Comparing Immune Response of 2 vs 3 HPV Doses (27-45 Years Old)

Inclusion criteria: 1. Females 27-45 years old. 2. Ability to give informed consent. 3. Has not received any prior doses of the HPV vaccine. This will be verified by the person and state registry (Immtrac), as well as the person's electronic medical record. 4. Reliable telephone access for the duration of the project. 5. Can read and speak in either English or Spanish. 6. Identified source of funding for vaccine such as Medicaid, private health insurance, Texas Healthy Women program, etc. 7. Reports consistent use of reliable birth control and plans to continue its use through study month 13. Exclusion criteria: 1. Currently pregnant or plans to become pregnant or donate eggs in the next 13 months. Any subjects with positive pregnancy tests at the initial visit will be disqualified from the study and advised to seek prenatal care. 2. Has an immunodeficiency or autoimmune disease such as HIV infection, lymphoma, leukemia, lupus, rheumatoid arthritis, inflammatory bowel disease, or other autoimmune condition. 3. Currently receiving treatment or medication that can suppress immune function including radiation therapy, chemotherapy, cyclosporin, leflunomide (Arava), TNF-α antagonists, monoclonal antibody therapies (including rituximab \[Rituxan\]), intravenous gamma globulin (IVIG), antilymphocyte sera, other therapy known to interfere with the immune response, or systemic corticosteroids (by mouth or intramuscular injection). Those using or have used steroids that are inhaled, placed in the eye, applied on the skin, or injected into the joint/soft tissue will be considered eligible for the study. 4. History of splenectomy 5. Known allergies to any vaccine components, including aluminum, yeast or Benzonase. 6. Febrile at ≥100°F in the 24 hours prior to vaccination. The patients may be rescheduled for a later date. 7. History of thrombocytopenia or any coagulation disorder that would contraindicate intramuscular injections. 8. History of \>10 sexual partners in their lifetime at time of enrollment 9. Plans to move out of the Galveston/Houston area in the 13 months following study entry.