I experienced a lot of pain while I was on YAZ . I was taking it as a treatment for PCOS. I took it for 3 weeks. I was instructed be my GYN to take it on the first day of my period. The first week, I had no complaints. The second week, instead of it ending - my period became a lot heavier. I started experiencing constant headaches, and sever bloating. My wedding band is usually loose around my finger. One morning I woke up and my finger was red and I could not get it off my finger. The third week, I started experiencing a lot of pain. The pain first started in my lower back, it felt a lot like back cramps. Then it started to intensify. By this time I also had cramps in my abdomen and groin area, and my ovaries felt like they were going to burst. The pain I was in , was equivalent to being in labor. I was rushed to the ER where they gave me morphine. I was in so much pain that the first two batches of morphine did not work. On top of all that, I was so sick. I was not able to hold anything down the whole last two weeks prior to there ER visit. I had no idea that YAZ was causing the pain, until the ER Dr. explained that I was not reacting well with the Yaz , and that I should stop taking it immediately. Oh and let me mention - I experienced sever mood swings, sometimes accompanied with rage like feelings. I went back to my GYN and she put me on Femcon Fe. I will never recommend the birth control YAZ to anybody. It is a horrible birth control pill in my opinion. It did not help me in any way it just made it worse. I give YAZ a big fat zero.