Oral contraceptives are powerful, but they’re not perfect. Often the problem is user error: Many of us have taken our Pill hours or even days late, which can decrease effectiveness. Plus, in rare cases, other medications or supplements, like St. John’s Wort, can interfere with the Pill’s function. If you have trouble remembering to take the Pill on time, it might be worth looking into other (non-daily) birth control options.

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