I had a quick search but I couldn't find the exact answer I'm looking for.
I'm on HBC (Millenette), yesterday was the first day of my 7 day break. My dentist prescribed me some antibiotics for 7 days which I also started yesterday. After a full days worth of medicine, I had unprotected sex. I looked up the antibiotics and they're said to interfere with HBC.. what are the chances of pregnancy?! Was one day of antibiotics enough to mess up my birth control?