Intersex is a medical condition when a person is born with both genitals and I believe the idenity is unknown.

First, there would have to be all sorts of tests (medical, psychological, etc.) done to determine the person's gender. Surgery would be the last stop on the road to wholeness.

Being Intersexual (http://www.romanceopedia.com/A-BeingIntersexual.html)

If the process is anything like the one to become transexual, then there's at least a year of therapy required before the final surgery.

I do know one thing; they look at the funstionality of the organs when determining sex. If the penis is non-functional, or the vagina is more of a vestigial opening than a birth canal, then the choice becomes easier. It's VERY rare for both sets of organs to be fully functional.

Also, there's no chance of the genes being passed down to children. The same genes that cause harmaphidism (intersex) cause sterility.