Typical criteria of sex
its more than chromosomes
Professor Julie A. Greenberg, writing in the Summer 1999 issue of the Arizona Law Review, states:
"Medical experts recognize that many factors contribute to the determination of an individual's sex. According to medical professionals, the typical criteria of sex include:
1. Genetic or chromosomal sex--XY or XX;
2. Gonadal sex (reproductive sex glands)--testes or ovaries;
3. Internal morphologic sex (determined after three months gestation)--seminal vesicles/prostrate [sic] or vagina/uterus/fallopian tubes;
4. External morphologic sex (genitalia)--penis/scrotum or clitoris/labia;
5. Hormonal sex--androgens or estrogens;
6. Phenotypic sex (secondary sexual features)--facial and chest hair or breasts;
7. Assigned sex and gender of rearing; and
8. Sexual identity. "For most people, these factors are all congruent, and one's status as a man or woman is uncontroversial. For intersexuals, some of these factors may be incongruent, or an ambiguity within a factor may exist.
"'The assumption is that there are two separate roads, one leading from XY chromosomes at conception to manhood, the other from XX chromosomes at conception to womanhood. The fact is that there are not two roads, but one road with a number of forks that turn in the male or female direction. Most of us turn in the same direction at each fork.'
"The bodies of the millions of intersexed people have taken a combination of male and female forks and have followed the road less traveled. These individuals have noncongruent sexual attributes. For these individuals, the law must determine which of the eight sexual factors will determine their sex and whether any one factor should be dispositive for all legal purposes.
"Because the law has typically looked to biology and the medical community for guidance in determining how an individual's sex should be legally established, the complex nature of sexual differentiation must be understood. . . .
"A. Sexual Differentiation--The Typical Path
"During the first seven weeks after conception, all human embryos are sexually undifferentiated. At seven weeks, the embryonic reproductive system consists of a pair of gonads that can grow into either ovaries (female) or testes (male). The genital ridge that exists at this point can develop either into a clitoris and labia (female) or a penis and a scrotum (male). Two primordial duct systems also exist at this stage. The female ducts are called Mullerian ducts and develop into the uterus, fallopian tubes and the upper part of the vagina if the fetus follows a female path. The male ducts are called Wolffian ducts and are the precursors of the seminal vesicles, vas deferens and epididymis.
"At eight weeks, the fetus typically begins to follow one sex path. If the fetus has one X and one Y chromosome (46XY), it will start down the male path. At eight weeks, a 'master switch' on the Y chromosome, called the testis-determining factor, signals the embryonic gonads to form into testes. The testes begin to produce male hormones. These male hormones prompt the gonads and genitalia to develop male features. Additionally, the testes produce a substance called Mullerian inhibiting factor that causes the female Mullerian ducts to atrophy and be absorbed by the body, so that a female reproductive system is not created.
"Because the typical female fetus is 46XX and does not have a Y chromosome, the master switch that leads to the development of male organs is not turned on. The fetus continues on what is considered the default path and in the thirteenth week the gonads start to transform into ovaries. Because no testes exist to produce male hormones, the remainder of the sexual system develops along a female path. During this time, the Wolffian (male) ducts shrivel up. In other words, unless the body is triggered by hormonal production to follow the male path, the fetus will normally develop as a female. Therefore, although chromosomes generally control the hormones that are produced, it is actually the hormones that directly affect sexual development.
. . . .
"B. Sexual Differentiation--Intersexuals: The Paths Less Followed
"Two circumstances may lead to an intersexual condition: (1) failure to meet the typical criteria within any one factor; or (2) one or more factors may be incongruent with the other factors.
"1. Ambiguity Within a Factor
"a. Chromosomal Ambiguity--Certain individuals have chromosomes that differ from the typical pattern of either XY or XX. Doctors have discovered people with a variety of combinations including: XXX, XXY, XXXY, XYY, XYYY, XYYYY, and XO.
