What Causes Acne Vulgaris?

Hi, my name is supriya and i am 25yrs old . My weight is 51kg and height 5'4. I am suffering from ance vulgaris from past 10 yrs. I have tried almost everything. Have taken multi medical treatments. Some has helped but only for short period of time but when the affect of medicine goes acne starts coming back again.In addition to it ,i had been taking Azithral tablets for 1 yr. It had helped to few extent but the time i discontinue it, it starts coming back again. As per doc advice i have undergone sonography test which has detected that my both ovaries are enlarged and multiple small follicles are noted in both(Rt ovary-3.5*1.3/Lft ovary-3.6*1.8). Please help me to get permanent rid of acne.