Somewhat Damaged

I have health insurance now through my employer, and it's pretty good. I've seen mention of women being denied health insurance because of their PCOS diagnosis and was just wondering if anyone had information on why this happens (aside from the obvious of the health insurance companies sucking, etc.), and how to prevent it.

Does this mainly happen to people seeking to purchase their insurance privately, or has this happened to women who have benefits through their employers.

I also saw Kat mention in another thread that it's wise to prevent doctors from using diagnostic codes for PCOS unless absolutely necessary. Does anyone have any more information on this? I'm trying to think ahead....

Thanks.