Yaz is a low dose birth control pill that is often prescribed for women with PCOS. However, as an expert in PCOS..I would not recommend this treatment. Any birth control pills tend to mask the PCOS symptoms without actually treating anything. The correct treatment for PCOS is low carb diet, exercise and using an insulin sensitizing drug such as metformin. Many doctors still believe in prescribing birth control pills but there is more and more research showing this is not good. If you research it online, you will find TONS of negative info about BCP and PCOS.
Here's a great general site about PCOS.
http://pcos.itgo.com/
Here's another great site about PCOS:
http://www.inciid.org/faq.php?cat=infert…
Provera is different than Depo-provera (which is the shot thing others mentioned). Provera is a form of progesterone given to women to bring on a mentrual cycle. It does not cause ovulation. You take provera for several days (usually 10-12 days) and then when you stop, you start your period a few days later.