The categories “man and woman” and “male and female” do not capture every person.

“Masculine and feminine” also fail to describe every person’s gender.

Understanding Biological Sex

The biology of sex starts with a discussion ofchromosomes, hormones, and anatomy.

Blocks representing biological sexes

Gerardo Carnero / Getty Images

The Role of Sex Chromosomes

The two types of sex chromosomes are X and Y.

Having two distinct sexes (male and female) creates abinary.

When all of an individual’s sex characteristics correspond to one biological sex, they are described asendosex.

Chromosomal Variations

However, researchers have learned that biological sex isn’t always that simple.

Other times, though, it results in someone who’s endosex.

Some of these combinations don’t cause medical problems and simply represent normal genetic differences.

Other combinations cause medical problems which are called disorders of sexual differentiation.

Everyone has hormones that are associated with sex characteristics.

People assigned male at birth have higher levels of certain hormones, liketestosterone, in their bodies.

People assigned female at birth tend to produce moreestrogen.

However, everyone has both testosterone and estrogen present in their body regardless of their sex assigned at birth.

Exposure tosex hormoneshelps guide both fetal and adolescent development of sex characteristics.

That can lead to an intersex baby.

The Role of Anatomy

Your anatomy is your bodily structure.

That includes your genitalia.

The sex noted on your birth certificate is a form of medical classification.

It reflects healthcare providers' interpretations of the genitalia they saw when you were born.

This sex would then be reported on the child’s birth certificate.

It is separate from biological sex.

Gender identityis someone’s personal understanding and explanation of their gender.

People who fall into any of these categories may refer to themselves as transgender or trans, as well.

However, not all of them do.

It is the sex they wereassigned at birth.

Once someone has made their gender known, you should use the appropriate pronouns.

A pronoun is a word used in place of a name or names.

Some have gender-neutral pronouns: they/them/theirs.

This is considered grammatically correct as these pronouns have both single and plural usage in the English language.

Mashed-up terms like “he-she” or “shemale” are highly offensive as well.

Calling or referring to them by that name iscalled deadnaming.

A trans person’s chosen name is the correct name to use when referring to them.

Using a trans person’s correct name is associated with lower suicidality and depressive symptoms among trans youth.

What Is Gender Expression?

In addition to gender identity, people also havegender expression.

That describes the gendered ways someone presents themselves to the world.

Your gender expression may or may not reflect your gender identity.

Many circumstances may prevent someone from presenting in a way that matches their true gender.

This includes young people whose parents don’t allow them to express a certain way.

Gender Identity and Sexual Orientation

Gender identity is completely separate from sexual orientation.

For instance, a trans woman who is attracted to men is considered straight.

A trans man who is attracted to men is considered gay.

Gender-Affirming Care

Some trans people choose to seek out gender-affirmingmedical treatmentorsurgical proceduresto further express their true gender.

Hormone therapy may cause a shift in sexual orientation, but this does not always occur.

Not Everyone Transitions

Not everyone who’s trans makes a medicaltransition.

Others may never make medical changes to their bodies.

This may be due to financial, social, or familial pressures.

It could be because they have an external medical issue that is an obstacle to medical transition.

Others simply don’t feel that medical transition is necessary.

Trans people should not be judged whether they medically transition or not.

Lack of medical transition does not invalidate someone’s gender.

The goal was to “normalize” the appearance of the child’s genitalia.

Beliefs are changing, though, and activists are calling for an end to these practices.

Advocate for single-stall, gender-neutral bathrooms to ensure safety for this population.

Summary

Sex is biological and based on chromosomes, hormones, and anatomy.

Gender identity is your personal interpretation of your gender.

Gender identity doesn’t dictate sexual orientation.

Gender expression is how you present yourself to the world.

People whose sex and gender do not align with social and cultural norms are transgender.

Many terms exist that mean different things about trans identity, including agender, genderfluid, and nonbinary.

People whose sex and gender align with social and cultural norms are cisgender.

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