Sex assignment
Encyclopedia
Sex assignment refers to the assigning (naming) of the biological sex
Sex
In biology, sex is a process of combining and mixing genetic traits, often resulting in the specialization of organisms into a male or female variety . Sexual reproduction involves combining specialized cells to form offspring that inherit traits from both parents...

 at the birth
Childbirth
Childbirth is the culmination of a human pregnancy or gestation period with the birth of one or more newborn infants from a woman's uterus...

 of a baby. In the majority of births, a relative, midwife, or physician
Physician
A physician is a health care provider who practices the profession of medicine, which is concerned with promoting, maintaining or restoring human health through the study, diagnosis, and treatment of disease, injury and other physical and mental impairments...

 inspects the genitalia when the baby is delivered, sees ordinary male
Male
Male refers to the biological sex of an organism, or part of an organism, which produces small mobile gametes, called spermatozoa. Each spermatozoon can fuse with a larger female gamete or ovum, in the process of fertilization...

 or female
Female
Female is the sex of an organism, or a part of an organism, which produces non-mobile ova .- Defining characteristics :The ova are defined as the larger gametes in a heterogamous reproduction system, while the smaller, usually motile gamete, the spermatozoon, is produced by the male...

 genitalia, and declares, "it's a girl" or "it's a boy" without the expectation of ambiguity. Assignment may also be done prior to birth through prenatal sex discernment
Prenatal sex discernment
Prenatal sex discernment is the prenatal testing for discerning the sex of a fetus before birth.-Methods:Prenatal sex discernment can be performed by preimplantation genetic diagnosis before conception....

. The assignment is perceived as a recognition of an essential aspect of a baby, apparent to everyone. In nearly all cases, usually without conscious deliberation, the parents rear the child as a member of the assigned sex/gender
Gender
Gender is a range of characteristics used to distinguish between males and females, particularly in the cases of men and women and the masculine and feminine attributes assigned to them. Depending on the context, the discriminating characteristics vary from sex to social role to gender identity...

.

The act of assignment is a social act, and is in nearly all cases, and all societies, an act that seems a simple recognition of a simple biological reality. However, the usual act of assignment carries with it some conscious and unconscious assumptions, namely that the external genitalia reflect other aspects of biological sex
Sex
In biology, sex is a process of combining and mixing genetic traits, often resulting in the specialization of organisms into a male or female variety . Sexual reproduction involves combining specialized cells to form offspring that inherit traits from both parents...

, such as internal anatomy, gonad
Gonad
The gonad is the organ that makes gametes. The gonads in males are the testes and the gonads in females are the ovaries. The product, gametes, are haploid germ cells. For example, spermatozoon and egg cells are gametes...

s, hormone
Hormone
A hormone is a chemical released by a cell or a gland in one part of the body that sends out messages that affect cells in other parts of the organism. Only a small amount of hormone is required to alter cell metabolism. In essence, it is a chemical messenger that transports a signal from one...

s, and chromosome
Chromosome
A chromosome is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.Chromosomes...

s. The act of assignment usually carries the implicit expectation that future gender identity
Gender identity
A gender identity is the way in which an individual self-identifies with a gender category, for example, as being either a man or a woman, or in some cases being neither, which can be distinct from biological sex. Basic gender identity is usually formed by age three and is extremely difficult to...

 will develop in the gender of anatomy, assignment, and rearing.

In a minority of cases, the assigned sex or one or more of these related assumptions prove to be false. In the case of some transgender
Transgender
Transgender is a general term applied to a variety of individuals, behaviors, and groups involving tendencies to vary from culturally conventional gender roles....

 individuals or intersex
Intersex
Intersex, in humans and other animals, is the presence of intermediate or atypical combinations of physical features that usually distinguish female from male...

 individuals, gender identity does not simply follow the assigned sex or sex of rearing. There have also been rare instances where parents (for a variety of reasons) have reared an anatomically typical child in the opposite gender. In some conditions usually termed intersex
Intersex
Intersex, in humans and other animals, is the presence of intermediate or atypical combinations of physical features that usually distinguish female from male...

