Study	Reason for exclusion
Calderon‐Jaimes 1989	This was a prospective study where 986 pregnant women with asymptomatic bacteriuria were "divided in 2 groups", a treatment group that received nitrofurantoin 100 mg daily for 10 days and a control group. There is no further description of how the women were allocated to treatment or no treatment. The authors could not be contacted to provide clarification of the method of allocation and whether the women had been allocated to treatment group by a random or quasi‐random method.
LeBlanc 1964	In this study, all pregnant women with bacteriuria (N = 129), including those with urinary symptoms at the time of presentation, were randomised to 1 of 4 groups: no drug or 1 of 3 different antibiotic regimens that was continued until term at a prophylactic dose, once the culture had become negative. A group of patients with a history of urinary tract infection but negative cultures were also placed on randomised drug therapy. Results for the outcomes of pyelonephritis and prematurity for the group of women with asymptomatic bacteriuric (as compared to symptomatic infection or history of infection) were not provided separately. For the outcome of pyelonephritis, in the no treatment group, the outcome for women who were not treated and women who discontinued treatment were combined.
Mohammad 2002	This was an observational study. 1661 pregnant women were screened for bacteriuria by urine culture, for an overall prevalence of significant growth of 1.9%. There was no treatment intervention reported.
NCT03274960	The intervention in this study of pregnant women is screening for asymptomatic bacteriuria versus no screening, rather than randomising the women to treatment or no treatment for asymptomatic bacteriuria. In this study, set in a low‐resource setting in Zimbabwe, pregnant women presenting before 22 weeks' gestation will be randomised either to the control group and receive usual current antenatal services, which do not include any screening for asymptomatic bacteriuria, or to the intervention group. The intervention group will be screened for asymptomatic bacteriuria each trimester, using the Griess test (for the detection of nitrites in the urine), confirmed with culture, and symptomatic women will be treated. The number of preterm births between the 2 groups will be compared.
Rafalskiy 2013	In this study, pregnant women with asymptomatic bacteriuria (N = 112) were randomised to treatment with cefixime or amoxicillin/clavulanate. There was no "no treatment" group.
Sanderson 1984	In this study, 44 pregnant women with bacteriuria were treated with pivmecillinam, subsequently, 30 out of 33 women in whom treatment was successful were randomised to low dose pivmecillinam for 3 months, or no treatment. The group randomised to treatment, or no treatment did not represent the whole population of pregnant women with asymptomatic bacteriuria, but a subset of women in whom treatment had been successful.