Human papillomavirus vaccination and cervical cytology in young minority women.

Background: Continued surveillance of human papillomavirus (HPV) vaccination is necessary to identify clinical benefits, particularly given the low rate of vaccine uptake and completion and vaccination of many young women after sexual debut. We studied the effect of catch-up HPV vaccination on cervical cytology and HPV infection in sexually active, low-income and minority young women.

Methods: We conducted a cross-sectional study of 235 women aged 21 to 30 years undergoing routine cervical cytology testing. Demographic and behavioral characteristics were self-reported. HPV vaccination status was determined by self-report and verified with electronic medical records. Liquid-based cytology samples were tested for HPV genotypes. Adjusted prevalence ratios between HPV vaccination and (1) abnormal cervical cytology result and (2) HPV genotype were estimated.

Findings: At the time of the study, 96 women (41%) had received at least 1 HPV vaccination, 54 of whom had completed the series; 97% of women were vaccinated after sexual debut. Twenty-four (10%) women had an abnormal cervical cytology result. The prevalence of abnormal cytology was 65% lower in women who received at least 1 HPV vaccination versus unvaccinated women (adjusted prevalence ratio, 0.35; 95% confidence interval, 0.14-0.89). Among 232 women with genotype results, 46 (20%; 95% confidence interval, 15%-26%) had HPV infection detected. HPV types 16, 18, 45, 53, and 66 were most prevalent.

Conclusions: The prevalence of abnormal cytology was lower in vaccinated versus unvaccinated women, despite receipt of vaccination after sexual debut. Continued assessment of HPV vaccine effectiveness before and after sexual debut on HPV infection and cervical dysplasia is needed.