Longer antibiotic regimen superior for prenatal bacteriuria

February 15, 2009

A 1-day regimen of nitrofurantoin is markedly less effective than a 7-day regimen to treat asymptomatic bacteriuria in pregnant women.

A 1-day regimen of the antibiotic nitrofurantoin is markedly less effective than a 7-day regimen to treat asymptomatic bacteriuria in pregnant women, according to research published in the February issue of Obstetrics & Gynecology.

Pisake Lumbiganon, MD, of Khon Kaen University in Thailand, and colleagues compared the 1-day versus 7-day antibiotic regimen in a multicenter, double-blind non-inferiority study that randomized 778 pregnant women with asymptomatic bacteriuria to receive either dosage schedule. Nearly half of infections were due to Escherichia coli. The primary study outcome was bacteriologic cure at day 14.

The rates of bacteriologic cure at day 14 were 75.7% and 86.2% for the 1-day and 7-day regimens, respectively, the investigators found. The researchers report that this 10.5% difference indicated that the 1-day regimen was significantly less effective compared with the 7-day regimen. In addition, preterm delivery and low birthweight were more frequent in patients receiving the 1-day regimen, leading to significant decreases in mean birthweight and mean gestational age at delivery, the report indicates.

Lumbiganon P, Villar J, Laopaiboon M, et al. One-day compared with 7-day nitrofurantoin for asymptomatic bacteriuria in pregnancy: A randomized controlled trial. Obstet Gynecol. 2009;113:(Pt. 1):339-345. doi: 10.1097/AOG.ob013e318195c2a2