endometriosis
"My body does not react very well to hormones. I spent just over a week on this medication and experienced vomiting every single day. My physician mentioned that nausea was normal so I assumed this was typical, as my stomach is generally a little more sensitive than most, anyway. Besides, it wasn't too bad - just once in the morning. Once my body had woken up, I was just fine. 

However, the last few days I was on the medication, the adverse reactions increased. Vomitting increased to several times throughout the day, nausea increased from the first few hours of the day to the entire time I was awake, and had several fainting spells accompanied by severe twitching (luckily my doctor ruled out seizures). Scary!"