Objective: To evaluate the course of complicated supravesical obstruction in pregnant women, depending on the side of kidney damage. Material and methods: A retrospective study performed, on base of the State Institution “Republican specialized scientific-practical medical center of urology”. According to the inclusion and exclusion criteria, this study examined the case histories of 259 pregnant women, aged 16 to 42 (23.9 ± 0.12) years. Results: Evaluation of the duration of the disease showed that in patients with a single kidney it was statistically significantly (p <0.05) longer - 5.5 ± 2.7 days than in patients with unilateral kidney damage: with right-sided 0.7 ± 0.07 days t = 7.97, CI - 3.61-5.99), with left-sided (2.8 ± 1.4) with bilateral kidney damage 1.1 ± 0.33 days (t = 3.28, CI- 1,69-6,99). Conclusion: Pregnant women with bilateral complicated supravesical obstruction require a more thorough, in-depth examination and attention, early hospitalization for correction of hidden UTI in order to prevent serious complications in the form of acute pyelonephritis, urosepsis and surgical intervention (nephrostomy drainage installation, ureteral stenting, nephrectomy).