Anaerobic and other fastidious microorganisms in asymptomatic bacteriuria in pregnant women.

Urine from 44 pregnant women with known or suspected renal disease (group 1) and from 50 healthy pregnant women (group 2) with negative routine cultures of midstream urine was obtained by suprapubic aspiration. Aerobic and anaerobic cultures showed bacteriuria in 70% of the women in group 1 and in 26% of those in group 2. Gardnerella vaginalis was the most frequently isolated organism. Ureaplasma urealyticum was isolated from 14(48%) of 29 women in group 1 and from two (12.5%) of 16 women in group 2. Radiologic studies showed a high incidence of underlying renal disease in asymptomatic women with bacteriuria. Localization testing indicated kidney infection in six of 14 women in group 1 and in one of four women in group 2. These findings suggest that there is an increased susceptibility to colonization of the bladder with these microorganisms during pregnancy and that persistence of infection and renal involvement are associated with underlying renal disease.