Study of How Bacterial Vaginosis and Its Treatment Affects Cervical and Vaginal Tissue

Inclusion Criteria:

- Be of age 18 - 50 years-old, inclusive;

- Have a current BV infection (Nugent score 7 - 10) or intermediate vaginal flora (Nugent score 4 - 6), as diagnosed by Nugent score in the clinic (with later validation of the Nugent score by a blinded separate laboratory);63

- Regular menses with the last 2 menses 21-35 days apart;

- Willing and able to comply with study procedures, including the use of oral treatment for BV.

Exclusion Criteria:

- Contraindications to the use of oral metronidazole including:

- Daily alcohol consumption and be unable or unwilling to abstain from alcohol while taking metronidazole tablets;

- Known hypersensitivity to oral metronidazole;

- Chronic immune suppression (including, but not limited to chronic steroid use, chronic anti-fungal use, Diabetes Mellitus, organ transplant);

- An abnormal Pap smear documented in the past 12 months defined as:

- ASC-US without a normal repeat Pap smear at least 6 months later;

- ASC-US with positive reflex high-risk HPV testing (ASC-US/HPV+), low grade squamous epithelial lesion or high grade squamous intraepithelial lesion, ASC-H, atypical glandular cells, or malignant cells;

- It has been less than 3 months since the patient's last Depo medroxyprogesterone acetate (DMPA) injection and she has not had 2 normal, spontaneous menses since last using DMPA;

- Use of any other hormonal contraceptive method within past 2 months (oral, transdermal, transvaginal, implant, or hormonal intrauterine device);

- Use of oral or vaginal antibiotics or anti-fungals in the last 14 days;

- Surgery or biopsy of the vulva, vagina, or cervix within the past 30 days;

- History of hysterectomy;

- Pregnancy within the past 3 months;

- Current breastfeeding;

- HIV-1 sero-positivity in the participant (by history or buccal HIV-1 swab) or her current sexual partner(s);

- Current use of anti-viral suppression medications for Herpes Simplex Virus (HSV) (a history of HSV without active lesions is permitted);

- Current active sexually transmitted infection (STI);

- Presence of vaginal semen in the last 48 hours, per patient's report or as detected by prostate specific antigen (PSA) test;

- Use of douches, vaginal products or anything in the vagina in the past 48 hours;

- Current presence of vulvar, anal and or vaginal genital warts;

- Current tobacco use (any amount)

- Other conditions that, in the opinion of the investigator, would constitute contraindications to participation in the study or would compromise ability to comply with the study protocol, such as any major chronic illness including cancer, serious autoimmune disease or a major psychiatric disorder not under good control; and

- Current participation in any other drug or device study, or any study which, in the opinion of the investigator, would jeopardize interpretation of results of this study.