abnormal uterine bleeding
"I got on this birth control to regulate my period and get rid of acne. 
The only good thing about this was that my period started on the same day each month and it was shorter. The negative effects I had were bad acne, cramps worsened, period was really heavy, and heavy spotting the first 2 months. I figured I needed to wait at least 3 months for any good effects, but the negatives weighed out the positive and I'm now off of this medicine. I didn't gain any weight luckily. In fact, I lost some weight, but that could be a coincidence. The breakouts were the worst part about this birth control, though and that is why I'm not taking it anymore."