If I'm On Birth Control & Taking Antibiotics, Can I Get Pregnant?
Hey everybody! Today we are going to talk about antibiotics and birth control. So this is a really common question that we get, “Will taking antibiotics decrease the effectiveness of my birth control?” This is a loaded question. It’s an important question but there’s a lot of contributing factors so I’m going to do my best to clear the air for you today.
So tell me Leah, does my antibiotic make my birth control less effective?
The only antibiotic well studied that has proof and evidence based research showing that it does in fact decrease the effectiveness of your birth control is Rifampin. Now, this is used for tuberculosis so it’s not very common. But other antibiotics like penicillin, amoxicillin, azithromycin - the research on those has shown that it could possibly decrease the effectiveness of your birth control. For these common antibiotics, the research is really limited on their true effect of decreasing the effectiveness of your estrogen containing birth control and increasing your risk of pregnancy. The study sample sizes have been really small and so it's hard to generalize this to the entire population saying weather it does or does not affect your birth control.
As a general rule of thumb, if you’re on antibiotics and you take an estrogen containing birth control, use a backup method or a barrier method while you’re taking your antibiotics and for 1 week after.
To clarify, can I get pregnant?
Additionally, oral contraceptives have a failure rate of about 3% so with research it’s really hard to know if it’s user error or if it's actually the antibiotics causing these unwanted pregnancies. Like I said, as a general rule of thumb, use a backup method like condoms, while you’re on antibiotics, for one week after, and always take your antibiotics and birth control as prescribed by your doctor or provider.