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If you have been taking the active pills regularly without missing a pill then you are quite protected for pregnancy as the sugar pills are just placebo and are reminder pills to keep your schedule going.They do not have any effect on the hormonal levels.But after 7 days start the active pills on the due date.If you miss these pills in a row then you need to start the cycle again and you would not be protected then.
While on sugar pills days you can have safe intercourse and Plan B is not required.
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