[Cervico-inguinal microbiology, vaginal pH, infections, and premature labor]

Preterm labor is the leading cause of perinatal morbidity and mortality. There is increasing evidence that inflammation of the upper genital tract, deriviated by lower reproductive tract infections (cervicitis or vaginitis), may play a major role in the pathogenesis of preterm labor, premature rupture of membranes and preterm birth. These complications are potentially preventable with prompt diagnosis and treatment in pregnancy. Alterations of the vaginal ecosystem with change in vaginal pH, are presupposition for infections and their consequences.

To investigate the relationship between cervico-vaginal infections and related events such as expression of bacterial enzymes and change in vaginal pH with preterm labor.

In our study we identified cervico-vaginal infections during gestation week 8-14 and 30-34, using three different diagnostic tools: 1) microbiological tests; 2) assessment of vaginal pH; 3) detection of bacterial enzymes. Then, we correlated these events to perinatal outcome. Among 200 pregnant women a pH greater than 4.6 was detected in 38% of all cases. Among microbiologically positive patients, vaginal fluid pH was positive, in particular, in 75% cases of Bacterial vaginosis.

pH assessment along with symptoms and signs could be used as initial screening test to alert physician to vaginitis. When vaginal fluid pH is used to screen for Bacterial vaginosis, it has a greater sensitivity than when used to screen for all causes of vaginitis.