Can vaginal pH predict menopause?

OBJECTIVE To review the role of vaginal pH in the diagnosis of menopause. METHODS This descriptive cross-sectional study was performed in the Department of Obstetrics and Gynecology, Amir University Hospital, Semnan, Iran from March 2008 to March 2009 on 200 women (100 non-menopausal and 100 post-menopausal) from 45-65 years old. The pH paper was placed directly in contact in the lower third side wall of the vagina, and the pH was measured. Simultaneous sampling and culture of the vaginal discharge and blood samples for follicle stimulating hormone (FSH) was performed in the same day. Cases of bacterial vaginosis, trichomonas or other vaginitis were treated, and again 2 weeks later, the vaginal pH was measured. The gold standard for the diagnosis of menopause was FSH > or =35IU, hypoestrogenemia symptoms, and amenorrhea for one year. Receiver operating characteristic curve was used to determine the best cut-off point. The sensitivity, specificity, positive and negative predictive values were evaluated. RESULTS The mean +/- standard deviation age in the post-menopausal women was 58 +/- 3.8, and in non-menopausal women was 47.6 +/- 2. The vaginal pH in the diagnosis of menopause has a sensitivity of 92.7%, specificity - 83.5%, positivity - 84.9%, and negative - 92% predictive values (cut-off point > or =6). CONCLUSION Our study suggests that the pH of the vagina can be a good alternative to test for the diagnosis of menopause.