The impact of pig farming on the worldwide economy causes production to be directed at an industrial scale, requiring the control of diseases that affect economic performance. Urinary infection (UI), for example, has a high prevalence in current production systems, causing economic losses due to the predisposition to reproductive failures, leading to an increase in disposal of sows and replacement rates. In this context, the objective of this work was to evaluate the prevalence of urinary tract infection (UTI) and possible changes in the urine sediment examination of pregnant sows to survey changes compatible with inflammation of the lower urinary tract. The samples were collected, randomly, from 43 sows of commercial genetic lineage, in different stages of gestation, and that belonged to a pig farm located in Guapimirim-RJ. The pig farm’s herd consisted of 200 sows, 90 of which were in the gestation phase. The samples were collected by spontaneous urination, using the first morning urine, before feeding, which happened around 7 am. The presence of UTI was identified in 12 of the 43 sows analyzed, with 21.5% of the herd being evaluated. A prevalence of 27.9% was observed with animals showing compatible UTI changes. This data was considered severe. The urine sediment examination is the best way to diagnose UTI with sedimentcopy being the most conclusive part. Despite this, it is necessary to relate the laboratory data with the zootechnical management used, as well as the environmental conditions.