I took 1,000mg of azithromycin friday and had sex saturday. i am on the pill and we did not use a condom. should i be worried about pregnancy?

Well,...: Antibiotics ca decrease the efficacy of Birth control by less than 1%, so there is a small chance. Doubtful as the chances are small, but still you need to know the risk of pregnancy does go minimally up compared to NOT being on an antibiotic. I recommend condoms too supplement Birth control pills when taking antibiotics. Best wishes.

Yes, if ...: Yes, if you took your contraceptive pill within 20 minutes of your antibiotic pills, as the latter pill will be absorbed and the former pill will not be absorbed with a pregnancy risk. Antibiotics should not be taken at the same time as a contraceptive pill. If that is not the case, no worries.