1. Intersexuality: when biology comes in more than two categories

2. What is Intersexuality?
Intersexuality is a term which groups together a huge number of different physical conditions.
What do these conditions have in common? They all lead to an individual with unusual sex characteristics, an individual who is physically different from the usual biological definitions of “male” and “female.”
A baby with unusual looking genitals may be diagnosed as intersex at birth. Other times, physical differences are not clear until puberty.
Intersex children are often diagnosed with a “disorder of sex development.” According to the Handbook for Parents, this is “[w]hen a less-common path of sex development is taken.” So, intersex individuals are those who have developed in an uncommon way.

3. Intersexuality in Context: What we mean by “male” and “female”
Biological definitions of male and female are complicated. They include chromosomes, primary sex characteristics, secondary sex characteristics, and hormones.
In general, a male human has XY chromosomes, a male reproductive system and genitals, and male secondary sex characteristics which develop at puberty
-Some examples of secondary sex characteristics are facial hair and a deeper voice
A female human has XX chromosomes, female reproductive system and genitals, and female secondary sex characteristics which develop at puberty.
-Some examples of secondary sex characteristics are breasts and menstruation
So, any time these many traits don't match up in a person that person may be intersex.

4. Is Intersexuality Normal?
Intersexuality is rare, though there are different estimates of how rare
One figure (used in the Clinical Guidelines for the Management of Disorders of Sex Development in Childhood) is 1 in 1,500
In some populations, however, certain kinds of intersexuality are more common
What do you think? Can something very unusual still be normal? And if it isn't normal, does that make it bad?

5. What intersexuality is not
Intersex people have bodies which don’t fit neatly into the biological categories of “male” or “female.”
This doesn’t mean that they are not boys or girls, like you, or men and women, like your teachers and parents.
Some intersex children are boys, and some are girls, while some don't feel like they are either
some are raised knowing their bodies are somehow different, others don’t find out until puberty or later
Think about what makes you a boy or girl: is it only your body? Most people consider themselves boys or girls, men or women, because of what they like to do, how they like to see themselves, and how other people see them.

6. What kinds of intersexuality are there?
The term “intersex” lumps together many, many different conditions.
Chromosomal: intersex individuals may have XX chromosomes with a masculine-seeming body, or XY chromosomes with a feminine- seeming body. They may also haveother combinations of chromosomes, such as XXY or XXX
Hormonal: many intersex individuals do not process hormones such as testosterone, estrogen or progesterone in the usual way. These hormones are part of how the body develops, so their bodies then develop differently.
Internal: some few intersex individuals possess both testicular and ovarian tissues. In other words, their internal reproductive systems are a mix of male and female.

7. Why haven’t I heard of this before?
As you now know, intersexuality is rare, which is one reason it isn’t often discussed.
Human biology is very complicated, and is often first taught in a simplified form so that students can understand better.
Many people– teachers included– haven’t been taught much about intersexuality, so they aren’t sure how to address it themselves.
Variation, especially sexual variation, can make people uncomfortable.
All of these factors contribute to a silence about intersexuality

8. Any further questions. Sources: Handbook for Parents. DSD Guidelines
Any further questions? Sources: Handbook for Parents. DSD Guidelines. Consortium on the Management of Disorders of Sex Development. Intersex Society of North America. March 25, Roughgarden, Joan. Evolution’s Rainbow: Diversity, Gender and Sexuality in Nature and People. Berkley: University of California Press, 2004.