NHANES data from 2003 to 2006 and 2009 to 2012 were analyzed. Because adolescents were not oversampled after 2006, there was a reduced number of 14- to 19-year-olds in the second time period. Years 2003 to 2006 were considered the prevaccine era because vaccination was first recommended in June 2006. Analyses for the present report were limited to participants aged 14 to 34 years with adequate self-collected cervicovaginal samples. In 2003 to 2006, a total of 3325 females aged 14 to 34 years were interviewed; 3210 (96.5%) received an examination in an MEC. Of those, 2649 (82.5%) submitted a self-collected cervicovaginal swab, and 2587 (80.6%) samples were adequate for DNA typing (as discussed in the Specimen Collection and Laboratory Methods section). In 2009 to 2012, a total of 2473 females aged 14 to 34 years were interviewed; 2403 (97.2%) received an examination in an MEC. Of those, 2070 (86.1%) submitted a cervicovaginal swab, and 2061 (85.8%) were adequate for DNA typing. HPV prevalence testing among males was not included in NHANES during this time period.