i have had pcos for 6 1/2 yrs. they found mine by doing some blood work and an ultrasound but they also ask you a lot of questions about your body and eating habits if you think you have pcos i would reccomend that you go to your gyn.
they will run a series of blood tests, but i would first go to your gyn. and go from there. do you have abnormal periods? or anything like irregular bleeding, increased hair growth.. acne? if you feel you have any symptoms of it, then go and get it checked, and they will be able to determine if you do or not. If you do, then they will take a course of action that is best for you.