Previous studies revealed that 22% to 40% of sows in confinement operations are affected with urinary tract infections (UTI), which contribute to sow mortality. This study was designed to determine if UTI are detrimental to sow performance and to identify the stage of the production cycle that sows are at greatest risk of acquiring UTI. The study was conducted on a commercial sow farm and urine samples were collected from sows in late gestation, shortly after farrowing, in late lactation, after weaning and during early gestation. Our results demonstrated that abnormal urine samples were more common in sows during lactation and postweaning than in gestating sows. Based on urine evaluations, it was evident that water intake was insufficient in late lactation. Some sows appeared to recover from the UTI with the sole intervention of increased access to water in the gestation/breeding facilities. The study farm provided free choice water to sows in breeding and gestation. We suspect that many sows have cystitis to varying degrees and remain “subclinical”. Unless the infection ascends to the kidney, the infection is not necessarily life-threatening and remains undetected. Surprisingly, the subclinical UTI, as detected with urinalysis methods, do not appear to interfere with sow reproductive performance. Urine abnormalities, indicative of UTI, are common in sows; however, it is evident that further refinements of urinalysis methods are required to adequately predict the outcome of UTI.