This study will evaluate the use of tinidazole to treat a woman's current BV infection and then will look at using tinidazole as a suppressive treatment (taking medication regularly to attempt to decrease the "bad" bacteria from growing back). The suppressive treatment phase will include using tinidazole twice a week compared to using placebo twice a week and then following women for recurrence of BV. The purpose of this study is to determine if tinidazole suppression will prevent BV from coming back within 3 months of treatment.