Amniotic fluid U. urealyticum colonization: significance for maternal peripartal infections at term.

The aim of this study was to examine the relationship between maternal peripartal infectious morbidity and amniotic fluid colonization by U. urealyticum. Amniotic fluid specimens for bacterial and mycoplasmal cultures were obtained by aspiration at nonelective cesarean section from 98 pregnant women. Amniotic fluid cultures revealed micro-organisms in 70 (71%) parturients and U. urealyticum was the most frequently isolated species, detected in the specimens from 38 (39%) women. In the total study population, the prevalence of clinically defined infectious morbidity was 26%, including 8 (8%) patients with chorioamnionitis, 11 (11%) with endometritis, 5 (5%) with urinary tract infection, and 4 (4%) with wound infection. A significant association between the amniotic fluid U. urealyticum colonization and increased maternal peripartal infectious morbidity was observed (p < 0.0027; relative risk 4.1; 95% confidence limits 1.6 to 10.7). Amniotic fluids positive for U. urealyticum were significantly more often positive for other potentially pathogenic bacteria (p < 0.0024) and particularly for Bacteroides spp. (p < 0.0074). Our results support the existence of an association between amniotic fluid U. urealyticum invasion and maternal infectious morbidity. However, U. urealyticum was not usually isolated alone from amniotic fluids but combined with other pathogenic bacteria, the severity of infections were not enhanced when U. urealyticum was present and parturients with diagnosed infections managed well without specific antibiotic against U. urealyticum. Hence, it appears that the significance of U. urealyticum in maternal infections in this study population was mainly based on its interactions with other bacteria.