so beginning in January I noticed my skin on my upper thigh and at the base of my vulva and into my butt has gotten dark! when using a flashlight to look at it, it kind of has a yellow hue as well as a dark brown tone. my insulin last checked was only 3 points higher than normal and a normal a1c. my gyno thinks acinthosis nigrocins, my regular dr didn't know, and one dr said friction. only 2 instances I think of that i would have gotten chaffed and after that i started wearing chafe shorts... (I walk so much at work) but would it really have gotten this dark from one chafe episode?! years of my lower thighs rubbing has only made it barely darker than my regular skintone.... so i don't get it. I feel gross and unattractive. can I do anything to lighten it? what is it? the dark areas are dry and look thin and fragile looking now. help please!