Objective: Cervical intraepithelial neoplasia grades 2-3 (CIN2-3) are usually treated by cone excision, although only 30% progress to cancer and 6-50% regress spontaneously. The aim of this study was to examine the influence of clinical factors like smoking habits, number of lifetime sexual partners, age at first sexual intercourse, sexual activity span and hormonal versus non-hormonal contraception type on the regression rate of CIN2-3.
Methods: In this prospective population-based cohort study 170 women aged 25-40 with abnormal cytology and colposcopy-directed biopsies showing first time onset CIN2-3 were consecutively included. The interval between biopsy and cone excision was standardized to minimum 12 weeks. Regression was defined as ≤ CIN1 in the cone biopsy.
Results: The regression rate was 22%. Consistent condom use, defined as those women whose partners used condoms for all instances of sexual intercourse, was infrequent (n=20, 12%). In univariate analysis consistent condom use, hormonal contraception and age at first sexual intercourse significantly predicted regression. In a multivariate analysis only consistent condom use remained as an independent predictor of regression (regression rate 55%, p=0.001, hazard ratio=4.4).
Conclusion: Consistent condom use between punch biopsy and cone excision in first-time onset CIN2-3 patients significantly increases the regression rate.