I started taking YAZ about about 5 months. The biggest side effect I notice is SEVERE migraines 2 days before my period starts. I am a speech therapist and found it almost debilitating to try to work with my clients today because my head was pounding out of my head. I was also experiencing some blurry vision while driving (not good). On the bright side my adult acne has cleared up and periods have shortened by about 5 days. Regardless, I've decided that if something inflicts head pounding migraines then it is not worth it. I'm going to drop birth control for good as I haven't found any that I like at the age of 37.