"b. Gonadal Ambiguity--Some intersexuals do not have typical ovaries or testes. Instead, they have 'streak' gonads that do not appear to function as either ovaries or testes. Others have ovotestes, a combination of both male and female gonads. Still others have one ovary and one testis.
"c. External Morphologic Sex--Some individuals' external genitalia are neither clearly male nor clearly female. In addition, some women have clitoral hypertrophy, a clitoris that is larger than the typical clitoris, may more closely resemble a penis, and is sometimes accompanied by an internal vagina.
"d. Internal Morphologic Sex--Some individuals have incomplete internal sex organs or a complete absence of an internal sex organ. In addition, some individuals are born with a combination of male and female internal organs.
"e. Hormonal Sex--The male hormones are referred to as androgens. The female hormones are estrogen and progesterone. Although they are referred to as male and female hormones, all human sex hormones are shared by men and women. Typically, men and women have hormones of each type, but the levels of production and reception of each hormone are highly variable among all individuals. Different medical disorders further influence levels of hormone production and/or reception.
"f. Phenotypic Sex--Individuals may have a variety of combinations of incongruent phenotypic characteristics. In other words, an individual may have characteristics that are typically associated with a male (heavy facial hair) and characteristics that are typically associated with a female (developed breasts).
"g. Assigned Sex/Gender of Rearing--Although it occurs rarely, some parents have raised their child as a gender other than the sex that was assigned by the medical attendant at birth. In addition, in some circumstances, doctors have recommended that a child be raised as the sex different from the one assigned at birth.
"h. Sexual Identity--Sexual identity refers to how individuals would identify themselves; gender identity refers to how society would identify an individual. Some individuals do not consider themselves to be either male or female; they identify themselves as a third sex.
"2. Ambiguity Among Factors
"Some individuals have an incongruence among the eight factors due to a sexual differentiation disorder. In other words, some factors may be clearly male, some may be clearly female, and others may be a mixture of male and female. Incongruity among factors can result from a number of disorders and circumstances including:
a. Chromosomal sex disorders;
b. Gonadal sex disorders;
c. Internal organ anomalies;
d. External organ anomalies;
e. Hormonal disorders;
f. Gender identity disorders; and g. Surgical creation of an intersexed condition.
"These conditions are described in detail below . . . .
"a. Chromosomal Sex Disorders
"Klinefelter Syndrome
"Approximately one in 500 to 1000 'males' is affected by Klinefelter Syndrome, a condition in which a mostly phenotypic male does not fall neatly into the XY chromosome complement. Individuals with Klinefelter Syndrome will typically have two or more X chromosomes. The testes, and often the penis, are smaller than in unaffected XY males.
"A diagnosis of Klinefelter Syndrome is typically not made before puberty because no easily identifiable sign exists prior to the onset of puberty. The swelling of the breasts (gynecomastia) that occurs in adolescence is typically the first sign of the existence of this intersexual condition. Most individuals with Klinefelter Syndrome report a male psychosexual orientation. Many take supplemental testosterone, which further results in a male phenotype (e.g. facial hair).
"Turner Syndrome
"Disorders of chromosomal sex also appear in phenotypic females. Turner Syndrome is a condition that affects approximately one in 5000 newborn females. Individuals with Turner Syndrome will typically have an XO chromosomal pattern, not falling neatly into the XX, XY binary system. Individuals with Turner Syndrome typically have bilateral 'streak' gonads (unformed and non-functioning gonads) instead of clearly defined ovaries or testes. The absence of complete ovaries or testes in-utero means that the fetus has little exposure to either female or male hormones. In the absence of male hormones, the fetus will follow the female path.
"Individuals with Turner Syndrome are typically shorter than XX females. They have female appearing genitalia, but little breast development in the absence of exogenous estrogen administration.
