abnormal uterine bleeding
"After I had a reaction to Marvelon, my gyn gave me this saying that I would have a continuous supply of hormones never dropping.
No mood swings or panic attacks like on Marvelon but instead I got really bad vaginal pain. I had swollen up to the point that I couldn't put tampons in during that period. 
Needless to say if your allergic to latex and other plastics this might not be the method for you."