Intersexuality is the term adopted by medicine during the 20th century applied to human beings who cannot be classified as either male or female.
Intersexuality is also the word adopted by the identitary-political movement, to criticize medical protocols in sex assignment and to claim the right to be heard in the construction of a new one.
Foremost, we advocate use of the terms "typical," "usual," or "most frequent" where it is more common to use the term "normal." When possible avoid expressions like maldeveloped or undeveloped, errors of development, defective genitals, abnormal, or mistakes of nature. Emphasize that all of these conditions are biologically understandable while they are statistically uncommon.
The Intersex Society of North America and intersex activists have moved to eliminate the term "intersex" in medical usage, replacing it with "disorders of sex development" (DSD) in order to avoid conflating anatomy with identity. Members of The Lawson Wilkins Pediatric Endocrine Society and the European Society for Paediatric Endocrinology accepted this term in their "Consensus statement on management of intersex disorders" published in the Archives of Disease in Children and in Pediatrics.
The term is defined by congenital conditions in which development of chromosomal, gonadal, or anatomical sex is atypical. However, this has been met with criticism from other activists who question a disease/disability model and advocate no legal definition of sexes, no gender assignments, no legal sex on birth certificates, and no official sexual orientation categories. Alternatives to labeling these as "disorders" have also been suggested, including "variations of sex development".
Whether or not they were socially tolerated or accepted by any particular culture, the existence of intersex people was known to many ancient and pre-modern cultures.
As an example, one of the Sumerian creation myths from more than 4,000 years ago has Ninmah, a mother goddess, fashioning mankind out of clay. She boasts that she will determine the fate – good or bad – for all she fashions. Enki, the father god, retorts as follows.
Since the rise of modern medical science in Western societies, some intersex people with ambiguous external genitalia have had their genitalia surgically modified to resemble either male or female genitals. Ironically since the advancements in surgery have made it possible for intersex conditions to be concealed, many people are not aware of how frequently intersex conditions arise in human beings or that they occur at all. Contemporary social activists, scientists and health practitioners, among others, have begun to revisit the issue, and awareness of the existence of physical sexual variation in human beings is returning.
There are increasing calls for recognition of the various degrees of intersex as healthy variations which should not be subject to correction. Some have attacked the common Western practice of performing corrective surgery on the genitals of intersex people as a Western cultural equivalent of female genital cutting. Despite the attacks on the practice, most of the medical profession still supports it, although activism has radically altered medical policies and how intersex patients and their families are treated. Others, typically social conservatives, have claimed that the talk about third sexes represents an ideological agenda to deride gender as a social construct whereas they believe binary gender (i.e. there is only male and female) is a biological imperative.
Depending on the type of intersex condition, corrective surgery may not be necessary for protection of life or health, but purely for aesthetic or social purposes. Unlike other aesthetic surgical procedures performed on infants, such as corrective surgery for a cleft lip (as opposed to a cleft palate), genital surgery may lead to negative consequences for sexual functioning in later life (such as loss of sensation in the genitals, for example, when a clitoris deemed too large/penile is reduced/removed, or feelings of freakishness and unacceptability) which would have been avoided without the surgery; in other cases negative consequences may be avoided with surgery. Opponents maintain that there is no compelling evidence that the presumed social benefits of such "normalizing" surgery outweigh the potential costs.(Similar attitudes are present in some cases of botched infant circumcision, in which the solution might involve intensive medical and parental efforts to reassign the male baby to a female identity, which opponents claim lead to the degrading interpretation that females are essentially castrated males. This view overlooks the embryological origin of the penis/clitoris.) Defenders of the practice argue that it is necessary for individuals to be clearly identified as male or female in order for them to function socially. However, many intersex individuals have resented the medical intervention, and some have been so discontented with their surgically assigned gender as to opt for sexual reassignment surgery later in life.
During the Victorian era, medical authors introduced the terms "true hermaphrodite" for an individual who has both ovarian and testicular gonadal histology, verified under a microscope, "male pseudo-hermaphrodite" for a person with testicular tissue, but either female or ambiguous sexual anatomy, and "female pseudo-hermaphrodite" for a person with ovarian tissue, but either male or ambiguous sexual anatomy. The writer Anne Fausto-Sterling coined the words herm (for "true hermaphrodite"), merm (for "male pseudo-hermaphrodite"), and ferm (for "female pseudo-hermaphrodite"), and proposed that these be recognized as sexes along with male and female. However, her use was "tongue-in-cheek"; she no longer advocates these terms even as a rhetorical device, and her proposed nomenclature was criticized by Cheryl Chase, in a letter to The Sciences which criticized the traditional standard of medical care as well as Fausto-Sterling's shorter names, and announced the creation of the Intersex Society of North America.
