Histologic Development of Cervical Ectopy

Abstract
Cervical ectopy has been proposed as a risk factor for chlamydial infection, HIV, and other sexually transmitted diseases (STDs). Ectopy is a histologic phenomenon resulting from a complex interplay of morphologic and hormonal processes. Reproductive hormones influence the production of ectopy during late fetal life, puberty, pregnancy, and with use of oral contraceptives. Ectopy is modified over time by squamous metaplasia and epitheliazation, low pH, trauma, and possibly by cervical infection. The authors review the histologic development of ectopy from late fetal life to menopause to understand STD risk. Ectopy is often assessed and quantified by direct, unaided observation during speculum examinations. This method may result in inaccurate estimates and misclassification with the transformation zone. Valid, reproducible measures of ectopy are necessary for epidemiologic studies to examine the impact of exogenous hormonal contraceptives on the development of ectopy and on potential infection risk.