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Intersex, in humans and other animals, is the presence of intermediate or atypical combinations of physical features that usually distinguish female from male. This is usually understood to be congenital, involving chromosomal, morphologic, genital and/or gonadal anomalies, such as diversion from typical XX-female or XY-male presentations, e.g., sex reversal (XY female, XX male), genital ambiguity, or sex developmental differences. An intersex individual may have biological characteristics of both the male and the female sexes. Intersexuality as a term was adopted by medicine during the 20th century, and applied to human beings whose biological sex cannot be classified as clearly male or female. Intersex was initially adopted by intersex activists who criticize traditional medical approaches to sex assignment and seek to be heard in the construction of new approaches.
Some people (whether physically intersex or not) do not identify themselves as either exclusively female or exclusively male. Androgyny is sometimes used to refer to those without gender-specific physical sexual characteristics or sexual orientation or gender identity, or some combination of these; such people can be physically and psychologically anywhere between the two sexes. This state may or may not include a mixture or absence of sexual orientation.
Research in the late 20th century has led to a growing medical consensus that diverse intersex physicalities are normal, but relatively rare, forms of human biology. Milton Diamond, one of the most outspoken experts on matters affecting intersex people, stresses the importance of care in the selection of language related to such people.
|“||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.||”|
A hermaphrodite is a plant or animal that has both male and female reproductive organs.
"Disorders of sex development" (DSD) is a term that has both supporters and opponents. It is defined to include congenital conditions in which development of chromosomal, gonadal, or anatomical sex is atypical.
A number of critics of traditional terminology, including the now defunct Intersex Society of North America, intersex activists, and some medical experts moved to eliminate the term "intersex" in medical usage, replacing it with disorders of sex development 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. It is not known if this consensus is still accepted, and the ISNA is now a defunct group since its founder left it.
Other intersex people, activists, supporters, and academics have contested the adoption of the terminology and its implied status as a "disorder", seeing this as offensive to intersex individuals who do not feel that there is something wrong with them, regard the DSD consensus paper as reinforcing the normativity of early surgical interventions, and criticising the treatment protocols associated with the new taxonomy. Alternatives to categorising intersex conditions as "disorders" have been suggested, including "variations of sex development". Organisation Intersex International questions a disease/disability approach, argues for deferral of intervention unless medically necessary, when fully informed consent of the individual involved is possible, and self-determination of sex/gender orientation and identity.
Intersex people are treated in different ways by different cultures. In some cultures, such people were included in larger "third gender" or gender-blending social roles along with other individuals. In most societies, intersexed people have been expected to conform to either a female or a male gender role.
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. An example is one of the Sumerian creation myths from more than 4,000 years ago. The story 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.
During the Victorian era, medical authors introduced the terms "true hermaphrodite" for an individual who has both ovarian and testicular tissue, 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. In Europe, the term 'intersexual' was first to be used before the Second World War. The first suggestion to replace the term 'hermaphrodite' with 'intersex' came from British specialist Cawadias in the 1940s. This suggestion was taken up by specialists in the UK during the 1960s, by both those who rejected Money's framework (then emerging from the USA), and those who endorsed that approach.
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 female or male genitals. 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. Awareness of the existence of physical sexual variation in human beings has increased.
Some groups, such as ISNA, and some clinicians, such as those at University College Hospital London, have questioned the practice of performing genital corrective surgery on intersex children. Dialogue between what were once antagonistic groups of activists and clinicians has led to changes in medical policies and how intersex patients and their families are treated in some locations. There are intersex groups, such as OII, who argue that the various degrees of intersex are natural human variations that should not be subject to correction.
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 female and male. Her terms were "tongue-in-cheek"; she no longer advocates these terms even as a rhetorical device. The activist Cheryl Chase criticized these terms in a letter to The Sciences, also criticizing the traditional standard of medical care. Chase announced the creation of the Intersex Society of North America.
The first sociologist to work on 'intersexuality' was Harold Garfinkel in 1967 using a method derived from sociological phenomenology he called ethnomethodology. He based his analysis on the everyday commonsense understandings of 'Agnes', a woman undergoing social and surgical gender reassignment. Ethnomethodology was also used in 1978 by Kessler and McKenna, who argue that, while gender can be seen as a social accomplishment, cross-cultural studies render gender as problematic as they highlight how it is usually regarded as a fact, when it can be shown to be constructed in different ways. They point to different cultural approaches to gender roles, and how 'hermaphrodites' and 'berdaches' are incorporated socially, as disruptive to fixed ideas about sex, gender, and gender-roles. They argue that what we 'know' about gender is grounded in the 'everyday social construction of a world of two genders', where gender attribution seems more important than gender differentiation.
