• human papillomavirus;
  • atypical squamous cells of undetermined significance;
  • low-grade squamous intraepithelial lesions;
  • multilevel models


We investigated short-term persistence of human papillomavirus (HPV) infection among 2,408 women with low-grade or equivocal cytological abnormalities followed for 24 months. Odds ratios (ORs) for persistence to the next 6-month visit were estimated by a discrete time survival model. Prevalent HPV infections persisted longer in older women, but no association with age was found for incident HPV infections. Increased likelihood of persistence was found among current smokers of >20 cigarettes per day compared with smokers of ≤10 cigarettes per day (OR=1.43; 95% confidence interval [CI]: 1.02–2.01) and among current injectable contraceptive users (OR=1.15; 95% CI: 1.01–1.32). Persistence was more likely among infections with higher viral load (OR=2.05; 95% CI: 1.65–2.53) or with concurrent cytological abnormalities (OR=1.19; 95% CI: 1.03–1.39 and 1.29; 95% CI: 0.99–1.70 for ASCUS/LSIL and ASC-H/HSIL, respectively). We conclude that new HPV infections in older women are not riskier by the metric of viral persistence than those in younger women. Other risk factors such as oral contraceptive use and multiparity that have been associated with cervical cancer or cervical intraepithelial neoplasia grade 3 were not associated with short-term HPV persistence.