title: Natural history of established low grade cervical intraepithelial (CIN 1) lesions.
abstract: THE AIM of the present study was to ascertain the natural history of cervical intraepithelial lesions 1 (CIN 1) and to develop recommendations to optimize follow-up.
  
  
  METHODS
  Patients referred for colposcopy from January, 1996 to July, 2005 were reviewed. A prospectively maintained database was quarried for demographic, clinical, and pathologic data.
  
  
  RESULTS
  The cohort included 1,001 patients with CIN 1. At 6 months, 330 patients (49%) regressed to normal, 305 (45%) had persistent low grade, while 45 (7%) progressed to high grade lesions. At 12 months, of those with negative pathology at 6 months, 200 (80%) remained negative, 42 (16%) demonstrated low grade and 9 (4%) progressed to high grade lesions. Of those with low grade lesions at 6 months, 131 (50%) regressed, 121 (46%) had persistent low grade, and 10 (4%) progressed to high grade lesions.
  
  
  CONCLUSIONS
  Our data demonstrates a low rate of progression for CIN 1, suggesting it may be reasonable to prolong the screening interval in women with CIN 1.
authors.affiliation: Columbia University College of Physicians and Surgeons, Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, New York, NY 10032, USA. nishabansal1@yahoo.com
authors.forename: Nisha
authors.initials: N
authors.lastname: Bansal
authors.forename: Jason D
authors.initials: JD
authors.lastname: Wright
authors.forename: Carmel J
authors.initials: CJ
authors.lastname: Cohen
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Herzog
mesh_terms: D000328:Adult; D001706:Biopsy; D015331:Cohort Studies; D003127:Colposcopy; D018450:Disease Progression; D005260:Female; D006801:Humans; D002583:Uterine Cervical Neoplasms / Q000473:pathology*; D002578:Uterine Cervical Dysplasia / Q000473:pathology*