, internal anatomy may not be consistent with assumptions based on external anatomy.

Assignment in intersex conditions

Intersex
Intersex
Intersex, in humans and other animals, is the presence of intermediate or atypical combinations of physical features that usually distinguish female from male...

 is a broadly defined term that usually denotes the presence of discordance of the biological aspects of sex: at least some aspect of the genitalia, internal organs, gonad
Gonad
The gonad is the organ that makes gametes. The gonads in males are the testes and the gonads in females are the ovaries. The product, gametes, are haploid germ cells. For example, spermatozoon and egg cells are gametes...

al tissue, or chromosome
Chromosome
A chromosome is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.Chromosomes...

s is more typical of the other sex, or incompletely differentiated
Sexual differentiation
Sexual differentiation is the process of development of the differences between males and females from an undifferentiated zygote...

. When the external genitalia appear to be "in between", they are described as ambiguous.

In approximately 1 in 5,000 infants there is enough variation in the appearance of the external genitalia to give rise to hesitation about appropriate assignment by the physician involved. Typical examples would be an unusually prominent clitoris
Clitoris
The clitoris is a sexual organ that is present only in female mammals. In humans, the visible button-like portion is located near the anterior junction of the labia minora, above the opening of the urethra and vagina. Unlike the penis, which is homologous to the clitoris, the clitoris does not...

 in an otherwise apparently normal girl, or complete cryptorchidism
Cryptorchidism
Cryptorchidism is the absence of one or both testes from the scrotum. It is the most common birth defect regarding male genitalia. In unique cases, cryptorchidism can develop later in life, often as late as young adulthood. About 3% of full-term and 30% of premature infant boys are born with at...

 or mild hypospadias
Hypospadias
Hypospadias is a birth defect of the urethra in the male that involves an abnormally placed urinary meatus...

 in an otherwise apparently normal boy. In most of these cases, a sex is tentatively assigned and the parents told that tests will be performed to quickly confirm the apparent sex. Typical tests in this situation might include a pelvic ultrasound
Ultrasound
Ultrasound is cyclic sound pressure with a frequency greater than the upper limit of human hearing. Ultrasound is thus not separated from "normal" sound based on differences in physical properties, only the fact that humans cannot hear it. Although this limit varies from person to person, it is...

 to detect a uterus
Uterus
The uterus or womb is a major female hormone-responsive reproductive sex organ of most mammals including humans. One end, the cervix, opens into the vagina, while the other is connected to one or both fallopian tubes, depending on the species...

, a testosterone
Testosterone
Testosterone is a steroid hormone from the androgen group and is found in mammals, reptiles, birds, and other vertebrates. In mammals, testosterone is primarily secreted in the testes of males and the ovaries of females, although small amounts are also secreted by the adrenal glands...

 or 17-hydroxyprogesterone
17-Hydroxyprogesterone
17-Hydroxyprogesterone is a C-21 steroid hormone produced during the synthesis of glucocorticoids and sex steroids.As a hormone, 17OHP also interacts with the progesterone receptor.-Production:...

 level, and/or a karyotype
Karyotype
A karyotype is the number and appearance of chromosomes in the nucleus of an eukaryotic cell. The term is also used for the complete set of chromosomes in a species, or an individual organism.p28...

. In some of these cases a pediatric endocrinologist is consulted to confirm the tentative sex assignment. The expected assignment is usually confirmed within hours to a couple of days in these cases.

In a much smaller proportion of cases, the process of assignment is more complex, and involves both determining what the biological levels of sex may be as well as choosing the best sex assignment. Approximately 1 in 20,000 infants is born with enough ambiguity that assignment becomes a more drawn-out process of multiple tests and intensive education of the parents about sexual differentiation
Sexual differentiation
Sexual differentiation is the process of development of the differences between males and females from an undifferentiated zygote...

