I've been on the pill for a couple years, and after getting a pap smear I was given some medication for a UTI I never had symptoms of, but was told was found. The nurse who called me told me I couldn't drink while I was on the medication, but never said anything about interference with BC.

I started taking the medications last Thursday, and on Sunday had.. intercourse.. with someone I've been seeing here and there for a while.. we both got tested and trust each other, and since I'm on the pill we don't use protection.

Last night while checking how long the meds I'm on (until tomorrow) would keep me away from alcolhol (because I want to go out with friends this weekend) I stumbled upon the warning that the medication can make birth control ineffective.

I am aware that I have to wait a month to see whether that night will have consequences, but I was just wondering if there's anything I should be doing differently until that time just in case. I'm a university student, and I know that you can't drink and eat a bunch of things during pregnancy, but if I just go on (drinking and not watching what I'm eating), if I am pregnant will that be harmful to the fetus?

Antibiotics can diminish the effectiveness of birth control pills so it is often suggested to use a condom during the medication as an extra precaution. Odds are that the one time incident will not result in a pregnancy, but you may want to avoid alcohol and watch what you eat until you know for sure. It won't be a long time to have to abstain.

It would be wise to be on a multivitamin with 400 mcg (more is fine) of folic acid just because you are of childbearing age and pregnancy will still be a possibility even while on the pill. Having enough of this vitamin can help prevent certain birth defects that occur very early in a pregnancy. So even women who are not trying to get pregnant should be on it just in case an unexpected pregnancy occurs.