I am on the pill but got put on an one day antibiotic pill, Diflucan, for a yeast infection. A day after taking the pill, I had unprotected sex. Realizing that the antibiotic may cause the birth control to not work properly, I took plan B roughly 70 hours later. However, I started my sugar pills the day before I took plan b. I usually get my period 3 to 4 days into my sugar pills. I have yet to get my period but I have heard hormones in plan b can cause it to be late.  Is my period delayed just until my next cycle of sugar pills since I had to start a new pack or could I be pregnant?
Hi, I have read your question and would be pleased to answer. You do not need to take additional contraception to prevent the pregnancy as antibiotic do not interfere with oral contraception pills absorption However antibiotic rifampicin used to treat tuberculosis, and antibiotic causing diarrhea and vomiting as a side effect might affect absorption of contraception. If did do not have symptoms of diarrhea and vomiting while taking contraception then you should not be worried about pregnancy. Yes additional contraception can cause periods to be delayed as it causes hormonal imbalance, you might get your period as you finish up sugar pills. If you do not get your period after completing sugar pills take pregnancy test at home to exclude pregnancy to clear out your doubt or contact your health care provider. Hope this answer is helpfulThanks Chat Doctor.