The aim of the study was to investigate if bacterial vaginosis (BV) is associated with use of specific contraceptives. Women at family planning and youth clinics (n = 956), among whom 131 had BV, were subjects for structured in-depth interviews including current and previous contraceptive use. Variables measuring sexual risk-taking were ascertained. Current users of contraceptives were compared with non-users. Both oral contraceptive (OC) and condom use showed a significant protective effect against BV, adjusted for possible confounders (odds ratios were 0.4 and 0.3, respectively). Intrauterine device use (IUD) showed no association with BV. Women with BV had less often used any contraceptives, including condom, at their sexual debut than the women in the comparison group. In this study, OC and condom use seemed to exert a protective effect against BV, whereas no effect for IUD use was found.
PIP: To determine whether bacterial vaginosis (BV) is associated with use of specific contraceptive methods, 956 women from family planning and youth clinics at 3 Swedish hospitals were enrolled in a cohort study. 131 women had at least 3 of the 4 clinical signs of BV: a homogenous gray vaginal discharge, a vaginal pH of 4.7, a positive amine test, and the presence of "clue" cells. Age at first intercourse was 16 years among those with and without BV; however, 8.4% of women with BV, compared with only 1.7% of controls, had had more than 1 sex partner in the last 6 months. Other factors associated with BV were more than 10 lifetime sex partners, non-use of contraception at first intercourse, a history of sexual abuse, an induced abortion, smoking, and alcohol consumption. After adjustment for sexual risk-taking, there was a significant negative association between BV and oral contraceptive (OC) use (odds ratio [OR], 0.4; 95% confidence interval [CI], 0.2-0.8). There was also a significant negative association with condom use (OR, 0.3; 95% CI, 0.1-0.9). There was no association between BV and IUD use, before or after adjustment for confounding factors. Insufficient numbers of diaphragm or spermicide users were available for analysis. The finding of an apparently protective effect against BV of OCs and condoms lacks a biological explanation at present, although it is speculated that OC use increases the glycogen content of vaginal epithelial cells, in turn inhibiting the in vitro growth of certain bacteria.