Inclusion Criteria for women:

• Age 18-50 years old
• Regular menses
• HIV-1 seronegative at screening
• Normal Pap smear at screening or documented normal Pap smear within six months prior to screening
• No evidence of reproductive tract infection (RTI)
• Willing and able to comply with study procedures, including pelvic exams, colposcopy, maintaining a study coital and symptom log, and applying assigned study gel per protocol
• Agree to abstain from sexual intercourse for 24 hours prior to the enrollment visit

• Agree to abstain from the following activities from at least 48 hours prior to enrollment through the Day 14 visit:

  • Insertion of fingers and other objects into the vagina
  • Receiving oral sex
  • Receiving anal sex
  • Using a diaphragm, cervical cap, female condom, or vaginal contraceptive ring
  • Using vaginal products other than the study gels, including douches, lubricants, or feminine hygiene products
• In a monogamous sexually active relationship with one male partner
• Report having vaginal intercourse only with that partner at least two times per week
• No other reported partner in the prior six months and no plan to have another partner for the duration of the study
• Agree to use condoms for each act of vaginal intercourse during participation in the study
• Their male partner is informed and also consents to participate in the study
• Willing to have male partner informed and treated if an STD is diagnosed at screening or during the study

Inclusion Criteria for men:

• Age 18 years or older
• HIV-seronegative and free of other STI at screening exam
• One female sexual partner; no other reported partner in the prior six months and no plan to have another partner for the duration of the study
• Willing and able to comply with study procedures, including clinic visits, interviews and acceptability evaluation, and consistent use of condoms during enrollment in the study
• Willing to have female partner informed and treated if an STD is diagnosed at screening or during the study

Exclusion Criteria for women:

• Pregnancy or desire to become pregnant at time of study participation
• Currently breastfeeding
• Delivery or abortion within last eight weeks

• History of any male sexual partner other than current partner in past six months

  - No abnormal (DAIDS grade 1 or higher) laboratory results at baseline, including hematology, liver and kidney function

• History of post-coital vaginal bleeding in the past three months
• History of surgery to remove uterus or cervix
• History of surgery on the external genitalia, vaginal, or cervix in the past month
• Clinically significant chronic medical condition that is considered progressive, including cardiopulmonary disease, renal disease, hepatic disease, diabetes mellitus.
• History of sensitivity/allergy to latex
• Existence of a clinically detectable genital abnormality at screening (e.g. ulcer, congenital abnormality, any lesion with mucosal disruption)
• Concurrent participation in another trial of a vaginal product
• Have any other condition that in the opinion of the investigator might interfere with the evaluation of the study objectives

Exclusion Criteria for men:

• History of genital surgery in the past month
• Clinical or laboratory evidence of an STI.
• History of sensitivity/allergy to latex
• History of any sexual partner other than their current partner in the past six months