Depending on the type of intersex condition, surgery may be performed not for protection of life or health but 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 may 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. Opponents claim this led 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. The Declaration of Montreal first demanded prohibition of unnecessary post-birth surgery to reinforce gender assignment until a child is old enough to understand and give informed consent. This was detailed in the context of existing UN declarations and conventions under Principle 18 of The Yogyakarta Principles, which called on states to:
B. Take all necessary legislative, administrative and other measures to ensure that no child’s body is irreversibly altered by medical procedures in an attempt to impose a gender identity without the full, free and informed consent of the child in accordance with the age and maturity of the child and guided by the principle that in all actions concerning children, the best interests of the child shall be a primary consideration;
C. Establish child protection mechanisms whereby no child is at risk of, or subjected to, medical abuse;
— The Yogyakarta Principles
Intersex advocates and experts have critiqued the necessity of early interventions, citing individual's experiences of intervention and the lack of follow-up studies showing clear benefits. Specialists at the Intersex Clinic at University College London began to publish evidence in 2001 that indicated the harm that can arise as a result of inappropriate interventions, and advised minimising the use of childhood surgical procedures.
Photographs of intersex children's genitalia are circulated in medical communities for documentary purposes; an example of this appears in the medical section 3.2.1 below. Problems associated with experiences of medical photography of intersex children have been discussed along with the ethics, control and usage.
"The experience of being photographed has exemplified for many people with intersex conditions the powerlessness and humiliation felt during medical investigations and interventions".
The proposed revisions for DSM-5 include a change from using Gender Identity Disorder to Gender Dysphoria. This revised code now specifically includes intersex people as people with Disorders of Sex Development. This move has been criticised by one intersex advocacy group in Australia, and criticism from the intersex community has been lodged with the appropriate DSM5 subcommittee.
Intersex was discussed on British TV for the first time in 1966, and became a topic of interest for broadcast TV and radio in the United States and other countries from 1989. Jeffrey Eugenides' novel Middlesex (2002) is narrated by an intersex character who discusses the societal experience of an intersex person. The Japanese manga series I.S., first published in 2003, features intersexual characters and how they deal with intersex-related issues and influence the lives of people around them. The Japanese manga series After School Nightmare features a hermaphrodite as its protagonist, who identifies as male but has female genitalia.
Also in Lois McMaster Bojould's Vorkosigan series, genetically engineered hermaphrodites make up a significant part of the off-world population.
The 2007 Argentine film XXY centres around a young intersex person who is assisted in presenting as a girl with medication. The film deals with discrimination, sexuality and gender identity.
More recently (2010), Australian documentary-maker, Phoebe Hart, directed an autobiographical documentary of her personal experience as an Intersex. The film, Orchids, My Intersex Adventure, explores the various social scenarios faced by many Intersex individuals.
Intersexion - award of the Best Feature Documentary at the Documentary Edge Festival (2012) hosted by Mani Bruce Mitchell, CEO of the first Intersex Trust in the world (ITANZ), directed by Grant Lahood. The film follows Mani as s/he visits intersex people in America, Ireland, Germany, South Africa and Australia.
In secondary schools, biology and sex education instructors often place most emphasis on the most common XX and XY genotypes. Thus, people nowadays may be more likely to look towards the sex chromosomes than, for example, the histology of the gonads. However, according to researcher Eric Vilain at the University of California, Los Angeles, "the biology of gender is far more complicated than XX or XY chromosomes". Many different criteria have been proposed, and there is little consensus.
There are a variety of opinions on what conditions are and are not intersex. For instance, the defunct Intersex Society of North America (ISNA) definition states that the following conditions "sometimes involve intersex anatomy" (note this does not mean they are always intersex conditions):
The prevalence of intersex depends on which definition is used.
According to the ISNA definition above, 1 percent of live births exhibit some degree of sexual ambiguity. 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.
|“||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%.
Ambiguous genitalia appear as a large clitoris or small penis and may or may not require surgery.
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 outdated 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.
With some conditions of intersex, even the chromosomal sex may not be clear. A "true hermaphrodite" is defined as someone with both male gonadal tissue (testes) and female gonadal tissue (ovarian tissue).
In 2003, researchers at UCLA published their studies of a lateral gynandromorphic hermaphroditic zebra finch, which had a testicle on the right and an ovary on the left. Its entire body was split down the middle between female and male, with hormones from both gonads running through the blood. This is an example of mosaicism or chimerism.
This extreme example of hermaphroditism is quite rare.
Though naturally occurring true hermaphroditism in humans is unknown, there is, on the other hand, a spectrum of forms of ovotestes. The varieties include having two ovotestes or one ovary and one ovotestis, often in the form of streak gonads. Phenotype is not determinable from the ovotestes; in some cases, the appearance is "fairly typically female"; in others, it is "fairly typically male," and it may also be "fairly in-between in terms of genital development."
In order to help in classification, methods other than a genitalia inspection can be performed:
For instance, a karyotype display of a tissue sample may determine which of the causes of intersex is prevalent in the case.
Clinical management of intersex can be categorized into one of the following two:
However, there are other categorisation systems of management of intersexed, which falls into neither category.
In any case, the most common procedure is surgery.
