Cervical Ectopy and the Acquisition of Human Papillomavirus in Adolescents and Young Women

Abstract

Higher rates of human papillomavirus (HPV) in adolescents and younger women have been attributed to their greater extent of "cervical ectopy," defined as columnar and metaplastic epithelia on the ectocervix. Our objective was to estimate associations between ectopy and incident HPV in healthy adolescents and young women. Enrolled between October 2000 and October 2002, this prospective cohort included women aged 13-21 years who were sexually active, without previous cervical intraepithelial neoplasia, cervical procedures, or immunosuppression, with menarche within 6 years before enrollment, and negative for HPV DNA at baseline. Every 4 months, extent of ectopy was quantitatively measured using colpophotography and computerized planimetry. Cox proportional hazards models examined associations between ectopy and incident HPV, defined as the first positive HPV result during follow-up. The 138 women attended 509 total visits. At baseline, mean age was 16.7 years and mean extent of ectopy was 25% of the total cervical face. Incident HPV of any type was detected in 42 (30%) women and was not significantly associated with baseline ectopy (hazard ratio 1.09, 95% confidence interval 0.96-1.25; P=.20; ectopy in units of 10%), or with ectopy measured 4 months before HPV detection (hazard ratio 1.09, confidence interval 0.94-1.26; P=.25). Our sample size had 80% power to detect a hazard ratio of 1.9 (with two-tailed α=0.05). Results were similarly insignificant for HPV subgroupings of incident high-risk, low-risk, α9, and α3/α15 types, and when adjusted for new sexual partners. Extent of cervical ectopy was not associated with HPV acquisition in healthy adolescents and young women. Biological vulnerabilities may lie in immune function or other characteristics of the cervical epithelium. II.