Vaginal nitric oxide in pregnant women with bacterial vaginosis

Problem To evaluate vaginal nitric oxide (NO) production in response to alterations in the vaginal microbial flora. Method of study Cervicovaginal lavage samples from 206 women at 18-22 weeks of gestation were tested for NO, interleukin-1 beta (IL-1 beta), IL-1 receptor antagonist (IL-1ra), tumor necrosis factor-alpha and the inducible 70 kDa heat shock protein (hsp70). Bacterial vaginosis (BV) was diagnosed based on gram staining of vaginal smears. Results and conclusions Elevated NO (> 2.14 mmol/L) was associated with a diagnosis of BV (38% versus 11%, P < 0.008) as well as an increased median vaginal IL-1ra concentration (72.5 ng/ml versus 36.6 ng/ml, P = 0.041). Elevated vaginal NO was also associated with vaginal hsp70 and this relationship was independent of BV status or IL-1ra concentrations (P < 0.026). We conclude that vaginal hsp70 release in response to abnormal vaginal microflora may trigger NO production in an attempt to minimize the pathological consequences of this altered milieu.