The exact procedure of the surgery depends on what is the cause of a less common body phenotype in the first place. There is often concern as to whether surgery should be performed at all. A traditional approach to the management of intersexuality has been socially motivated surgery. However, some (Alice Dreger) say that surgical treatment is socially motivated and, hence, ethically questionable; without evidence, doctors regularly assume that intersexed persons cannot have a clear identity. This is often taken further with parents of intersexed babies advised that without surgery their child will be stigmatized. Further, since almost all such surgeries are undertaken to fashion female genitalia for the child, it is more difficult for the child to present as male if they later select a male gender identity. 20-50% of surgical cases result in a loss of sexual sensation (Newman 1991, 1992).
As convention, 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.
The common pathway of sexual differentiation, where a productive human female has an XX chromosome pair, and a productive male has an XY pair, is relevant to the development of intersexed conditions.
During fertilization, the sperm adds either an X (female) or a 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, female and male 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.
|This section needs additional citations for verification. (April 2010)|
The final body appearance does not always correspond with what is dictated by the genes. In other words, there is sometimes an incongruity between genotypic (chromosomal) and phenotypic sex. Citing medical research regarding other factors that influence sexual differentiation, the Intersex Society of North America challenges the XY sex-determination system's assumption that chromosomal sex is the determining factor of a person's "true" biological sex.
|XX||Congenital adrenal hyperplasia (CAH)||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 people without a Y chromosome (i.e., XX), this can range from partial masculation that produces a large clitoris, to virilisation and male appearance. The latter applies in particular to Congenital adrenal hyperplasia due to 21-hydroxylase deficiency, which is the most common form of CAH.
Individuals born with XX chromosomes affected by 17α-hydroxylase deficiency are born with female internal and external anatomy, but, at puberty, neither the adrenals nor the ovaries can produce sex-hormones, inhibiting breast development and the growth of pubic hair.
See below for XY CAH 17α-hydroxylase deficiency.
|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 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 males.|
|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 (AIS)||People with AIS have a Y chromosome, (typically XY), but are unable to metabolize androgens in varying degrees. |
Cases with typically female appearance and genitalia are said to have complete androgen insensitivity syndrome (CAIS). People with CAIS have a vagina and no uterus, cervix, or ovaries, and are infertile. The vagina may be shorter than usual, and, in some cases, is nearly absent. Instead of female internal reproductive organs, a person with CAIS has undescended or partially descended testes, of which the person may not even be aware.
In mild and partial androgen insensitivity syndrome (MAIS and PAIS), the body is partially receptive to androgens, so there is virilization to varying degrees. PAIS can result in genital ambiguity, due to limited metabolization of the androgens produced by the testes. Ambiguous genitalia may present as a large clitoris, known as clitoromegaly, or a small penis, which is called micropenis or microphallus; hypospadias and cryptorchidism may also be present, with one or both testes undescended, and hypospadias appearing just below the glans on an otherwise typical male penis, or at the base of the shaft, or at the perineum and including a bifid (or cleft) scrotum.
|XY||5-alpha-reductase deficiency (5-ARD)||The condition affects individuals with a Y chromosome, making their bodies unable to convert testosterone to dihydrotestosterone (DHT). DHT is necessary for the development of male genitalia in utero, and plays no role in female development, so its absence tends to result in ambiguous genitalia at birth; the effects can range from infertility with male genitalia to male underdevelopment with hypospadias to female genitalia with mild clitoromegaly. The frequency is unknown, and children are sometimes misdiagnosed as having AIS. Individuals can have testes, as well as vagina and labia, and a small penis capable of ejaculation that looks like a clitoris at birth. Such individuals are usually raised as girls. The lack of DHT also limits the development of facial hair.|
|XY||Congenital adrenal hyperplasia (CAH)||In individuals with a Y chromosome (typically XY) who have Congenital adrenal hyperplasia due to 17 alpha-hydroxylase deficiency, CAH inhibits virilization, unlike cases without a Y chromosome.|
|XY||Persistent Müllerian duct syndrome (PMDS)||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||Anorchia||Individuals with XY chromosomes whose gonads were lost after 14 weeks of fetal development. People with Anorchia have no ability to produce the hormones responsible for developing male secondary sex characteristics nor the means to produce gametes necessary for reproduction due to the lack of gonads. They may develop typically feminine secondary sex characteristics without or despite the administration of androgens to artificially initiate physical sex differentiation (typically planned around the age of puberty). Psychological and neurological gender identity may solidify before the administration of androgens, leading to gender dysphoria, as anorchic individuals are typically assigned male at birth.|
|Other||Unusual chromosomal sex||In addition to the most common XX and XY chromosomal sexes, there are several other possible combinations, for example Turner syndrome (XO), Triple X syndrome (XXX), Klinefelter's Syndrome, (XXY/XXXY), XYY syndrome (XYY), de la Chapelle syndrome (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, whereas chimerism is a fusion of two embryos. |
In alternative fashion, it is simply a mixture between XX and XY, and does not have to involve any less-common genotypes in individual cells. This, too, can occur both as chimerism and as a result of one sex chromosome having mutated into the other.
However, not all cases of mosaicism and chimerism involve intersex.
In the cases where nonfunctional testes are present, there is a risk that these develop cancer. Therefore, doctors either remove them by orchidectomy or monitor them carefully. This is the case for instance in androgen insensitivity syndrome.