Ninety-seven pregnant women with different stages and duration of chronic kidney disease (CKD) were examined. All the pregnant women were screened for bacteriuria in an outpatient setting. Fifty-five pregnant women were found to have a bacteriuria titer of 103 to 105 CFU/ml; 44 women exhibited no growth of microorganisms. All the pregnant women with CKD were established to be threatened by the joining/aggravation of frequently asymptomatic urinary tract infection (UTI) detectable in every three (38.2%) patients. Any degree of bacteriuria is important for patients with CKD and requires antibiotic therapy. An exacerbation of UTI during pregnancy is most commonly identified in patients with secondary chronic pyelonephritis, in whom the detection rate of bacteriuria is 70.2% and almost twice that in chronic glomerulonephritis (45%). Gram-negative microorganisms with the E. coli holding the lead in their structure are most frequently seen in the urine bacteriograms of pregnant women with UTI. The joining/aggravation of UTI in pregnant women with CKD affect the severity of perinatal outcomes: premature birth rates and intrauterine infection manifestations, determining the complicated course of early neonatal adaptation.