"b. Gonadal Sex Disorders--Swyer Syndrome
"Pure gonadal dysgenesis is a condition sometimes referred to as Swyer Syndrome. This syndrome is similar to Turner Syndrome in that individuals with this syndrome will have only streak gonads. In contrast to Turner Syndrome, in which a chromosome is missing (XO), individuals with Swyer Syndrome have XY (male) chromosomes. Although Swyer Syndrome individuals have a Y chromosome, the chromosome may be missing the sex-determining segment. Without this segment, the embryo cannot develop testes and as a result, the masculinizing hormones are also missing. In the absence of the masculinizing hormones, the fetus will take the 'default' female path and will develop a uterus but will not have any ovaries.
"This condition is not apparent at birth and the child will be raised as a girl. The syndrome is generally diagnosed at puberty when the absence of a menstruation and breast enlargement causes suspicion.
"c. Internal Organ Anomalies--Persistent Mullerian Duct Syndrome
"Individuals with Persistent Mullerian Duct Syndrome have the internal organs typical of males as well as females. These individuals have a male chromosomal pattern (XY) and therefore develop testes which secrete androgen but for some reason fail to secrete anti-Mullerian hormones. The androgens cause the fetus to follow the male path and develop the external appearance and internal organs of a male. However, fallopian tubes and a uterus are also formed because the anti-Mullerian hormones are not acting to stop this development. This condition is generally not diagnosed at birth. Individuals with this syndrome are reared as males and have a male identity.
"d. External Organ Anomalies: Hermaphroditism
"Individuals who have ambiguous external genitalia (neither clearly male nor female) are commonly referred to as hermaphrodites. Hermaphrodites are often classified into three categories: true hermaphrodites, male pseudo-hermaphrodites, and female pseudo-hermaphrodites. A 'true hermaphrodite' has some ovarian and some testicular tissue. So-called 'true hermaphrodites' have either one ovary and one testis, two ovotestes (a combination of an ovary and testis in a single gonad) or some combination thereof (e.g. one ovotestes and one ovary). True hermaphroditic conditions are more rare than many of the other intersex conditions described in this section. A male pseudo-hermaphrodite has testes and no ovaries but some aspect of female genitalia. A female pseudo-hermaphrodite has ovaries and no testes and some aspect of male genitalia.
"A variety of disorders can lead to hermaphroditic conditions. Hermaphroditic conditions are named according to their etiology (e.g. Partial Androgen Insensitivity Syndrome ['PAIS'] or Congenital Adrenal Hyperplasia ['CAH']) unless the etiology of the condition remains unknown.
"True hermaphroditism is rare and the exact incidence is unknown. The chromosome count may vary but is predominantly 46XX.
"e. Hormonal Disorders
"Androgen Insensitivity Syndrome
"Androgen Insensitivity Syndrome ('AIS') affects approximately 1 out of every 20,000 genetic males. AIS can be either complete ("CAIS") or partial (PAIS). Individuals with AIS are born with XY chromosomes and normally-functioning testes, which would otherwise suggest a normal male fetus. Individuals with CAIS, however, have a receptor defect and are unable to process the androgens produced by the testes.
"Because the body cannot process the androgens, the fetus will follow the default path of female development. External female genitalia will form. No internal reproductive organs will form because the Mullerian inhibiting factor produced by the testes will inhibit the growth of the uterus and fallopian tubes. The vagina will be shorter than in the typical woman (or may only be a dimple) and will end blindly because there are no female internal reproductive organs with which to connect.
"Unlike several other intersex conditions, individuals with CAIS almost always are identified as 'normal' females at birth because externally they are indistinguishable from XX females. The disorder is sometimes diagnosed in infancy because of inguinal hernias that contain the testes. Often, however, CAIS is not diagnosed until after the onset of puberty as a result of a failure to menstruate. At puberty, breasts will form because of the estrogen that is produced by the testes. Until puberty, many CAIS women have no inkling that they are other than normal XX women.
