Risk factors for cervical intraepithelial neoplasia in Taiwan.

A population-based case-control study was conducted in Taiwan between July 1991 and June 1994 to evaluate the significance between risk factors for cervical intraepithelial neoplasia (CIN) among Taiwanese women. Personal interviews were compiled with 288 histologically confirmed CIN who were matched by age to 576 randomly selected controls with normal cervical smears. Using logistic regression models to simultaneously evaluate the effects of multiple factors as predictors of CIN, we found that the strongest risk was associate with HPV infection (OR = 5.02). Other significant risks included husband's visiting prostitutes (OR = 2.56), four or more vaginal deliveries (OR = 2.01), two or more induced abortions (OR = 1.96), and multiple sex partners (OR = 1.87). A protective effect was also noted with the use of condoms (OR = 0.38). These data support the hypothesis that CIN is sexually transmitted in Taiwan's population and may have a viral etiology. Furthermore the results indicate the important role of the husband's visiting prostitutes and the nonuse of condoms as contributing factors in the high incidence rate for CIN in a population.