What is intersex? Definition, causes and types

Until a few years ago, intersex was considered a disorder, that is, the fact of have intermediate sexual characteristics between those that are typical in males and those that are typical in women.

Nowadays the conception of what intersex is is changing as knowledge of human biology expands and awareness of sex and gender diversity increases.

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What is intersex?

The term "intersex" refers to a series of variations in the organs and sexual characteristics, both at an anatomical and genetic level, which make the person have feminine and masculine characteristics simultaneously. These variations can affect chromosomes, hormones, genitalia, and / or secondary sexual traits, such as the distribution of muscles and fat.

The result of the variations that intersexuality produces is the ambiguity of the sexual anatomy or the discrepancy between the genotype and the phenotype. In summary, we can say that intersex people are those born without all the typically female or male physical traits. In addition, since this does not have to be manifested externally but can also occur only in the genes,

not all intersex people know they are.

From the biological sciences, intersexuality is currently conceived as a set of disorders or variations in sexual development. The second conception, less stigmatizing for intersex people, is becoming more and more general.

Although in many cases it has been medicalized, the truth is that intersex is not usually a danger to survival, although in some cases it does carry a risk of pain and infertility and can cause discomfort with regard to identity sexual.

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Synonym for "hermaphrodite"?

Previously intersex people were known as "hermaphrodites" but today this term is considered derogatory: hermaphroditism consists of the presence simultaneous occurrence of male and female reproductive organs that occurs in some species of animals and plants.

In ancient and medieval Europe people who had ambiguous sexual characteristics were considered hermaphrodites. The law of these societies stated that they should be considered men or women based on the predominant external features. To a large extent, this conception has been maintained to this day.

During the 20th century, the term “intersexuality”, coined by geneticist Richard Golschmidt in 1917, replaced “hermaphroditism” in this type of case. Medical advances during the past century allowed surgical and hormonal interventions will become popular to alter the anatomy of intersex people so that their bodies were more like the prototype of a male or female.

However, the dubious efficacy and risks of these treatments, which are usually practiced in an unsuitable way consensual in minors, have contributed to the emergence of movements that defend the rights of people intersex.

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Causes and types of intersex

There are many possible causes of intersex that cause different variations in genotype and phenotype. These causes can be divided into four main categories based on their most defining characteristics.

1. 46, XX Intersex (with virilization)

In these cases, the person's chromosomes correspond to those that are typical in women, but their external genitalia are those of a male. Even if in intersex 46, XX the person has a uterus, Exposure to elevated levels of male hormones during fetal development, produced by several possible causes, causes the clitoris and labia to develop like a penis.

The most common cause of this type of intersex is congenital adrenal hyperplasia, consisting of defects in the adrenal glands that cause excessive secretion of androgens, as well as deficiency of cortisol and other hormones. This alteration can influence menstruation and hair growth, but in severe cases it can also affect heart rate or blood levels of sodium and potassium.

The presence of ovarian tumors and the mother's consumption of male hormones during pregnancy can also cause intersex with virilization.

2. 46, XY intersex (with undervirilization)

46, XY intersex consists of the presence of male chromosomes and female or ambiguous external genitalia. In this type of intersex, the normal development of the male phenotype from the inhibition of female characteristics is not completed.

The most common cause of intersex with undervirilization is androgen insensitivity syndrome; in these cases the organism is resistant to male hormones, necessary for the development of the gonads and the rest of the male's sexual characteristics.

Malformations in the testicles and insufficient testosterone production are also frequent causes of 46, XY intersex.

3. True gonadal intersex

This type of intersex occurs when the person has both ovaries and testes simultaneously, either complete or incomplete. These variations were formerly known as "true hermaphroditism", as opposed to the terms "Female pseudohermaphroditism" and "male pseudohermaphroditism" that were used for XX intersex and XY, respectively.

In true gonadal intersex, the external genitalia can be male, female, or intermediate, and XX, XY, or both chromosomes can be present at the same time. The cause of these variations is unknown.

4. Complex or indeterminate intersex

We speak of complex or indeterminate intersex when sexual development is altered no inconsistency between genotype and phenotype. Among other aspects, sex hormones or the number of chromosomes may be affected.

For example, cases in which there are two X chromosomes (47, XXY or 47, XXX) and in which there is only one X chromosome (45, XO) would be included in this category.