Regression rate of high-grade cervical intraepithelial lesions in women younger than 25 years

The incidence and clinical course of high-grade cervical intraepithelial lesions (CIN 2/3) are age dependent. In CIN 3, the recommended treatment is conization, which increases the risk of cervical insufficiency or premature deliveries. But data concerning spontaneous regression of CIN 3 are rare.

Between 2007 and 2017, we identified 156 women under the age of 25 with CIN 2 (23%) or CIN 3 (77%), who had a consultation and were treated at the Colposcopy Unit, Hospital of Düsseldorf, Germany. This is a retrospective cohort study. These patients had colposcopical follow-ups every 4-6 months. Moreover, we analyzed various parameters to predict regression of cervical lesions in this age group.

Patients diagnosed with CIN 2 showed regression in 88% (n = 30) and women with CIN 3 had a regression rate of 29% (n = 34). Complete regression was observed in 86.7% of CIN 2 and 47.1% of CIN3. Mean time to regression was 21 M (months) [2-70 M]. 70.9% of the patients were treated by surgery (LEEP) after persistence or progression. We identified several predictors for regression of CIN 2/3 in young women: the regression rate of CIN2 is significantly higher than CIN 3 (p < 0.001). Clearance of HPV infections had significantly higher rates of regression compared to persisting HPV infections (p < 0.001). HPV-vaccinated women showed significantly higher regression rates (p = 0.009).

These data show that an expectative close follow-up in women with CIN 3 younger than 25 is possible with regression rates of 29% also for CIN 3. Especially in women who were HPV vaccinated and those who cleared their HPV infection. A frequent colposcopical follow-up every 3-4 months is important for CIN 3 and every 6 months for CIN 2.