For instance, the Intersex Society of North America (ISNA) definition states that the following conditions "sometimes involve intersex anatomy":
According to the ISNA definition above, 1 percent of live births exhibit some degree of sexual ambiguity, approximately one in every hundred births. Between 0.1% and 0.2% of live births are ambiguous enough to become the subject of specialist medical attention, including surgery to disguise their sexual ambiguity.
According to Fausto-Sterling's definition of intersex, on the other hand, 1.7 percent of human births are intersex. She writes,
While male and female stand on the extreme ends of a biological continuum, there are many bodies [...] that evidently mix together anatomical components conventionally attributed to both males and females. The implications of my argument for a sexual continuum are profound. If nature really offers us more than two sexes, then it follows that our current notions of masculinity and femininity are cultural conceits. [...] Modern surgical techniques help maintain the two-sex system. Today children who are born "either/or-neither/both" — a fairly common phenomenon — usually disappear from view because doctors "correct" them right away with surgery.|
According to Leonard Sax the prevalence of intersex "restricted to those conditions in which chromosomal sex is inconsistent with phenotypic sex, or in which the phenotype is not classifiable as either male or female" is about 0.018%.
Because there is variation in all of the processes of the development of the sex organs, a child can be born with a sexual anatomy that is typically female, or feminine in appearance with a larger than average clitoris (clitoral hypertrophy); or typically male, masculine in appearance with a smaller than average penis that is open along the underside. The appearance may be quite ambiguous, describable as female genitals with a very large clitoris and partially fused labia, or as male genitals with a very small penis, completely open along the midline ("hypospadic"), and empty scrotum.
Fertility is variable. According to some,the distinctions "male pseudohermaphrodite", "female pseudohermaphrodite" and especially "true hermaphrodite are vestiges of 19th century thinking. According to others, the terms "male pseudohermaphrodite", and "female pseudohermaphrodite" are used to define the gender in terms of the histology (microscopic appearance) of the gonads.
In 2004, researchers at UCLA published their studies of a lateral gynandromorphic hermaphroditic bird, which had a testicle on the right and an ovary on the left. Its entire body was split down the middle between male and female, with hormones from both gonads running through the blood.
This extreme example of hermaphroditism is quite rare.
Intersex activist Cheryl Chase is an example of someone with ovotestes.
For instance, a karyotype display of a tissue sample may determine which of the causes of intersex is prevalent in the case.
However, there are other categorisation systems of management of intersexed, which falls into neither category.
In any case, the most common procedure is surgery.
Conventionally, surgery is performed at birth. Intersex advocates such as Anne Fausto-Sterling in her Sexing the Body argue surgery on intersexed babies should wait until the child can make an informed decision, and label operation without consent as genital mutilation.
During fertilization, the sperm adds either an X (female) or Y (male) chromosome to the X in the ovum. This determines the genetic sex of the embryo. During the first weeks of development, genetic male and female fetuses are "anatomically indistinguishable," with primitive gonads beginning to develop during approximately the sixth week of gestation. The gonads, in a "bipotential state," may develop into either testes (the male gonads) or ovaries (the female gonads) depending on the consequent events. Through the seventh week, male and female fetuses appear identical.
At around eight weeks of gestation, the gonads of an XY embryo differentiate into functional testes, secreting testosterone. Ovarian differentiation, for XX embryos, does not occur until approximately Week 12 of gestation. In normal female differentiation the Müllerian duct system develops into the uterus, Fallopian tubes, and inner third of the vagina. In males the Müllerian duct-inhibiting hormone MIH causes this duct system to regress. Next, androgens cause the development of the Wolffian duct system, which develops into the vas deferens, seminal vesicles, and ejaculatory ducts. By birth, the typical fetus has been completely "sexed" male or female, the hormones and genital development remaining consistent with the genetic sex.
The final body appearance doesn't always correspond with what is dictated by the genes. In other words, there is sometimes an incongruence between genotypic (chromosomal) and phenotypic sex. Although there neither no less common chromosomal sex nor mosaicism/chimerism, but just the most common types (XY or XX), less common phenotypes still appear in such cases. In this sense, the common habit in the 21st century of elevating the role of the sex chromosomes above all other factors when determining gender may be analogous to the older habit of finding "true" sex in the gonads.
