Hello... I understand your problem, I think you should know that HPV vaccine protects against 70-80% of the cervical cancers produced by papilloma virus... on the other 20-30 % is generally not effective due to limited effect on the strain causing this... So cervical cancer screening still have to be done on regular basis.... the main idea is to vaccinate before the first sexual contact, since HPV virus is sexuallly transmitted so that maximum protection is achieved... It should be avoided if a person is allergic to the vaccine Base or if they are pregnant... General dose schedule is 0( day of vaccination), 2 months and 6 months total 3 doses.. Not only cervical cancer it is also effective in preventing genital warts, anal cancer... Kindly consult a nearest gynecologist for further queries...