Relationship of bacterial vaginosis and mycoplasmas to the risk of spontaneous abortion

OBJECTIVE: This study was undertaken to investigate a possible link between first-trimester diagnosis of bacterial vaginosis and cessation of pregnancy at less than or equal to 20 weeks' gestation. STUDY DESIGN: Women (n = 228) who received routine prenatal care in Flanders, Belgium, during the first trimester (14 weeks' gestation) and had a living singleton fetus were examined for microbiologic flora of the vagina. Bacterial vaginosis was assessed either clinically (Amsel et at criteria), microscopically (clue cells), or by culture of bacterial vaginosis-associated bacteria. Data were analyzed univariately (relative risk) and multivariately. RESULTS: The presence of bacterial vaginosis at the first prenatal visit was strongly associated with subsequent early pregnancy loss (relative risk, 5.4; 95% confidence interval, 2.5-11). After multivariate analysis bacterial vaginosis, Mycoplasma hominis, and Ureaplasma urealyticum but not other microorganisms remained associated with an increased risk of miscarriage. CONCLUSION: Bacterial vaginosis and mycoplasmas may play causative roles in spontaneous abortion and early pregnancy loss.