Atlanta—Five years after recommendations to avoid certain antibiotics in pregnant women because of the possible risk of birth defects were issues, those medications are still being commonly used to treat urinary tract infections (UTIs) in that cohort, according to a report from the CDC.

The article in the Morbidity and Mortality Weekly Report points out that UTIs occur in about 8% of pregnant women and, if left untreated, can have serious effects, including pyelonephritis, preterm labor, low birth weight, and sepsis.

On the other hand, a 2011 committee opinion from the American College of Obstetricians and Gynecologists (ACOG) recommended that sulfonamides and nitrofurantoin be prescribed in the first trimester of pregnancy only when other antimicrobial therapies are deemed clinically inappropriate. The concern was a potential risk for birth defects, including anencephaly, heart defects, and orofacial clefts, associated with use of sulfonamides and nitrofurantoin during pregnancy.

For the recent study, the CDC analyzed the Truven Health MarketScan Commercial Database to see which antibiotic prescriptions were filled by pregnant women with UTIs. Results indicate that among 482,917 pregnancies in 2014, 7.2% of women had an outpatient UTI diagnosis during the 90 days before the date of last menstrual period (LMP) or during pregnancy. The most frequently prescribed antibiotics during the first trimester in pregnant women with UTIs were found to be nitrofurantoin, ciprofloxacin, cephalexin, and trimethoprim-sulfamethoxazole. 

“Given the potential risks associated with use of some of these antibiotics in early pregnancy and the potential for unrecognized pregnancy, women’s health care providers should be familiar with the ACOG recommendations and consider the possibility of early pregnancy when treating women of reproductive age,” researchers write.

The analysis notes that 34.7% of pregnant women with UTIs in 2014 filled a prescription for nitrofurantoin and 7.6% filled a prescription for trimethoprim-sulfamethoxazole during their first trimester of pregnancy.

“CDC’s analysis of a large insurance claims database demonstrated that, in 2014, nitrofurantoin and trimethoprim-sulfamethoxazole were common treatments for women with UTIs during their first trimester of pregnancy,” study authors conclude. “Improving antibiotic selection is an important aspect of antibiotic stewardship and these antibiotics have potential risks associated with early pregnancy use, particularly during organogenesis. Given the recommendations to avoid these medications in early pregnancy if possible and the fact that nearly 50% of pregnancies in the United States are unintended, it is important that healthcare providers of various specialties be aware of these recommendations and that they might be ‘treating for two’ when prescribing antibiotic treatments for UTIs to pregnant women and women who might become pregnant in the near future.”
« Click here to return to Weekly News Update.