Inability to enroll patients at anticipated rate.

This is a prospective randomized controlled day comparing the efficacy of three-day antimicrobial treatment of asymptomatic bacteriuria (ASB) in pregnancy to the standard seven-day treatment. Half the patients will receive 3-day treatment and the other half will receive 7 days of antibiotics.

The current standard of practice is to treat pregnant patients with ASB with a 7-day course of oral antimicrobial agents. If bacteriuria persists women are retreated with the same of different agent for a second course of 7 to 14 days and they may be subsequently placed on prophylaxis.

In nonpregnant women, an uncomplicated lower urinary tract infection may be treated with a short course regimen from 1 to 3 days. This approach has similar rates of persistent bacteriuria or symptoms following treatment when compared to women treated with a more conventional approach. If the infection recurs or persists, the patient may then be treated with the more traditional 7 to 14 day course. The advantages of single-dose regimens are cost and patient compliance, but a major disadvantage is the failure to eradicate uropathogens from the vaginal reservoir, which results in more frequent early recurrences.

The three-day regimen is advocated to maintain the advantages of lower costs and patient compliance but improving cure rates. Multiple studies have shown the advantage of even a short course of antibiotics as opposed to no treatment.

Inclusion Criteria:

• Pregnant women ≥ 18 years of age seeking prenatal care at the Academic Obstetrics and Gynecology Center at St. Joseph Mercy Hospital, Ann Arbor, Michigan
• Randomization will occur if the patient every has a urine culture demonstrating ≥10,000 cfu/ml of a pathogenic urinary tract organism

Exclusion Criteria:

• Symptomatic bacteriuria (cystitis or pyelonephritis) at the time of urine collection
• Previously treated bacteriuria in current pregnancy
• Past medical history of known congenital or acquired urinary tract anomaly or abnormality (i.e. pelvic kidney, single kidney, renal transplant)
• Any antibiotic use within the week prior to urine sampling
• Urine culture revealing growth of the following organisms: Lactobacillus, coagulase-negative staphylococcus