I googled this and read about it, but I still don't understand what happens when you're on birth control and how your period can completely stop. So I read that progestin stops the uterin lining from developing. Is the uterin lining what allows you to ovulate? Or are they two separate processes that are affected by the progestin? How can the progestin stop the uterin lining from developing in some woman and still be just as effective in other women? And on another note, does a creamy, pasty textured discharge indicate that you are not ovulating?