This phenomenon complicates the common XY sex-determination system, because it proves that genes don't always definitely correlate to one's perceived sex.
|XX||Congenital adrenal hyperplasia||The most common cause of sexual ambiguity is congenital adrenal hyperplasia (CAH), an endocrine disorder in which the adrenal glands produce abnormally high levels of virilizing hormones. In genetic females, this leads to an appearance that may be slightly masculinized (large clitoris) to quite masculine.|
|XX||Progestin-induced virilisation||In this case, the male hormones are caused by use of progestin, a drug that was used in the 1950s and 1960s in order to prevent miscarriage. These individuals normally have internal and external female anatomy, with functional ovaries and will therefore have menstruation. They develop, however, some male secondary characteristics and they frequently have unusually large clitorises. In very advanced cases, such children have initially been identified as boys .|
|XX||Freemartinism||This condition occurs commonly in all species of cattle and affects most females born as a twin to a male. It is rare or unknown in other mammals, including humans. In cattle, the placentae of fraternal twins usually fuse at some time during the pregnancy, and the twins then share their blood supply. If the twins are of different sexes, male hormones produced in the body of the fetal bull find their way into the body of the fetal heifer (female), and masculinize her. Her sexual organs do not develop fully, and her ovaries may even contain testicular tissue. When adult, such a freemartin is very like a normal female in external appearance, but she is infertile, and behaves more like a castrated male (a steer). The male twin is not significantly affected, although (if he remains entire) his testes may be slightly reduced in size. The degree of masculinization of the freemartin depends on the stage of pregnancy at which the placental fusion occurs in about ten percent of such births no fusion occurs and both calves develop normally as in other mammals.|
|XY||Androgen insensitivity syndrome|| People with AIS have typically male chromosomes (XY), along with typically female appearance and genitalia. Although people with AIS have a vagina, they lack a uterus, cervix of the uterus, and ovaries, and are thereby infertile. The vagina may be shorter than average; in some cases it is nearly absent. Instead of female internal reproductive organs, a person with AIS has undescended or partially descended testes, of which the person may not even be aware.|
AIS may be called the genetic male's equivalent of CAH, since AIS affects people with XY genotype, while CAH affects people with XX genotype.
In complete androgen insensitivity syndrome ("CAIS"), the body reads no "male" hormones. In partial androgen insensitivity syndrome (PAIS), however, the body reads some androgens, so virilization occurs to a certain degree. PAIS results in genitalia that may be ambiguous, due to some, although limited, metabolization of the hormones produced by the testes. Ambiguous genitalia most frequently appear as a large clitoris, known as clitoromegaly, or a small penis, which is called as micropenis or microphallus.
|XY||5-alpha-reductase deficiency||In this condition, individuals have testes, as well as vagina and labia, but with a small penis capable of ejaculation instead of a clitoris (this penis, however, appears to be a clitoris at birth). These individuals are normally raised as girls. However, come puberty, their testes will descend, their voice will deepen and they often will develop a male sexual identity. People with this deficiency develop only limited facial hair.|
|XY||Persistent Müllerian duct syndrome||The child has XY chromosomes typical of a male. The child has a male body and an internal uterus and fallopian tubes because his body did not produce Müllerian inhibiting factor during fetal development.|
|XY||Kallmann syndrome||This is a specific type of hypogonadotropic hypogonadism (HH) in which the distinguishing symptom is anosmia or hyposmia in addition to the HH symptoms of low levels of pituitary hormones LH and FSH. Kallmann Syndrome is an intersex condition but does cause pubertal delay in both males and females. Some individuals with Kallmann's consider themselves as intersex though some do not. However, this is possibly because they have other conditions such as PAIS in addition to Kallmann's. Such synchronous conditions is only present in a minority of people with Kallmann's, who mostly have no genital abnormality at birth.|
|Other||Less usual chromosomal sex||In addition to the most common XX and XY chromosomal sexes, there are quite a few other possible combinations such as Turner syndrome (XO), Triple X syndrome (XXX), Klinefelter syndrome (XXY), XYY syndrome (XYY), XX male, Swyer syndrome (XY female), and there are many other individuals who do not follow the typical patterns (such as individuals with four or even more sex chromosomes).|
|Other||Mosaicism and chimerism|| A mix can occur, where some of the cells of the body have the common XX or XY, while some have one of the less usual chromosomal contents above. Such a mixture is caused by either mosaicism or chimerism. In mosaicism, the mixture is caused by a mutation in one of the cells of the embryo after fertilization, while chimerism is a fusion of two embryos. Alternatively, it is simply is a mixture between XX and XY, and doesn't have to involve any less common genotypes in individual cells. This, too, can occur both as a chimerism, or that one sex chromosome has mutated into the other.|
On the other hand, however, not all cases of mosaicism and chimerism involve intersex.
It should be noted however that there is a growing political intersex movement which argues against labeling these categories as disorders.