"In PAIS, an XY individual with testes will be partially receptive to androgens. Unlike individuals with CAIS, individuals with PAIS may fall anywhere along a spectrum from an almost completely male external appearance and male sexual identity to a completely female external appearance and female sexual identity. The degree to which the individual has male features depends upon the degree to which the receptors are able to process the male hormones the testes produce.
"The external phenotype of PAIS individuals will initially be determined by the degree of androgen reception in the body. Thus, a PAIS individual may have genitalia resembling either a clitoris or a penis, the labia may be fused, and during adolescence there may be breast development due to the conversion of testosterone produced by the gonads to estradiol, an estrogen compound.
"5-Alpha-Reductase Deficiency
"This condition is similar to the androgen resistance syndromes. Individuals with 5-Alpha-Reductase Deficiency have XY chromosomes and testes but appear phenotypically female at birth. This condition results from the body's failure to convert testosterone to dihydrotestosterone, the more powerful form of androgen responsible for the development of male external genitalia. Despite a female appearance during childhood, by the onset of puberty, the body will masculinize. The testes descend, the voice deepens, muscle mass substantially increases, and a 'functional' penis that is capable of ejaculating develops from what was thought to be the clitoris. The prostate, however, remains small and beard growth is scanty. Although the individual is typically raised as a girl, at puberty, psychosexual orientation typically becomes male. In other words, virilization will occur at puberty in the absence of medical intervention.
"5-Alpha-Reductase Deficiency is an inheritable condition, and has resulted in a large group of affected individuals in some communities in the Dominican Republic. In some cases, a diagnosis is made in early puberty, male external development is arrested, and the individual will take exogenous female hormones to simulate a female puberty. In these cases, the individual will often have a female sexual identity. Other individuals with 5-Alpha-Reductase Deficiency will develop a masculine appearance in conformity with their genotype and will also develop a male psychosexual identification.
"Congenital Adrenal Hyperplasia
"Some individuals with XX chromosomes, ovaries, and other female internal structures have a more masculinized external appearance and/or demeanor due to an abundance of androgen production in-utero. Typical of this category is 21-Hydroxylase Deficiency Congenital Adrenal Hyperplasia ('CAH'). It occurs in approximately one out of 5000 to 15,000 births.
"Both the chromosomes and gonads of CAH individuals are indistinguishable from unaffected females. The genitals, however, may be ambiguous and may more closely resemble male genitalia.
"Some CAH individuals have been identified as males at birth and are reared as boys despite the presence of XX chromosomes and ovaries. In other cases, the masculinization of prenatal life is interrupted at birth, and the child is surgically and hormonally treated and reared as a girl. These girls often have characteristics that are popularly stereotyped as masculine. In addition, many CAH individuals identify themselves as lesbians.
"Progestin-Induced Virilization
"Similar to CAH is Progestin-Induced Virilization ('PIV'), which results from an abundance of male hormones in an otherwise normal XX female. PIV is caused by exposure in-utero to progestin that has been taken by the mother during pregnancy. Like individuals with CAH, PIV women will frequently have clitoral hypertrophy. In all other respects, however, they have completely female gonads.
"f. Gender Identity Disorder
"Some individuals may be seemingly harmonious in all of the first six factors, but do not identify themselves with the sex associated with these factors. These individuals may be said to have gender dysphoria or gender identity disorder ('GID'). Often these individuals are called transsexuals. Science has yet to definitely isolate a biological common denominator that causes these individuals to feel transgendered. A recent study, however, has determined that a section of the brain area that is essential for sexual behavior is larger in men than in women and that the brain structure of genetically male transsexuals is more similar to female brains than to male brains. Some transgendered individuals choose to undergo hormonal treatment and/or surgery so that their bodies comport with their sexual identity while other transsexuals do not choose to undergo such treatment.
