The impact of age at initial HPV vaccination on cervical cancer screening participation in a nationally representative cohort of women in the United States

Objective A better understanding of factors associated with cervical cancer screening can inform strategies for cervical cancer prevention. This study examined the relationship between age at human papillomavirus (HPV) vaccination and participation in cervical cancer screening among a nationally representative sample of women in the United States.Methods We utilized data from the National Survey of Family Growth for the years 2015-2019 focusing on women aged 18-24 vaccinated against HPV. Age at first HPV immunization was analyzed as both a dichotomous (vaccinated at 9-12 vs. 13-23 years) and a continuous variable. The outcome measured was ever having a Pap smear. Multivariable logistic regression that accounted for complex survey design was employed to estimate adjusted prevalence ratios and differences from average marginal predictions.Results The study comprised 981 individuals, representing 6.05 million women. Over half of the study population had a Pap test (57.4%). Women vaccinated at ages 9-12 were less likely to participate in screening compared to those vaccinated at ages 13-23 [risk difference: -9.1, 95% confidence interval (CI) -16.7 to -1.5)] which translates into 120,260 fewer women nationwide getting cervical cancer screening. Each 1-year increase in age at first vaccination was associated with a 1.1% (95% CI, -0.1 to 2.4%) higher probability of having a Pap test, but this linear trend was not statistically significant.Conclusions Our study underscores the importance of promoting cervical cancer screening not only among unvaccinated women but also among those who received the HPV vaccine at the recommended ages of 9-12.