{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T09:47:32Z","timestamp":1782294452047,"version":"3.54.5"},"reference-count":35,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,6,22]],"date-time":"2026-06-22T00:00:00Z","timestamp":1782086400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Cervical intraepithelial neoplasia grade 1 (CIN1) is usually managed conservatively, but uncertainty remains about the subsequent risk of clinically significant high-grade disease, particularly after repeated CIN1. We conducted a retrospective population-based cohort study using anonymized cervical cytology, HPV, and histopathology records from Northern Norway from 2011 to 2025. We described temporal trends in screening-related outcomes and estimated the 5-year risk of CIN3+ after histologically confirmed CIN1 diagnosed in a single calendar year or in two consecutive calendar years. Across 2011\u20132025, the annual datasets comprised 334,471 screening records; 35,796 had ASC-US+ cytology (10.7%), 29,723 had a positive HPV test (8.9%), 35,416 underwent biopsy (10.6%), and 7870 were diagnosed with CIN2+ (2.4%). HPV positivity increased from 0.9% in 2011 to 15.7% in 2025, whereas CIN2+ detection peaked at 3.1% in 2018 and declined to 1.8% in 2025. In person-based analyses, the 5-year risks after CIN1 diagnosed in a single calendar year versus two consecutive calendar years were 4.3% versus 3.4% for CIN3+, 0.2% versus 0.1% for cervical cancer, and 15.4% versus 14.3% for CIN2+. Repeated CIN1 was not associated with higher subsequent CIN3+ risk, supporting conservative, risk-based follow-up after CIN1 biopsy.<\/jats:p>","DOI":"10.3390\/pathogens15060657","type":"journal-article","created":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T07:57:24Z","timestamp":1782287844000},"page":"657","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Five-Year Risk of CIN3+ After CIN1 Biopsy in a Norwegian Screening Setting: Comparison of CIN1 Diagnosed in a Single Calendar Year and in Two Consecutive Calendar Years"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8250-3992","authenticated-orcid":false,"given":"Sveinung Wergeland","family":"S\u00f8rbye","sequence":"first","affiliation":[{"name":"Department of Clinical Pathology, University Hospital of North Norway, 9006 Tromso, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mona","family":"Antonsen","sequence":"additional","affiliation":[{"name":"Department of Clinical Pathology, University Hospital of North Norway, 9006 Tromso, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-3559-7153","authenticated-orcid":false,"given":"Elin","family":"Richardsen","sequence":"additional","affiliation":[{"name":"Department of Clinical Pathology, University Hospital of North Norway, 9006 Tromso, Norway"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,22]]},"reference":[{"key":"ref_1","first-page":"229","article-title":"Global cancer statistics 2022: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries","volume":"74","author":"Bray","year":"2024","journal-title":"CA Cancer J. 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