Morning Report

Which Antibiotics Should Be Avoided in Early Pregnancy?

Arefa Cassoobhoy, MD, MPH


May 05, 2017

Hello. I'm Dr Arefa Cassoobhoy, a practicing internist and a medical editor for Medscape and WebMD. Welcome to Morning Report, our 1-minute news story for primary care.

Antibiotics and Risk for Spontaneous Abortion

In a study of 182,000 pregnant women, the use of certain antibiotics during early pregnancy was linked with a higher rate of miscarriage before 20 weeks. These antibiotics included quinolones, tetracyclines, sulfonamides, metronidazole, and macrolides (except erythromycin).

Several of these, like azithromycin and ciprofloxacin, are commonly prescribed in the outpatient setting.

Antibiotics not associated with spontaneous abortion were penicillins and cephalosporins. Of note, nitrofurantoin also was not on the list. So it's a good option for urinary tract infections, one of the most common infections in pregnancy.

Now, the authors state that the severity of infection could be a confounding variable, but the message is still clear: While the overall danger is low, certain antibiotics are a safer choice for women of childbearing age.

For Medscape and WebMD, I'm Dr Arefa Cassoobhoy.

Follow Dr Cassoobhoy on Twitter at @ArefaMD


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