According to the results of a recent study published in the Morbidity and Mortality Weekly Report, nitrofurantoin and trimethoprim-sulfamethoxazole were commonly prescribed to pregnant women with urinary tract infections (UTIs) in their first trimester of pregnancy, against the recommendation of 2011 guidelines from the Infectious Diseases Society of America and the American College of Obstetricians and Gynecologists.
To evaluate antibiotic use for UTIs during pregnancy, researchers evaluated 482,917 pregnancies that occurred in 2014 among women aged 15 to 44 years. Insurance claims during the 90 days before the date of the last menstrual period through the end of pregnancy were evaluated for outpatient UTI diagnoses, and pharmacy claims were evaluated for antibiotic medications dispensed up to 7 days after the UTI diagnosis.
In this study, a total of 34,864 (7.2%) pregnant women had a UTI diagnosis during pregnancy or during the 90 days before the last menstrual period. UTI diagnoses were more frequent in the first trimester of pregnancy compared with the third trimester (41.0% vs 11.8%).
Women with UTI diagnoses before pregnancy were more likely to fill an antibiotic prescription compared with those diagnosed during pregnancy (76.1% vs 68.9%). During the first trimester of pregnancy, the following antibiotics were the most commonly used: nitrofurantoin (34.7%), ciprofloxacin (10.5%), cephalexin (10.3%), and trimethoprim-sulfamethoxazole (7.6%).
Fluoroquinolones and sulfonamides were more commonly administered to women diagnosed with UTIs before the last menstrual period, whereas nitrofurantoin, cephalosporins, and penicillins were more commonly administered to women diagnosed with UTIs during pregnancy.
The study authors concluded that “given the recommendations to avoid [nitrofurantoin and trimethoprim-sulfamethoxazole] in early pregnancy if possible and the fact that nearly 50% of pregnancies in the United States are unintended, it is important that health care 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.”
Ailes EC, Summers AD, Tran EL, et al. Antibiotics dispensed to privately insured pregnant women with urinary tract infections – United States, 2014. MMWR Morb Mortal Wkly Rep. 2018;67:18-22.