Seasonique is a highly effective form of oral birth control pills. Seasonique has estrogen and progesterone in the active pills, and the formula is a little bit different than the Seasonale in that the hormone balance is different. The other difference between the Seasonale and the Seasonique is that in the week that you get your period, you're actually taking a little bit of estrogen each day. There's really no difference between the Seasonale and the Seasonique as far as the contraceptive effectiveness, but one may be a better form of birth control than the other.
Seasonique has 84 active pills, and 1 week of pills where you get your period. However, in that one week that you get your period, you actually take a little bit of estrogen with each pill. So it's very important when you use the Seasonique that you take every single pill in the pack, one day at a time, as you would normally take your birth control pills, but that one week that you get your period, you still need to take those pills, because that little bit of estrogen will help prevent you from getting pregnant and improve the side effect profile, which includes irregular breakthrough bleeding.