Seasonale, the first continuous-dosing contraceptive, was approved in 2003. It contains 81 days of active pills followed by 7 days of inactive pills. Women who take Seasonale have on average a period every 3 months. Seasonique, a follow-up to Seasonale, was approved in 2006. As with Seasonale, it produces about 4 periods a year. With Seasonique, a woman takes 84 days of levonorgestrol-estradiol pills followed by 7 days of pills that contain only low-dose estradiol.Standard oral contraceptives come in a 28-pill pack that contains 21 active pills and 7 inactive pills. Newer "continuous-dosing" (also called "continuous-use") oral contraceptives aim to reduce -- or even eliminate -- monthly periods and thereby prevent the pain and discomfort that often accompanies menstruation. Women who have medical conditions, (such as endometriosis), which cause heavy or painful menstrual periods may benefit from continuous-dosing oral contraceptives. These oral contraceptives contain a combination of estradiol and the progesterone levonorgestrel, but use extending dosing of active pills.
In 2007, the Food and Drug Administration (FDA) approved Lybrel, which supplies a daily low dose of levonorgestrol and estradiol with no inactive pills. Because Lybrel contains only active pills, which are taken 365 days a year, it completely eliminates monthly menstrual periods. In clinical trials, 59% of women who took Lybrel completely stopped menstrual periods by the end of the first year. Some women, however, experienced occasional unscheduled bleeding or spotting during the first 3 - 6 months.Progestin-only pills, which only contain progestins, are always sold in 28-day packs and all the pills are active. (An exception is Plan B, which is emergency contraception.) Progestin-only pills, which are also called "mini-pills," must be taken at precisely the same time each day to maintain top effectiveness. If a woman deviates from her pill schedule by even 3 hours, she should call her doctor about using back-up contraception for the next 2 days.
