The investigators propose to explore the hypothesis-supported by limited data-that a contraceptive vaginal ring (CVR) that is commonly used in the United States, the NuvaRing, will enhance women's genital and reproductive health. The investigators propose that this CVR will increase the bacteria that help the vaginal environment protect against infection by HIV and other STIs, and that in women who already have HIV, use of the CVR will lower the quantity of HIV that is shed in the female genital tract.

The investigators objective is to study effects of a contraceptive vaginal ring (CVR) containing estrogen and progesterone (NuvaRing) on vaginal bacteria, HIV shedding, and local immunity in women. The investigators will build on data that support a favorable effect of CVR on vaginal bacteria. Bacterial vaginosis (BV) is found in >50% of women in sub-Saharan Africa. BV significantly increases risk of HIV acquisition in, and HIV transmission to male partners from, HIV-infected women, genital HIV shedding, and viral set point in infected male partners. Pregnancy is also an independent risk for HIV acquisition and transmission. Contraception comprises critical biomedical prevention for women with or at risk for HIV. Systemic depot progesterone-commonly used throughout Africa-may independently increase risk of HIV acquisition and transmission. Hormonal interventions preventing unintended pregnancy and promoting a protective vaginal microenvironment could synergistically reduce HIV risk especially combined with topical antiretrovirals (ARV). The investigators propose NuvaRing use may contribute to reduction in BV, pregnancy prevention, and decreased rates of HIV shedding in HIV-infected women. Sustained vaginal delivery of contraceptive and ARV PrEP as "multicomponent prevention" is a major focus for scientists but effects on the vaginal environment need careful definition before broad implementation.

Total duration of follow up is no more than 8 months, with 5 months of CVR usage.

Inclusion Criteria:

• BV+ by Amsel Criteria
• Not intending to become pregnant over the course of the study
• If HIV infected, not taking ART
• Capable of providing written informed consent

Exclusion Criteria:

• Current pregnancy
• Desire/intent to become pregnant over the course of the study
• Contraindications to hormonal contraceptive use
• Current cigarette smoking if age is older than 35 years
• Unable to comprehend consent material because of language barrier or psychological difficulty