Effects of contraceptive method on the vaginal microbial flora: A prospective evaluation

A prospective evaluation of 331 university women who were initiating use of oral contraceptive pills (OCPs), a cervical cap, diaphragm-spermicide, or other spermicidal methods was done to assess the effects of commonly used c ontraceptive methods on the vaginal flora. Vaginal introital cultures were performed at baseline and then weekly for 1 month. The prevalence of Escher ichia coli vaginal colonization and of abnormal vaginal Gram stain scores ( Nugent criteria) increased significantly among women using a cervical cap o r diaphragm-spermicide but not among women using OCPs, Women with E. coli c olonization were significantly more likely to have an abnormal Nugent score and an absence of lactobacilli, In a multivariate model, use of spermicida l contraception in the preceding week was associated with an abnormal Nugen t score and with colonization with E. coli, Enterococcus species, and anaer obic gram-negative rods. Thus, spermicidal methods of contraception are ass ociated with alterations of the vaginal microflora that consequently may pr edispose women to genitourinary infections.