When I was diagnosed with PCOS (about 10 years ago), I had blood tests, an ultrasound and also saw a specialist and discussed the various symptoms. While the ultrasound didn't show much (though an internal may have) the blood tests and symptoms were enough for a diagnosis.

It took DF and I about 10 months of TTC before we got our BFP. I do believe there were other factors involved in it taking as long as it did, things were very stressful as I was working interstate, my Mum was very sick and I missed DF more than words can describe, but PCOS certainly didn't help. We saw a FS just to get everything checked and make sure PCOS was the only issue. DF's sperm analysis came back really good, everything else with both of us looked ok (though we were both encouraged to lose some weight) and the only realy issue was the fact that I wasn't ovulating. Due to my BMI they wouldn't put me on clomid so we stopped activly TTC and decided to focus on getting my weight down so we could go down that avenue this year, then within a month of us getting engaged and me shifting my focus from 'baby' to 'wedding' we were expecting. It was so annoying having everyone telling me to 'just relax' but I do think it helped big time. Not just relaxing about falling pregnant, but most of the stress in general had been removed