Effect on vaginal pH of a polycarbophil vaginal gel compared with an acidic douche in women with suspected bacterial vaginosis: A randomized, controlled study

Background: Vaginal pH is a key factor in maintaining a healthy vaginal eco system. An increase in vaginal pH is commonly observed during bacterial vag inosis. Objective: This study was undertaken to compare the effects of polycarbophi l, a new bioadhesive polymer in gel form, with those of an acidic vaginal d ouche on restoration of physiologic vaginal pH in women with a vaginal pH g reater than or equal to4.5 and suspected bacterial vaginosis. We also asses sed the pH-lowering effect of a single application of polycarbophil compare d with that of a single application of acidic vaginal douche in an addition al group of women. Methods: In this controlled, randomized, investigator-blinded study, women aged between 18 and 60 years with a vaginal pH greater than or equal to4.5 and suspected bacterial vaginosis who were attending a gynecologic outpatie nt clinic for a routine visit were randomly allocated to receive polycarbop hil gel 2.5 g or an acidic vaginal douche twice a week for 6 weeks. We dete rmined vaginal pH by means of a pH meter and the presence of a fishy vagina l odor using a potassium hydroxide (whiff) test at baseline and after each treatment. Vaginal pH was measured in the lateral vaginal fornix at baselin e and at weeks 3 and 6 by an investigator who was blinded to treatment. In an additional group of women with a baseline vaginal pH>5.0, we assessed th e effect of treatment after a single application of polycarbophil or douche on vaginal pH at baseline and at 8, 32, 56, and 80 hours. Results: Of 45 women screened, 30 women, 2 of whom were pregnant, participa ted. All completed the study. An additional 8 postmenopausal women (mean ag e 56 +/- 5 years) received a single application of polycarbophil (n = 4) or vaginal douche (n = 4). Polycarbophil significantly (P < 0.001) reduced va ginal pH from 5.4 to 4.7 +/- 0.6 at week 3 and 4.6 +/- 0.7 at week 6 compar ed with baseline and with the vaginal douche group (5.4 +/- 0.5 at week 3 a nd 5.3 +/- 0.8 at week 6; not statistically significant). At the end of the study, vaginal pH was significantly (P < 0.04) lower in the polycarbophil group than in the vaginal douche group (4.6 +/- 0.7 vs 5.3 +/- 0.8, respect ively). Physical and microbiologic signs of bacterial vaginosis were also i mproved in the polycarbophil group. Both treatments mere well tolerated, wi th no adverse events as determined by the primary investigator. The pH-lowe ring effect of a single application of polycarbophil gel lasted significant ly (P < 0.01) longer than that of vaginal douche, decreasing from 5.5 at ba seline to 4.5 after 80 hours. Conclusions: Our findings show that; polycarbophil vaginal gel appears to r educe elevated vaginal pH to physiologic levels for 80 hours compared with acidic vaginal douche and to reduce vaginal pH in women with suspected bact erial vaginosis. Such reduction may help prevent the clinical complications associated with an altered vaginal pH. Randomized, controlled, clinical tr ials are needed to assess the role of polycarbophil vaginal gel in the long -term treatment of acute and recurrent bacterial vaginosis.