They are taken during the fourth week, including during menstruation. Combination pills also come in 21-day packs. The pills are taken for three weeks. No pills are taken during the fourth week, when menstruation usually occurs. A new pack of pills is started seven days after the last pack is completed.
Menstruation usually occurs during the fourth week, no matter which series is used.
Be sure to follow the instructions on the package. You will also be advised whether you should start on a Sunday or on the first day of your period. Taking the Pill at the same time each day makes it more effective. It also helps you remember to stay on schedule. Pick a time of day that will be easy to remember.