. In some of these cases, it is clear that the child will face major discordances or abnormalities of anatomy or function as he or she grows up, and deciding upon the sex of assignment is a matter of weighing the advantages and disadvantages of either assignment.

Criteria for assignment in these cases have evolved over the decades, as our understanding of the biological factors and our diagnostic tests have improved, as surgical
Intersex surgery
Intersex surgery is one of several terms referring to surgery performed to correct birth defects or early injuries of the genitalia, primarily for the purposes of making the appearance more normal and to reduce the likelihood of future problems...

 techniques have changed and potential complications have become clearer, and in response to the outcomes and opinions of adults who have grown up with various intersex conditions.

The following is a brief review of the history of the criteria for sex assignment in intersex cases.

Before the 1950s, assignment was based almost entirely on the appearance of the external genitalia. Although physicians recognized that there were conditions in which the apparent secondary sexual characteristics could develop contrary to the person's sex, and conditions in which the gonadal sex did not match that of the external genitalia, their ability to understand and diagnose such conditions in infancy was too poor to attempt to predict future development in most cases.

In the 1950s, endocrinologists developed a basic understanding of the major intersex conditions: (congenital adrenal hyperplasia
Congenital adrenal hyperplasia
Congenital adrenal hyperplasia refers to any of several autosomal recessive diseases resulting from mutations of genes for enzymes mediating the biochemical steps of production of cortisol from cholesterol by the adrenal glands ....

 (CAH), androgen insensitivity syndrome
Androgen insensitivity syndrome
Androgen insensitivity syndrome is a condition that results in the partial or complete inability of the cell to respond to androgens. The unresponsiveness of the cell to the presence of androgenic hormones can impair or prevent the masculinization of male genitalia in the developing fetus, as...

, mixed gonadal dysgenesis
Mixed gonadal dysgenesis
Mixed gonadal dysgenesis is a condition of unusual and asymmetrical gonadal development leading to an unassigned sex differentiation. A number of differences have been reported in the karyotype, most commonly a mosaicism 45,X/ 46, XY...

 and other chromosomal abnormalities. The discovery of cortisone
Cortisone
Cortisone is a steroid hormone. It is one of the main hormones released by the adrenal gland in response to stress. In chemical structure, it is a corticosteroid closely related to corticosterone. It is used to treat a variety of ailments and can be administered intravenously, orally,...

 allowed survival of infants with severe CAH for the first time. New hormone tests and karyotypes allowed more confident diagnosis in infancy and prediction of future development. Surgeons began to devise techniques for repairing the perceived abnormalities of the genitalia. Undescended testes could be retrieved, and hypospadias and chordee usually successfully assigned. A greatly enlarged clitoris could be amputated to the usual size, but attempts to create a penis were unsuccessful. John Money
John Money
John William Money was a psychologist, sexologist and author, specializing in research into sexual identity and biology of gender...

 and others observed that children with the same types of intersex condition might have been raised as different sexes, and were more likely to develop a gender identity that matched sex of rearing than sex of chromosomes, gonads, or hormones. He also reported that gender identity was usually developed and "set" by early childhood, such that attempts by parents and doctors to reassign sex at an older age was rarely successful. Endocrinologists and surgeons began to base sex assignment in difficult cases not just on the external genitalia, but on the internal genitalia, on the expected future response to testosterone, and on potential fertility.

