Interactions Between Antiretrovirals (ARVs) and Combined Oral Contraceptives (COCs)

Inclusion criteria

• Willing to provide informed consent
• Willing to take COCs and follow all study requirements
• Has regular menstrual cycles every 21-35 days (when not taking hormonal contraception)
• Last menstrual period (LMP) <35 days before study entry
• Has body mass index of 18-30
• Negative urine pregnancy test as enrollment
• Documented HIV-1 infection
• On nevirapine-containing ART for at least three months (ART group only)
• CD4 cell count of greater than or equal to 350 (for non-ARV group only)
• Currently sexually active and plans to stay sexually active for the next 6 months

Exclusion criteria

• Medical contraindications to COC use
• Recent pregnancy (within 3 months)
• Has breastfed in last 3 months
• Last pregnancy was ectpoic
• Has been sterilized
• Has had any of the following conditions since last pregnancy, or since menarche if never pregnant:

Pelvic Inflammatory disease Diagnosis of infertility

• Has had DMPA within 6 months or NET injectable within 3 months of study entry (or has had no menses since last injection regardless of its timing)
• has taken other hormonal therapies besides COCs (e.g., combined injectables, progestin implants or intrauterine systems, progestin-only contraceptive pills, medroxyprogesterone acetate, hormone replacement therapy) within 30 days of study entry
• Has an acute infection or other opportunistic diseases requiring therapy within 14 days before enrollment
• Has active drug or alcohol use that, in the opinion of the investigator, would interfere with adherence to study requirements
• Has taken any prohibited medication within 30 days before study entry
• Has chronic diarrhea, malabsorption or inability to maintain an adequate oral intake
• Has any condition (social or medical) which in the opinion of the investigator would make study participation unsafe or complicate data interpretation