What is the appropriate treatment for Urinary Tract Infection (UTI) during the first trimester of pregnancy?

From the Guidelines

Urinary tract infections (UTIs) during the first trimester of pregnancy should be treated promptly with nitrofurantoin (Macrobid) 100 mg twice daily for 5 days, as recommended by the European Association of Urology guidelines [ 1 ]. This treatment is preferred due to its effectiveness against common UTI pathogens and good safety profile during pregnancy. The following points support this recommendation:

• Nitrofurantoin is a first-line treatment option for uncomplicated cystitis in women, including those in the first trimester of pregnancy [ 1 ].
• The European Association of Urology guidelines suggest a 5-day course of nitrofurantoin for the treatment of uncomplicated cystitis [ 1 ].
• Other treatment options, such as trimethoprim-sulfamethoxazole, are not recommended during the first trimester of pregnancy due to potential fetal harm [ 1 ].
• Patients should complete the entire course of antibiotics, even if symptoms improve, and follow up with their healthcare provider after treatment [ 1, 1 ].
• Urine culture before treatment is recommended to ensure appropriate antibiotic selection [ 1, 1 ]. Key considerations for UTI treatment during the first trimester of pregnancy include:
• Prompt treatment to prevent complications like pyelonephritis, preterm labor, or low birth weight
• Selection of antibiotics with good safety profiles during pregnancy
• Completion of the entire course of antibiotics to ensure effective treatment
• Follow-up with a healthcare provider after treatment to monitor for potential complications or recurrence of UTI.

From the Research

UTI Treatment During First Trimester

• The treatment of urinary tract infections (UTIs) during the first trimester of pregnancy is crucial to prevent complications and ensure the health of the mother and the fetus 2.
• According to a study published in 1994, limited data are available regarding the appropriate antibiotic management of UTI in pregnancy, but single-dose cure rates with amoxicillin are approximately 80 percent, and trimethoprim/sulfamethoxazole provides cure rates of greater than 80 percent 2.
• The study recommends separating pregnant subjects with UTI into two groups: those with asymptomatic bacteriuria can be treated with a single dose of an antimicrobial to which the organism is susceptible, and those with symptomatic UTI can be treated with amoxicillin 500 mg tid for three days 2.
• Another study published in 2020 discusses the treatment of UTIs in general, including the use of nitrofurantoin, fosfomycin, and pivmecillinam as first-line empiric antibiotic therapy for acute uncomplicated bacterial cystitis in otherwise healthy adult nonpregnant females 3.
• However, it is essential to note that the treatment of UTIs during pregnancy may differ from that in nonpregnant women, and the choice of antibiotic should be based on the susceptibility of the organism and the safety of the antibiotic during pregnancy 2.
• A study published in 2022 evaluated the effectiveness of nationally recommended antibiotics for the treatment of UTI in U.S.-Mexico border emergency departments and found that oral antibiotics with comparatively lower resistance rates were amoxicillin/clavulanate, cefdinir, cefuroxime, and nitrofurantoin 4.
• Another study published in 2024 evaluated the use of oral amoxicillin/clavulanate for UTIs caused by ceftriaxone non-susceptible Enterobacterales and found that amoxicillin-clavulanate may be a useful alternative therapy for the treatment of ceftriaxone non-susceptible Enterobacterales UTIs 5.
• A study published in 2022 evaluated uropathogens, antibiotic susceptibility, and empiric treatment of UTIs in long-term care facilities and found that amoxicillin/clavulanate and nitrofurantoin are appropriate first-line options for empiric treatment of symptomatic cystitis 6.

Antibiotic Options

• Amoxicillin: single-dose cure rates of approximately 80 percent 2.
• Trimethoprim/sulfamethoxazole: cure rates of greater than 80 percent 2.
• Nitrofurantoin: first-line empiric antibiotic therapy for acute uncomplicated bacterial cystitis in otherwise healthy adult nonpregnant females 3.
• Fosfomycin: first-line empiric antibiotic therapy for acute uncomplicated bacterial cystitis in otherwise healthy adult nonpregnant females 3.
• Pivmecillinam: first-line empiric antibiotic therapy for acute uncomplicated bacterial cystitis in otherwise healthy adult nonpregnant females 3.
• Amoxicillin/clavulanate: useful alternative therapy for the treatment of ceftriaxone non-susceptible Enterobacterales UTIs 5.
• Cefdinir: oral antibiotic with comparatively lower resistance rates 4.
• Cefuroxime: oral antibiotic with comparatively lower resistance rates 4.