In the 1960s, surgical confidence with birth defect
Congenital disorder
A congenital disorder, or congenital disease, is a condition existing at birth and often before birth, or that develops during the first month of life , regardless of causation...

 advanced, as did the acceptability and experience with adult sex reassignment surgery. Pediatric surgeons attempted and claimed success with reconstruction of infant genitalia, especially enlargement or construction of vagina
Vagina
The vagina is a fibromuscular tubular tract leading from the uterus to the exterior of the body in female placental mammals and marsupials, or to the cloaca in female birds, monotremes, and some reptiles. Female insects and other invertebrates also have a vagina, which is the terminal part of the...

s. The view of gender
Gender
Gender is a range of characteristics used to distinguish between males and females, particularly in the cases of men and women and the masculine and feminine attributes assigned to them. Depending on the context, the discriminating characteristics vary from sex to social role to gender identity...

 as a purely social construction, and gender identity as a result of "nurture" rather than "nature" reached near-universal acceptance, especially among liberal, progressive, and academic portions of Western society. The primary goal of assignment was to choose the sex that would lead to the least inconsistency between external anatomy and psyche (gender identity). This led to the recommendation that any child without a penis could be raised as a girl, taught to be a girl, and would develop a female gender identity, and that this would be the best way to minimize future discrepancy between psyche and external anatomy in those few biologically male infants unfortunate enough to be born with an irreparably defective penis (e.g., cloacal exstrophy
Cloacal exstrophy
Cloacal exstrophy is a severe birth defect wherein much of the abdominal organs are exposed. It often causes the splitting of both male and female genitalia , and the anus is occasionally sealed.Cloacal exstrophy is an extremely rare birth defect, present in only one in 200,000 pregnancies - one...

), or to lose it to accidental trauma in early infancy. In the John/Joan case, John Money claimed successful reassignment at 17 months of age from male to female of a boy whose penis was destroyed during circumcision
Circumcision
Male circumcision is the surgical removal of some or all of the foreskin from the penis. The word "circumcision" comes from Latin and ....

 (though this claim was later shown to be largely fabricated).

The recommended "rules of assignment" and surgery from the late 1960s until the 1990s were roughly:
  • Any XX infant, no matter how virilized, should be raised as a girl to preserve the chance of future fertility. A large, protruding clitoris should be reduced in size with a nerve-sparing recession or reduction rather than simple amputation.
  • Any undervirilized XY infant should be raised as a boy if the penis could be expected to be large enough to stand to urinate
    Urination
    Urination, also known as micturition, voiding, peeing, weeing, pissing, and more rarely, emiction, is the ejection of urine from the urinary bladder through the urethra to the outside of the body. In healthy humans the process of urination is under voluntary control...

     and to insert into a vagina for coitus. If it was too small or too malformed (e.g., cloacal exstrophy
    Cloacal exstrophy
    Cloacal exstrophy is a severe birth defect wherein much of the abdominal organs are exposed. It often causes the splitting of both male and female genitalia , and the anus is occasionally sealed.Cloacal exstrophy is an extremely rare birth defect, present in only one in 200,000 pregnancies - one...

    ) for these functions, it was recommended that the baby be assigned as female, any gonads removed, a vaginal opening surgically constructed, and estrogen
    Estrogen
    Estrogens , oestrogens , or œstrogens, are a group of compounds named for their importance in the estrous cycle of humans and other animals. They are the primary female sex hormones. Natural estrogens are steroid hormones, while some synthetic ones are non-steroidal...

     provided at puberty
    Puberty
    Puberty is the process of physical changes by which a child's body matures into an adult body capable of reproduction, as initiated by hormonal signals from the brain to the gonads; the ovaries in a girl, the testes in a boy...

    .
  • An infant with mixed chromosomes (e.g., mixed gonadal dysgenesis or true hermaphroditism
    True hermaphroditism
    True hermaphroditism is a medical term for an intersex condition in which an individual is born with ovarian and testicular tissue.There may be an ovary on one side and a testis on the other, but more commonly one or both gonads is an ovotestis containing both types of tissue.It is rare—so...

    ) could be raised either way depending on appearance of genitalia and size of phallus.
  • Gender identity is set by 2 years of age and reassignment after that age should not be attempted unless requested by the patient.


