Pregnancy Risk After Antibiotics and Birth Control Pill

Question
hi- my girlfriendand i  had unprotected sex the day before her wisdom teeth were pulled. She is taking birth control but the following morning she took antibiotics as a pre-optic thing for the surgery. The antibiotic was lsited as 4 pills at once. These are the only antibiotics she took. We have not had sex since the surgery (four days or so) and i wanted to know if there is any risk of pregnancy because of this situation?

Answer
Theoretically antibiotics can reduce the effectiveness of the pill a little bit.  It's probably negligible most of the time.  In any case, she's fully protected by the time she's been off the antibiotics for a week.  In the meantime, using condoms might be advisable, although I'm not sure it's necessary.