I have been on Lo Ogestrel for over 13 years. I usually take active pills for four months before taking the sugar pills for a week. This is both to control my periods, which have thankfully been short and light since I started the Lo Ogestrel, and to help manage severe migraines. Six weeks ago my pharmacy switched me to the other Lo/Overal generic Cryselle. I was surprised as heck to find that not only did I get my period today (I had the last one just 10 weeks ago, so this is nowhere near on schedule), but also that I am bleeding heavily and have horrible cramps, something I have never experienced in my life (and I m almost 40). The last time I had cramp like pain like this I had reoccurring ovarian cysts, which is what prompted my dr to put me on birth control in the first place. My question is could the simple change in generics cause this, even though they are essentially the exact same drug?