What Is Intersex?

Differences In Sexual Development

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Intersex is a general term used to describe anyone with physical or biological sex characteristics that are more diverse than the traditional definitions of male or female bodies.

Sex is not binary, meaning there are more than two options. Intersex can involve variations in sex chromosomes, hormonal patterns, genitals, or the internal reproductive system.

These variations, which are sometimes referred to as differences in sexual development or disorders of sexual development (DSDs), may be apparent at birth or may not be recognized until later in life, such as during puberty or when trying to have a child.

Sometimes a person is never aware that they have a variation.

This article will explore what it means to be intersex and will give some examples of variations.

Mother holding her baby hand
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There are many possible variations in sex chromosomes, hormones, or anatomy that can be inherited from one or both parents or occur due to spontaneous changes in genes.

Sex chromosomes are the X and Y chromosomes that participate in gender assignment, which is typically XY in males and XX in female. However, there can be variations in these chromosomes, such as additional X chromosomes, that may or may not affect anatomy.

Some people's bodies respond differently to the messages of the sex hormones or do not produce enough hormones, affecting sexual development.

In other instances, prenatal exposures to hormonal medications or other unknown sources may affect sexual characteristics.


Intersex characteristics can be due to many factors and can be inherited or due to random changes in genes.

How Common Is It?

There is limited tracking, but it's estimated that between 1% and 2% of people are born with intersex variations, and about one in 2,000 babies have variations in genitals.

Klinefelter syndrome, which is sometimes referred to as XXY syndrome, is one of the most common chromosomal variations. It's when a newborn male is born with an extra X chromosome and it's estimated that about one in 500 to 1,000 males have an extra X chromosome.

Because medical professionals are not consistently well trained in understanding intersex issues, they do not always provide the best advice for the parents of a newborn with variations in characteristics.

Genital surgeries should generally not be done in infancy unless there is an urgent medical issue—such as a blockage that prevents an infant from urinating—and should be delayed so that individuals can decide for themselves.


There are at least 60 groups of conditions that are considered intersex, or differences in sexual development.

Although, even among a particular genetic condition there can be a wide range of variations in anatomy that are possible.

There are many medical terms for intersex variations, or DSDs, and some examples include Klinefelter's syndrome, androgen insensitivity, and congenital adrenal hyperplasia.

Klinefelter Syndrome

If there is an additional X for XXY it's referred to as Klinefelter syndrome or sometimes XXY syndrome.

Those with Klinefelter syndrome may have decreased testosterone production, which is called primary hypogonadism, and they may have a low sperm count that leads to infertility, meaning they are unable to have children.

They also tend to be tall. In some cases there is a urethral opening for the penis that's not at the tip, which is called hypospadias. There may be a small penis, known as a micropenis. It can also lead to enlarged breast tissue that's known as gynecomastia.

Most individuals whose chromosomes are XXY are unaware they have a variation and researchers estimate that only about 25% of those whose chromosomes are XXY ever get diagnosed. Among those diagnosed, it tends to be adulthood. The average age people get diagnosed is in their 30s.

Androgen Insensitivity

Androgen insensitivity is an inherited condition in which your body has a complete or partial inability to respond to testosterone and other androgens, which are hormones that affect sexual development.

Those with androgen insensitivity have the XY chromosomes that is designated male but may have female external genitals or ambiguous genitals that are not clearly male or female.

People with complete androgen insensitivity, meaning their body does not respond to androgens, are typically born with a vulva and a clitoris but no uterus. They also have undescended testes, which means they are internal, and they may have a partial or complete vagina.

Partial androgen insensitivity, which means the body has a limited ability to respond to androgens, can lead to many different variations.

People born with partial androgen insensitivity may appear to have a larger than usual clitoris, known as clitoromegaly, or a micropenis. There may be a urethral opening along the penis rather than at the tip.

Androgens trigger the growth of pubic and underarm hair during puberty, so individuals with androgen insensitivity may have very little or no pubic and underarm hair at puberty.

Congenital Adrenal Hyperplasia

Congenital Adrenal Hyperplasia (CAH) is an inherited condition that affects the adrenal glands that make hormones. CAH can throw these hormones off balance.

Those with congenital adrenal hyperplasia lack one of the key enzyme needed to make certain hormones. This can lead to inadequate production of certain hormones, such as cortisol, and excessive production of androgens.

In individuals with the XX chromosomes designated female, CAH may lead to a large clitoris and labia that's fused so there isn't a vaginal opening or ambiguous external genitals. Internally, there are ovaries, a uterus, and a full or partial vagina.

Congenital adrenal hyperplasia can lead to early puberty, fast body growth, and premature completion of growth that leads to short height.


It's estimated that about 1% to 2% of individuals are born with intersex variations.

There are at least 60 groups of conditions that are considered differences in sexual development, but even among the same group or condition there can be a lot of variation in characteristics.

What Is the Impact of Being Intersex?

There is a wide variation in personal experiences and individual feelings about being intersex.

Intersex is not the same as gender identity. An intersex individual may identify as female, male, or nonbinary regardless of their anatomy.

Although rare, variations in sex characteristics can sometimes indicate underlying medical concerns, such as an increased risk of cancer after puberty. If you or your child has any known variations in characteristics, it is important to make your doctor aware of them.


As a sexual minority, people who are intersex may be subjected to shunning, ridicule, social exclusion or other negative behavior from bigoted people or those who simply do not understand what it means to be intersex.

Unfortunately, for far too long, people with intersex characteristics, previously called the derisive and stigmatizing term hermaphrodites, have been the butt of jokes.

Discrimination can even occur in medical offices and in guidance about possible surgeries or in responses from family and friends.

Due to these issues, those who are intersex may be at increased risk of substance abuse and addiction problems.


Personal experiences and feelings about being intersex vary widely from person to person. Due to discrimination and shaming, individuals with variations may have an increased risk of substance abuse and addiction.


Intersex is an umbrella term for any variations in sexual development and there are many diverse ways to be intersex.

There may be variations in sex chromosomes or genetic changes that affect production or response to hormones.

Sometimes intersex characteristics are identified at birth. Other times they are not found until later in life or the person may never become aware of them.

Genital surgeries should generally not be done in infancy unless there is an urgent medical issue.

A Word From Verywell

Awareness is growing about the range of diversity in sexual anatomy and traits, yet there can still be many challenges for individuals who are intersex and their families.

It can sometimes help to connect with a support group and to share your experiences. InterAct, an organization that advocates for intersex youth, has resources and maintains a list of support and advocacy groups.

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6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. InterAct. Intersex FAQ.

  2. National Center for Advancing Translational Sciences. Klinefelter syndrome. Updated October 13, 2015.

  3. American Academy of Pediatrics. Explaining disorders of sexual development and intersexuality. Updated November 21, 2015.

  4. Groth KA, Skakkebæk A, Høst C, Gravholt CH, Bojesen A. Klinefelter syndrome—a clinical updateThe Journal of Clinical Endocrinology & Metabolism. 2013;98(1):20-30. doi:10.1210/jc.2012-2382

  5. National Organization for Rare Disorders. Congenital adrenal hyperplasia.

  6. Substance Abuse and Mental Health Services Administration. Identifying mental health and substance use problems of children and adolescents: a guide for child-serving organizations. Updated in 2012.