The authors were interested in the changes in rates of cervical intraepithelial neoplasia grades 2, 3 and adenocarcinoma in situ (CIN2+) following the introduction of the human papillomavirus (HPV) vaccine and changes to cervical cancer screening recommendations. They conducted population-based laboratory surveillance for CIN2+ in in five states of the US between 2008-2015. A total of 16,572 CIN2+ cases were reported during that time. Among women aged 18-20 and 21-24 years, CIN2+ rates declined in all sites examined, while in women aged 25-29, 30-34 and 35-39 years, the trends in rates were different across sites. The authors found that the percentage of women screened annually declined in all sites and age groups. Compared with 2008-2009, rates among screened women were significantly lower for all three time periods examined in women aged 18-20 years: 2010-2011 incidence rate ratio [IRR] 0.82 (95%CI 0.67-0.99), 2012-2013 IRR 0.63 (95%CI 0.47-0.85), and 2014-2015 IRR 0.44 (95%CI 0.28-0.68). For women aged 21-24 years the rates were significantly lower for the latter two time periods only: 2012-2013 IRR 0.86 (95%CI 0.79-0.94), and 2014-2015 0.61 (95%CI 0.55-0.67). However, rates among screened women increased for age groups 25-29, 30-34 and 35-39 years. Therefore from 2008-2015, both CIN2+ rates and cervical cancer screening declined in women aged 18-24 years.
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