"Transsexualism is not necessarily related to sexual orientation. Some transsexuals identify themselves as gays or lesbians while others identify themselves as heterosexuals. In other words, a male-to-female transsexual who has undergone surgery to acquire female genitalia may still prefer to have sex with another female, and a female-to-male transsexual may still prefer to have sex with another male.
"g. Surgical Creation of an Intersexed Condition
"In addition to cases in which intersexed individuals may be assigned a sex that does not comport with their own sexual identity, some persons have had their sexual features altered either accidentally or purposefully. For instance, some individuals have had their penises removed at a young age because they were mistakenly identified as females and the penis was considered an oversized clitoris that required reduction. Although these cases are rare, they are illustrative of the complex nature of sexual identity.
"The most famous surgical alteration case involves a male whose penis was accidentally ablated when he was eight months old. The doctors recommended that his genitals be reconstructed to have a female appearance and that he be raised as a girl even though all other sexual factors were congruent and were male. The doctors also recommended that his 'history' as a male be hidden from him.
"This surgical alteration case made headlines in 1973. Because the doctors involved in the surgical alteration reported that the child and the parents had successfully adapted to the sex/gender alteration, sociology, psychology, and women's study texts were rewritten to argue, 'This dramatic case . . . provides strong support . . . that conventional patterns of masculine and feminine behavior can be altered. It also casts doubt on the theory that major sex differences, psychological as well as anatomical, are immutably set by the genes at conception.'
"For more than twenty years, the scientific literature continued to report that the surgical alteration was successful and the child's sexual identity was female. This case made headlines again in 1997 when Milton Diamond and Keith Sigmundson reported in the Archives of Pediatric & Adolescent Medicine that the boy who was turned into a girl was now living as a man.
"According to the Diamond and Sigmundson report, John (a pseudonym) had always thought of himself as different from other girls. As a child, he preferred 'boy' type toys and preferred to mimic his father's rather than his mother's behavior. He also preferred to urinate in a standing position although he had no penis. Because of the cognitive dissonance, Joan (a pseudonym used by the authors to describe John while he lived a female life) often had thoughts of suicide.
"At twelve, Joan was put on an estrogen regimen. She rebelled against the regimen and often refused to take the medication. At fourteen, Joan confessed to a doctor that she had suspected that she was a boy since second grade. At that point, the doctors agreed with Joan that she should be remasculinized and become John once more. At age fourteen, Joan/John returned to living as a male. He received male hormone shots and a mastectomy. He underwent surgery to reconstruct a phallus at ages fifteen and sixteen. John was eventually accepted as a boy by his peers. He is now married and helping to raise his wife's children.
"John was not born an intersexual. He became an intersexual when doctors removed his penis, constructed external female genitalia and administered female hormones. Despite this intervention, John always felt that he was not a female.
"In another recently reported similar case, a child's penis was severely damaged during a circumcision that was performed when the child was two months old. A decision was made to 'turn' the child into a girl. At seven months, surgery was performed to remove the remainder of the male genitalia and from that point on the child was raised as a girl. She was interviewed by a psychiatrist at ages sixteen and twenty-six. The results of these interviews indicate that she self identifies as a bi-sexual female whose recreational and occupational interests are more typically identified with males.
"The significance of these two reports is that they exemplify the difficulty law and medicine must confront in defining sex. At birth, these infants' sex factors were congruent and were male. After the original intervention, they were turned into intersexuals but were treated by society as if they were females. They had male chromosomes, ambiguous genitalia, and female gender assignment. As adults, one person self-identifies as a heterosexual male while the other self-identifies as a bi-sexual female.
"These studies and other reports about intersexuals have forced the medical and psychiatric communities to question their long-held beliefs about sex and sexual identity. Just as current scientific studies have caused the scientific communities to question their beliefs about sex and sexual identity, the legal community must question its long-held assumptions about the legal definitions of sex, gender, male, and female." Greenberg, Defining Male and Female: Intersexuality and the Collision Between Law and Biology, 41 Ariz. L. Rev. 265, 278-92 (1992).
