Altogether 14.000 1995-1997 born women resident in communities where herd effect against high-risk HPV infections was created with gender-neutral vaccination of birth cohorts 1992-1995 (A-communities) or not (control C-communities) in 2007-2010 with the bi-valent HPV16/18 vaccine will be invited to participate a randomized screening trial at the ages of 25 and 28 years.~Cervical samples will be analysed for HPV DNA with MGP (Modified General Primer) primer system followed by MALDITOF(matrix assisted laser desorption ionization-time of flight mass spectrometry) mass spectrometry on the SEQUENOM (translation of genomic science into solutions for molecular medicine and biomedical research) platform (HPV).~With assumed 65% and 90% participation and retain rates the trial has 80% power to show non-inferiority of the infrequent vs. the frequent screening information.~At the study-end testing the null hypotheses of no difference in the incidence of the CIN2/3 (cervical squamous intraepithelial neoplasia 2/3) end-points comparing the A1 vs. C and A2 vs. C intervention arms will be done using the Mantel-Haenszel one degree of freedom chi-square statistics.~Work Content Letters of invitation to visit cervical screening at the nearest FICAN (Comprehensive Cancer Center Finland)-Mid study site will be send to the approximately 14.000 unvaccinated women at the ages of 25 and 28 years Following informed consent cervical liquid-based cytology samples will be taken for HPV DNA and/or cytology screening at study visits.~All cytological screening results will be communicated to Arm A1 and Arm C study participants. Arm A2 participants will get the test results at the age of 28. However, results of the cytology testing indicative of colposcopy according to local standard of care and currently accepted EU (the European Union) -guidelines (Käypä Hoito 2010, Franceschi et al. 2011) will be immediately communicated to all study participants. HPV DNA results will be communicated to all study participants at the study end. Pertinent colposcopy referrals to organized health care will be made.~All study participants will be offered a possibility to give an oropharyngeal sputum sample after 30 seconds gargling of sterile physiological saline (5 ml) for HPV PCR (polymerase chain reaction) analysis.
To identify: 1) Whether being informed infrequently results about screening is at least as a) safe and b) accurate as frequently obtaining all information from (the present combination of opportunistic/organized) cervical screening by comparing regimen results of two screening visits at the ages of 25 and 28 years (Arm A1) vs. results of one screening visit at the age of 28 years (Arm A2) in unvaccinated herd effect protected women. Unvaccinated, frequently screened women, who are not under herd effect protection will be controls (C).