This may be a little tmi but have any of you had problems with darkeninf skin?

I have pcos. One of the things common with pcos is acanthosis nigricans. Basically darkening of the skin. It's not harmful, but kind of embarrassing at times. Long before I got pregnant I delt with it in my underarms. Now I still have it on my underarms, a little on the back of my neck, but it's reallllly bad in my downstairs, where my legs meet my lady bits. My husband asked me about it the last time we were intimate and I knew it was there but I didn't know how bad it had gotten, it's really really dark.

I used to use Amlactin lotion on my underarms. Is that safe to use down there (obviously not directly on the lady bits), or while pregnant at all? I plan on talking to my OB about it at my appointment on Tuesday.