Seasonale is a highly effective form of oral birth control pill. It has estrogen and progesterone in each active pill, and there's an interval where you don't take any hormones, and in that interval, you get your menses or your period. The difference between Seasonale and the conventional birth control pills you're familiar with is that the Seasonale has more active pills and less placebo pills. In other words, Seasonale has 84 active pills in the pack, as opposed to your regular birth control pills, which may have only 21 or 24 active pills.
The big difference between the Seasonale and your monthly birth control pills is that you get your periods less often with the Seasonale. And that means that if you're a patient that gets headaches with your periods, if you get very painful periods, if you're a patient that doesn't want to get their periods in general, or if you're a patient that has heavy periods, you may benefit from using this form of birth control.
Because of the way that the formula is set up, you get your periods about four times a year. The only drawback, in addition to the same birth control side effects as the conventional pill, is that you can get breakthrough bleeding for a longer period of time. This does not decrease the effectiveness of this form of birth control. It's more of a nuisance. If you can ride that nuisance out for a couple of weeks and start the new pack of pills, it'll probably get better with the second pack of the Seasonale.
Again, the Seasonale is a highly effective form of birth control. It has estrogen and progesterone. The big difference is that you get your periods less often.