He told me he is intersex

[Torn1990]

  My boyfriend recently told me that he is Intersex. I am not entirely sure what being intersex means,  because it seems it could mean different things for different intersex people. He doesn't know much about it himself...And he gave an appropriate response as to why. But I was curious if anyone here could inform me on what it really means to be intersex but show little to zero physical traits of possible visual evidence. Could being intersex ever mean your voice is more feminized then other males? He does seem to have a voice with a very mixed range, but mostly he sounds feminin. What are the chromosone possibilities for someone who is intersex and what could that do to the person who is intersex?
He seems more self conscious about being intersex even though it doesn't seem like he  has any reason too.
I am doing no research on intersex topics before this one.  Nor have I really breezed through the threads. 
He told me that during pregnancy he was identified as female until (i assume late pregnancy or..) birth. He also mentioned something about his chromosones. It all just sounds foggy to me... I will appreciate any serious responses.

PS: I accept my boyfriend as intersex, it doesn't change how I feel about him. But I do want to understand his feelings more and what it means to be intersex..

[kyril]

There are a number of different intersex conditions with different physical effects. Here's a short list:
http://www.isna.org/faq/conditions
Basically, what it means is that he has, or had at some point, primary sexual characteristics that are/were nonstandard for either males or females. He may or may not have unusual chromosomes; he may or may not have an unusual hormone balance; he may or may not have had surgery or hormone treatments to bring his body more in line with the standard male or female model; he may or may not be fertile, and his reproductive system (if intact) may be primarily male or primarily female or have elements of both. It's really impossible to generalize about intersex conditions because there are so many of them with such widely varying effects.

[insideontheoutside]

There are a number of different intersex conditions with different physical effects. Here's a short list:
http://www.isna.org/faq/conditions
Basically, what it means is that he has, or had at some point, primary sexual characteristics that are/were nonstandard for either males or females. He may or may not have unusual chromosomes; he may or may not have an unusual hormone balance; he may or may not have had surgery or hormone treatments to bring his body more in line with the standard male or female model; he may or may not be fertile, and his reproductive system (if intact) may be primarily male or primarily female or have elements of both. It's really impossible to generalize about intersex conditions because there are so many of them with such widely varying effects.

^Yes. This

There are more than what's on that list however too, but generally something physically has to different from the "standard" male or female body.