I have been on Yasmin for nearly a year. I have noticed some changes. The side effects are pretty mild for me and I don't think it has done more harm than good. However, I have noticed in myself
-Breast Tenderness/Swelling
-Weight Gain (we're talking like 20 lbs..)
-Blurred Vision (suddenly needed glasses?)
-Constant achy feeling
Other than that, I can't say much else other than it's helped me from getting pregnant. There were some other positive effects such as going from an A cup to a C cup over three months. :P
Good luck, ladies!