OBJECTIVE To evaluate the serial changes in colposcopic and cervicographic findings of women with cervical intraepithelial neoplasia (CIN) II and III enrolled in a phase III randomized comparison of oral beta carotene and placebo. METHODS All subjects treated with beta carotene or placebo for at least 6 months were included if they met the criteria of persistent or progressive disease (no change or worsening of CIN grade) or disease regression (improvement of two grades or more). These two groups were compared for changes in colposcopic and cervicographic patterns. Colposcopically directed biopsies and cervicography were done at enrollment and after 6 months. Quarterly Papanicolaou smears and colposcopic assessments also were performed. Findings of mosaic pattern, punctation, and white epithelium were graded and diagrammed at colposcopic examinations. Cervicographic measurements of the centripetal movement of metaplastic epithelium were recorded. Data were analyzed by chi 2 analysis and Fisher exact tests. RESULTS Data were available for 23 subjects with regression and 16 with persistent lesions. Small lesions were significantly more likely to regress than large ones. Lesions without coarse punctation were significantly more likely to regress than lesions with coarse punctation, and lesions with mild acetowhite changes were more likely to regress than those with dense white epithelium. A pattern of centripetal movement of the metaplastic epithelium toward the cervical os was noted in lesions that regressed, but not in those that persisted or progressed. CONCLUSIONS This study describes the centripetal growth of metaplastic squamous epithelium associated with the regression of CIN II and III. This observation contributes to our understanding of the process of disease regression in CIN and may be useful in identifying individuals for conservative management. Failure to identify this pattern correlates with persistent or progressive disease.