- The third dose will be administered at the time when maximum protection is required, near the onset of sexual activity Thus the National Institute of Public Health was commissioned to monitor anti-HPV antibody levels in women who received the anti-HPV vaccine to determine non-inferiority of the extended scheme in 9-year-old girls compared with the traditional scheme of 3 doses in women 18 to 24 years of age. To this end, a sentinel cohort will be formed to evaluate immunogenicity levels in 3 age groups, and stratified by vaccine type. The hypothesis is that in 9-year-old girls who are administered the amplified HPV vaccination scheme (0-6-60) show immunogenicity levels that are not lower than those of adult women who have been administered the traditional scheme (0-1/2-6).