These continued to be the most commonly used criteria for assignment until the mid-1990s with one modification. With the recognition in the late 1970s that many cases of micropenis
Micropenis
Micropenis is an unusually small penis. A common criterion is a dorsal erect penile length of at least 2.5 standard deviations smaller than the mean human penis size. The condition is usually recognized shortly after birth...

 could be treated with hormones, female assignment for unambiguous micropenis went from "recommended but uncommonly done" to "rarely" done.

In the last decade a number of factors have led to changes in the recommended criteria for assignment and surgery. These factors have included:
  • Dozens of grown intersex patients complained publicly about unsatisfactory sexual function or incongruent gender identity, and criticized infant surgery for intersex conditions. Some have suggested that assignments be made more tentatively and surgery deferred in acknowledgement of the possibility of a desire to change gender when the child is older (see Re-assignment, below)

  • In 1997, the "rest of" David Reimer
    David Reimer
    David Reimer was a Canadian man who was born as a healthy male, but was sexually reassigned and raised as female after his penis was accidentally destroyed during circumcision. Psychologist John Money oversaw the case and reported the reassignment as successful, and as evidence that gender...

    's story was made public. He was the boy who had lost his penis to a surgical accident at 8 months in 1966, was reassigned from boy to girl at 18 months with further surgery to remove testes and estrogen treatment beginning at age 12. Although John Money
    John Money
    John William Money was a psychologist, sexologist and author, specializing in research into sexual identity and biology of gender...

     had described the reassignment as a success in the 1970s, Reimer went public with his account of continuing to have a male gender identity despite the reassignment to a female sex of rearing. At age 15, Reimer reverted to living as a male. At age 38, he committed suicide.

  • There has been a significant swing in educated opinion back toward the importance of biological factors ("nature") in many aspects of human sexuality.

  • A large proportion of XY infants born with cloacal exstrophy
    Cloacal exstrophy
    Cloacal exstrophy is a severe birth defect wherein much of the abdominal organs are exposed. It often causes the splitting of both male and female genitalia , and the anus is occasionally sealed.Cloacal exstrophy is an extremely rare birth defect, present in only one in 200,000 pregnancies - one...

     and raised as female from early infancy have requested reassignment to male gender in late childhood and adolescence.


Current recommendations for assignment in cases of intersex and other birth defects of the genitalia:
  • Raise nearly all XX
    XY sex-determination system
    The XY sex-determination system is the sex-determination system found in humans, most other mammals, some insects and some plants . In this system, females have two of the same kind of sex chromosome , and are called the homogametic sex. Males have two distinct sex chromosomes , and are called...

     infants with functional ovaries as female.
    • The only rare exception would be completely and unambiguously virilized XX infants with CAH
      Congenital adrenal hyperplasia
      Congenital adrenal hyperplasia refers to any of several autosomal recessive diseases resulting from mutations of genes for enzymes mediating the biochemical steps of production of cortisol from cholesterol by the adrenal glands ....

      , who might be raised as male with genital surgery deferred.
  • Raise most ambiguous XY
    XY sex-determination system
    The XY sex-determination system is the sex-determination system found in humans, most other mammals, some insects and some plants . In this system, females have two of the same kind of sex chromosome , and are called the homogametic sex. Males have two distinct sex chromosomes , and are called...

     infants with testes as male unless the external genitalia are more female than male, marked androgen insensitivity is present, and testes are absent or defective.
    • Raise as male any XY infant with unambiguous micropenis.
    • Raise as male any XY infant with functional testes and normal androgen sensitivity but malformed or absent penis.
  • Raise infants with mixed gonadal tissue, true hermaphroditism, or other chromosomal abnormalities as the sex most consistent with external genitalia, since gonads are usually nonfunctional.
  • Gender identity is set by 1–2 years of age and reassignment after that age should not be attempted unless requested by the patient.


Controversies have continued in this decade over surgical aspects of intersex management, especially indications for surgery and optimal timing, but the revised assignment recommendations have been nearly universally accepted.

