One day administration of nitrofurantoin versus a 7 day course in the treatment of asymptomatic bacteriuria in pregnant women

The aim of a multicenter, double-blind, randomized, placebo-controlled study in the Philippines, Argentina and Vietnam was to assess the effectiveness of a one-day course of nitrofurantoin compared to a standard course of 7 days in the treatment of asymptomatic bacteriuria in pregnant women. The study included pregnant women who sought medical help from March 2004 to March 2007. Patients were randomized to receive either one day or seven day treatment of nitrofurantoin, which was prescribed at a 100 mg dose twice a day.

The primary outcome measure was the incidence of bacteriological healing on day 14 from the start of treatment.

Of the 24,430 women who saw a doctor, 1,248 were diagnosed with asymptomatic bacteriuria, that is, the prevalence of this condition was 5.1%. Out of 1248 women eligible to participate in the study, 778 were included in the protocol and randomly assigned to receive either one-day (n = 386) or 7-day (n = 392) treatments.

The most common pathogen was Escherichia coli, which was isolated from approximately 50% of the study participants. The frequency of bacteriological cure on the 14th day since the start of treatment was 75.7% (one-day treatment) and 86.2% (7-day treatment). The differences in the frequency of eradication of pathogens from the urine were -10.5% (95% confidence interval -16.1% -4.9%). The mean birth weight and mean gestational age at delivery were significantly lower in the group of women who received nitrofurantoin for 1 day. Fewer adverse events were noted in the day treatment group, but these differences were not statistically significant.

Thus, one day treatment of asymptomatic bacteriuria with nitrofurantoin in pregnant patients was significantly less effective than 7 days of treatment. Researchers recommend that all pregnant women with this condition prescribe standard 7-day treatment with nitrofurantoin.