Some antibiotics will decrease the effectiveness of your birth control pills. Recommendations are to use a back up birth control method for the time you’re on the antibiotics and for at least 7 days after completion of the antibiotics. Therefore, the effectiveness of your pills may not have been 100%. Anytime you have unprotected intercourse, there is the risk of pregnancy.
You probably do not need to take Plan B again, especially if you have continued to take your birth control pills on a daily basis. During this next month, you may experience some irregular bleeding or spotting. Your period may be a little earlier or later than usual, even though you’re taking the pills.
If your period is more than 1 week late, perform a pregnancy test.
8. February 2012
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