Figure 1.

Hazard ratio of BV by contraceptive method, relative to women using no contraception or a nonhormonal contraceptive method other than Cu-IUD. Analyses were conducted including (1) all BV evaluations, (2) only regularly scheduled BV evaluations, (3) estimated hazard ratio for those without recent exposure to an alternative hormonal contraceptive, and (4) estimated hazard ratio for those without current or recent concomitant additional hormonal medication use to treat heavy and/or intermenstrual bleeding. The proportional hazards assumption was appropriate for all models. Abbreviations: BV, bacterial vaginosis; Cu-IUD, copper intrauterine device; DMPA-IM, intramuscular depot medroxyprogesterone acetate; NET-EN, norethisterone enanthate; OCP, oral contraceptive.