Introduction: The aim of this study was to describe trends in the diagnosis and treatment of women referred from the national screening program with cervical intraepithelial neoplasia (CIN) in the Netherlands, and to compare these trends with national guidelines and identify potential areas for improvement for the new primary high-risk HPV screening program. Material and methods: We conducted a population-based cohort study using data from the Dutch pathology archive. Women aged 29-63 years who took part in the Dutch cervical screening program between 1 January 2005 and 31 December 2014 were selected. Three referral groups were identified: direct referrals and those referred after either one (first indirect referrals) or two (second indirect referrals) repeat cytology tests, totaling 85 239 referrals for colposcopy. The most invasive management technique and the most severe diagnosis of each screening episode was identified. Rates of management techniques were calculated separately by referral type, highest CIN diagnosis and age group. Results: In all, 85.1% of CIN 3 lesions were treated with excision (either large excision or hysterectomy) and 26.4% of CIN 1 lesions were treated with large excision. Rates of overtreatment (CIN 1 or less) in see-and-treat management were higher for indirect referrals than for direct referrals and increased with age. Large excision rates increased with CIN diagnosis severity. Conclusions: Despite guideline recommendations not to treat, CIN 1 lesions were treated in just over 25% of cases and approximately 15% of CIN 3 lesions were possibly undertreated. Given the expected increase in CIN detection in the new primary high-risk HPV screening program, reduction in CIN 1 treatment and CIN 2 treatment in younger women is needed to avoid an increase in potential harm.