Nazi tyranny due to the social and medical stigmatisation.
Vgl. Intersex-Genitalverstümmelungen in Kinderkliniken: 150 Jahre Menschenversuche ohne Ethik und Gewissen (http://zwischengeschlecht.org/post/Menschenversuche-ohne-Ethik).
Intersexuelle Menschen e.V./XY-Frauen, Parallelbericht zum 6.Staatenbericht der Bundesrepublik Deutschland zum Übereinkommen der Vereinten Nationen zur Beseitigung jeder Form der Diskriminierung der Frau (CEDAW), hier S. 9 (www.institut-fuer-menschenrechte.de/fileadmin/userupload/PDF-Dateien/PakteKonventionen/ CEDAW/cedawstatereportgermany62007 parallel2de.pdf).
Due to the lack of comparable studies the author's thesis and associated research is referenced here: (Ulrike Klöppel, XX0XY ungelöst: Hermaphroditismus, Sex und Gender in der deutschen Medizin. Eine historische Studie zur Intersexualität, Bielefeld 2010, Kap. II.2.5). Further references are taken from the essay by Christian John, created 2012 at the Institut für Geschichte der Medizin der Charité under supervision by Rainer Herrn.
Vgl. Arthur Jores, Klinische Endokrinologie. Ein Lehrbuch für Ärzte und Studierende, Berlin 1939, S. 293.
Vgl.Paul Mathes, Die Konstitutionstypen des Weibes, insbesondere der intersexuelle Typus, in: Josef Halban/Ludwig Seitz (Hrsg.), Biologie und Pathologie des Weibes. Ein Handbuch der Frauenheilkunde und Geburtshilfe, Berlin/Wien 1924, S. 1–112.
Robert Stigler, Die rassenphysiologische Bedeutung der sexuellen Applanation, in: Zeitschrift für Rassenphysiologie 7 (1934), S. 67–88, hier S. 81f. und S. 86.
Vgl. Ludwig Seitz, Geschlechtliche Konstitution und geschlechtliches Hormonsystem, in: Deutsche Medizinische Wochenschrift 68 (1942), S. 741–745, hier S. 744.
Anton Priesel, Zweifelhafte Geschlechtszugehörigkeit, in: Ferdinand von Neureiter/ Friedrich Pietrusky/Eduard Schütt (Hrsg.), Handwörterbuch der gerichtlichen Medizin und naturwissenschaftlichen Kriminalistik, Berlin 1940, S. 961–969, hier S. 969.
Otto Rogal, Referat: Albin Schmidt, Die operative Behandlung des Hermaphroditis-mus, Zeitschrift für Urologie 35 (1941), S. 152–169, in: Deutsche Zeitschrift für die gesamte Gerichtliche Medizin 35 (1942), S. 501f., hier S. 502.
August Mayer, Sexualpsychologische Bedenken gegen die operative Korrektur von genitalen Bildungsstörungen, in: Zentralblatt für Gynäkologie 78 (1956), S. 1889–1892, hier S. 1892.
Otmar Freiherr von Verschuer, Pseudohermaphroditismus, in: Der Erbarzt. Beilage zum Deutschen Ärzteblatt 3 (1936), S. 192.
Hans Naujoks, Über echte Zwitterbildung beim Menschen und ihre therapeutische Beeinflussung, in: Zeitschrift für Geburtshilfe und Gynäkologie 109 (1934), S. 135–161, hier S. 148.
Vgl. Berthold Mueller/Kurt Walcher, Gerichtliche und soziale Medizin, München, Berlin 1944, S. 280f.; Hellmut Marx, Innere Sekretion, in: Gustav von Bergmann/Ru-dolf Staehelin (Hrsg.), Handbuch der Inneren Medizin, Berlin 1941, S. 1–476, hier S. 306.
Priesel, Zweifelhafte Geschlechtszugehörigkeit, S. 969.
Naujoks, Zwitterbildung beim Menschen, S. 160.
Vgl. Hans Naujoks, Über sexuelle Zwischenstufen. Vortrag auf der Sitzung der Wissenschaftlich-medizinischen Gesellschaft an der Universität Köln am 8.11.1935, in: Klinische Wochenschrift 15 (1936), S. 182.
Vgl. Walter Hartmann, Über inneren männlichen Hermaphroditismus, in: Deutsche Zeitschrift für Chirurgie 256 (1942), S. 531–545, hier S. 539; Josef Geissler, Zur Kenntnis des Pseudohermaphroditismus masculinus internus, in: Beiträge zur pathologischen Anatomie und zur allgemeinen Pathologie 100 (1937), S. 305–328.
Walter Matheja, Ein interessanter Fall von Hermaphroditismus, in: Kinderärztliche Praxis 7 (1936), S. 158f.; C. Böhner, Waltrudis oder „Walter“?, in: Zentralblatt für Chirurgie 65 (1938), S. 142 ff.
Vgl. Walther Stoeckel, Hermaphroditismus femininus externus, in: Zentralblatt für Gynäkologie 64 (1940), S. 666f.
Vgl. Adalbert Büttner/Gotthard Titze, Zur Anzeigenstellung operativer Eingriffe beim Hermaphroditismus, in: Archiv für klinische Chirurgie 261 (1948), S. 378–402, hier S. 383 ff. und S. 391 ff.
Vgl. Ludwig Moszkowicz, Soll man die Hypospadie operieren?, in: Der Chirurg 6 (1934), S. 401f.
Vgl. the contribution by Rainer Herrn in this work (ISBN ).
Vgl. Robert Jay Lifton, The Nazi Doctors. Medical Killing and the Psychology of Genocide, New York 1986, S. 360.