The placebo pills have no hormones in them. But, you are still protected from pregnancy during the 7 placebo pills as long as you’ve taken the first 21 pills correctly (One tablet by mouth once daily at the same time for 21 days in a row). This is because the active pills work in 3 ways – by preventing ovulation, thinning the uterine lining, and thickening the cervical mucus. These mechanisms are effective and long-lasting enough to keep you protected even through the inactive pill week as long as you’ve taken your pills correctly for the rest of the pack. Your period should start sometime during the placebo pills, and you should start your next pack of birth control the day after you take your last placebo pill, even if you are still having some period bleeding. Starting your next pack when it is due, regardless of period bleeding, will maintain your pregnancy protection. This removes the necessity of backup contraception during the first 7 days of each new pack. However, we always recommend the use of condoms for STI prevention and additional contraceptive benefits.
For more answers to your healthcare questions, visit our Knowledge Center.