Most people learn in high school biology that if a child is born with an XY combination, he is a boy, and if a child is born with an XX, she is a girl.

In reality, gender and “sex” are much more complicated.

Take the developing story of Caster Semenya, who won a gold medal at the world championships in Berlin in August. There are unofficial reports in the media that she was examined and found to have testes instead of ovaries — and large levels of testosterone. This is more common than many of us would like to think. Her story brings the issues faced by the millions of intersex individuals in the world to mainstream America. Becoming informed of the factors involved in this case can help us all grow in tolerance around sexuality issues.

Medical experts estimate that at least 1 in 2,000 babies are born with some sort of intersex condition, of which there are more than 30. These can vary from chromosomal abnormalities, to reproductive or sexual anatomy that doesn’t fit typical medical, biological and cultural definitions of male or female.

In order to understand this complicated subject, we need to understand the difference between “sex” and gender. Male or female or intersex refers to a person’s biology — which anatomical, hormonal, reproductive and chromosomal parts with which the person is born. Sometimes, people are clearly biologically male or female. Sometimes, they are not.

Gender is something that is assigned to an individual. Are you a boy or a girl? A man or a woman? A person’s gender is more of an internal and cultural experience than their sex. Intersex conditions usually have to do with some sort of atypical development of sexual or reproductive body parts, which are usually (but not always) externally noticeable in some way.

Intersex is different from transgender. Intersex is a term that refers to the biological components of a person’s sexual organs. Transgender refers to gender identity — when a person internally feels they were given the wrong assignment at birth. For instance, if a person being raised as a girl believes and feels he is really a boy, then the internal gender experience is not congruent with the biology.

“Yes, but what do we do about it?” you may ask. It is possible to give a gender assignment at birth without doing medically unnecessary surgery. While some conditions require corrective surgery for health reasons, many do not. Doctors who are well educated in intersex matters can run proper tests and consult with parents about which gender their child is likely to identify with in the long run after puberty. This allows the person who is living in the body with the intersex condition to make a more informed choice about whether to have surgery to physically align with a certain gender. Contrary to popular belief, assigning a gender without surgical intervention has actually been shown to have less psychologically damaging effects than surgically “correcting” genitalia — and discovering later that was the incorrect choice.

Sometimes, especially if the medical personnel in charge are undereducated in these matters, the gender identity assigned at birth collides with the alternate gender hormones when they kick in at puberty, creating a gender identity crisis of sorts.

Whatever the case turns out to be regarding Ms. Semenya, I urge the sports world and world in general to withhold judgments, become educated and act from tolerance, compassion and with accurate information — rather than from fear of the unknown, old myths and antiquated terms.

Learn more

• Books: “Middlesex,” a Pulitzer Prize winning novel by Jeffery Eugenides; “Hermaphrodites and the Medical Invention of Sex,” by Alice Dreger.

• Articles: “Where’s the Rulebook for Sex Verification?” By Alice Dreger; and

“Olympic Problems with Sex Testing” by Alice Dreger

• Support groups: Intersex Society of North America