One of the few judicial decisions to deal explicitly with intersex conditions came in 1999 from the Constitutional Court of Colombia.

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Ultimately the sex chosen for an intersex baby is the one doctors and their family believe they will grow up to identify with best.

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Intersex conditions occur in one out of every 2, 000 births in the United States, according to the Rohnert Park, California-based Intersex Society of North America.

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Most groups campaigning for intersex people now advocate that doctors should not perform medically unnecessary genital surgeries on intersex babies to make them male or female.

CNN: Gender row athlete: What is intersexuality?

It could invalidate some unions involving an intersex partner, but also allow a genetic male and female to marry even if they look as if they belong to the same sex.

ECONOMIST: Sex is a complicated thing to define

According to a report released in May 2011 by the International Lesbian, Gay, Bisexual, Trans and Intersex Association, same-sex relations are still criminalized in 76 countries, and in five of those countries the death penalty can be applied.

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People who are intersex could also have the condition and not be aware of it, as was the case of Indian athlete Santhi Soundarajan, who failed a gender test at the 2006 Asian games and was stripped of her medal.

CNN: Gender row athlete: What is intersexuality?

According to a report released in May 2011 by the International Lesbian, Gay, Bisexual, Trans and Intersex Association, same-sex relations are still criminalized in 76 countries, and in five of those countries, the death penalty can be applied to those who violate the laws.

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