I have dark zones in my neck, inside elbows, abbots and bikini areamy gynecologist told me that my skin is too sensitive to hormones any treatment?

Acanthosis nigricans: Sounds like this which is not dangerous: http://kidshealth.org/parent/infections/skin/acanthosis.html. It happens in all types of people but there are certain groups that get it more. There is some relationship to hormones but not as much as you would think. No real treatment unless you have a medical condition that can be controlled that causes it.