Reassignment of sex or gender

Sex reassignment refers to a change in sex and/or gender after an original and presumably definitive assignment in infancy. This event can occur in several circumstances.
  1. An early reassignment may be made to correct a clear error. The most common example of this is when a newborn is assumed to be a boy and assigned as such despite absent testes. If at 1–4 weeks of age it is discovered because of newborn screening, a salt-wasting crisis, or investigation of the cryptorchidism that "he" has ovaries, uterus, an XX karyotype
    Karyotype
    A karyotype is the number and appearance of chromosomes in the nucleus of an eukaryotic cell. The term is also used for the complete set of chromosomes in a species, or an individual organism.p28...

    , and CAH
    Congenital adrenal hyperplasia
    Congenital adrenal hyperplasia refers to any of several autosomal recessive diseases resulting from mutations of genes for enzymes mediating the biochemical steps of production of cortisol from cholesterol by the adrenal glands ....

    , the child is likely to be reassigned as female. When virilization is complete and unambiguous, reassignment may be declined or deferred. Any reassignment after the first month or two is no longer considered an "early reassignment".
  2. There have been cases where a male infant has been reassigned to female at several days, weeks, or months of age because of an irreparable birth defect of the genitalia or loss of the penis to trauma or other accident. This is no longer recommended by most experts in the field because of the publicity surrounding similar failed reassignments which became public in the 1990s, such as that of David Reimer
    David Reimer
    David Reimer was a Canadian man who was born as a healthy male, but was sexually reassigned and raised as female after his penis was accidentally destroyed during circumcision. Psychologist John Money oversaw the case and reported the reassignment as successful, and as evidence that gender...

    .
  3. There have been rare cases where a child with an intersex condition has rejected a sex of rearing, asserted an opposite gender identity, and requested reassignment. Examples of this have occurred in adolescents with several forms of CAH and 5-alpha-reductase deficiency
    5-alpha-reductase deficiency
    5-Alpha-reductase deficiency is an autosomal recessive intersex condition caused by a mutation of the 5-alpha reductase type 2 gene.-Normal function:...

    .
  4. The most common type of reassignment occurs when a child or adult with no detectable intersex condition has the psychology of the opposite sex, claims a different gender identity, and either requests or asserts a new gender. Such a person is described as transgender
    Transgender
    Transgender is a general term applied to a variety of individuals, behaviors, and groups involving tendencies to vary from culturally conventional gender roles....

     or transsexual. Therapy
    Sex reassignment therapy
    Sex reassignment therapy is an umbrella term for all medical procedures regarding sex reassignment of both transgender and intersexual people...

     and/or surgery
    Sex reassignment surgery
    Sex reassignment surgery is a term for the surgical procedures by which a person's physical appearance and function of their existing sexual characteristics are altered to resemble...

     to align their body with their sex identity. This may be preformed in adulthood and, in recent years, adolescents.
  5. One case of reassignment occurred with a pair of male ischiopagus conjoined twins
    Conjoined twins
    Conjoined twins are identical twins whose bodies are joined in utero. A rare phenomenon, the occurrence is estimated to range from 1 in 50,000 births to 1 in 100,000 births, with a somewhat higher incidence in Southwest Asia and Africa. Approximately half are stillborn, and a smaller fraction of...

     who shared one set of male genitalia. On surgical separation, one twin received the male genitalia and the other twin was surgically feminized.

See also

  • Sexual differentiation
    Sexual differentiation
    Sexual differentiation is the process of development of the differences between males and females from an undifferentiated zygote...

  • Intersexual
  • List of transgender-related topics
  • History of intersex surgery
    History of intersex surgery
    The history of intersex surgery is intertwined with the development of the specialities of pediatric surgery, pediatric urology, and pediatric endocrinology, with our increasingly refined understanding of sexual differentiation, with the development of political advocacy groups united by a sexual...

     for a more detailed history of the evolution of medical management of intersex conditions, with a more extensive list of references.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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