Sexually transmitted infections due not decrease the effectiveness of the birth control pill. It is possible to become pregnant while you have a sexually transmitted infection. However, if you were given antibiotics to treat the infection…..some antibiotics do interfere with birth control pills. We recommend that all pill users use a back up method the week they’re on the antibiotic and for the week after the antibiotic in order to prevent pregnancy.
Another cause of pill failure is not taking pills consistently. For some women, even missing 1 or 2 pills can lower the therapeutic level in the body enough to allow a break thru ovualtion.
22. January 2012
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