Sexuality talk with my new Gynecologist?

Azkadellia • Currently just trying to get my body to do what it`s supposed to. Lesbian.
*Let me just say, I would have posted this in the LGBTQ groups. However, they aren't really active and I need advice.*
Okay, so I'm 19 and a lesbian. I'll be 20 in December, and have a girlfriend of two years. Whom I plan on marrying, I'm being transferred (by my choice) to a new gynecologist and women's health office that offers artificial insemination assistance and specializes in PCOS (which I have) and Endometriosis (I suspect I have it too). My problem is, how do I approach the topic of my being a lesbian with my new doctor?
I haven't ever told any doctor that I'm a lesbian, mostly because I'm a virgin and and once you answer "no" to the "are you sexually active?" Question, the sex talk usually doesn't go any farther. But I figure, if I'm going to be sticking with this doctor and clinic (which, I really hope to.) I need to get around to having that talk with this new doctor, I just don't know how to bring it up. 
I feel like it's an important thing for a doctor to know, because obviously a lesbian couple won't be conceiving naturally and with my added fertility issues. We'd like to start TTC after we marry in the next year or two. So, how would you bring this up with the doctor?